feat(http-client): request bodies from DTOs in other modules, header completion

Generating a request from a Spring mapping looked for the @RequestBody
type only beside the controller or in the same source root, so a DTO in
another Maven module came out as {}. Types not found there are now looked
up in the project index, in the imported (or same / wildcard-imported)
package, and the fields of their superclasses are included.

Header names complete on the lines after a request line, and values of
the common headers (Content-Type, Accept, Authorization, …) after the
colon. Requests opened from an endpoint use its module's server address
instead of a fixed localhost:8080.

.github/workflows/nightly.yml

@@ -47,7 +47,7 @@ jobs:
             exit 0
           fi
           # No `nightly` tag yet (the first run): compare fails and the build goes on.
-          status="$(gh api "repos/$GH_REPO/compare/nightly...$sha" --jq .status 2>/dev/null || echo ahead)"
+          status="$(gh api "repos/$GH_REPO/compare/nightly...$sha" --jq .status 2>/dev/null)" || status=ahead
           if [ "$status" != ahead ] && [ "$FORCE" != true ]; then
             echo "::notice::$sha is not newer than the last nightly"
             exit 0

.github/workflows/release-build.yml

@@ -151,6 +151,13 @@ jobs:
           $hash = (Get-FileHash $asset -Algorithm SHA256).Hash.ToLower()
           "$hash  $asset" | Out-File -Encoding ascii "$asset.sha256"
           gh release upload $env:TAG $asset "$asset.sha256" --clobber
+          if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+          if ($env:TAURI_SIGNING_PRIVATE_KEY) {
+            pnpm exec tauri signer sign --app-version $version $asset
+            if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+            gh release upload $env:TAG "$asset.sig" --clobber
+            if ($LASTEXITCODE -ne 0) { exit $LASTEXITCODE }
+          }
 
   # The remote development server, per host platform it can run on. The desktop
   # app downloads the one for the host (ide-tools `server`) and installs it over SSH.
@@ -233,6 +240,8 @@ jobs:
               [/_x64\.app\.tar\.gz$/, ["darwin-x86_64", "darwin-x86_64-app"]],
               ...windows("aarch64", /_arm64_en-US\.msi$/, /_arm64-setup\.exe$/),
               ...windows("x86_64", /_x64_en-US\.msi$/, /_x64-setup\.exe$/),
+              [/_windows_arm64_portable\.zip$/, ["windows-aarch64-portable"]],
+              [/_windows_x64_portable\.zip$/, ["windows-x86_64-portable"]],
             ];
             const platforms = {};
             for (const sig of sigs) {

Cargo.lock

@@ -8727,7 +8727,7 @@ checksum = "3a0219bd7d979d58245a4f41f695e1ac9f8befdffadd7f61f1bae9e39abc6620"
 [[package]]
 name = "sqlx"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "sqlx-core",
  "sqlx-macros",
@@ -8739,7 +8739,7 @@ dependencies = [
 [[package]]
 name = "sqlx-core"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "base64 0.22.1",
  "bytes",
@@ -8774,7 +8774,7 @@ dependencies = [
 [[package]]
 name = "sqlx-macros"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -8786,7 +8786,7 @@ dependencies = [
 [[package]]
 name = "sqlx-macros-core"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "cfg-if",
  "dotenvy",
@@ -8810,7 +8810,7 @@ dependencies = [
 [[package]]
 name = "sqlx-mysql"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "bitflags 2.13.2",
  "byteorder",
@@ -8835,7 +8835,7 @@ dependencies = [
 [[package]]
 name = "sqlx-postgres"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "atoi",
  "base64 0.22.1",
@@ -8869,7 +8869,7 @@ dependencies = [
 [[package]]
 name = "sqlx-sqlite"
 version = "0.9.0"
-source = "git+https://github.com/transact-rs/sqlx?rev=10462fa4414c6c7f1ed1d39bb31678e3b726878c#10462fa4414c6c7f1ed1d39bb31678e3b726878c"
+source = "git+https://github.com/l0ng-ai/sqlx?rev=9894985a1babc7e6bc0437da4fd43e3143184073#9894985a1babc7e6bc0437da4fd43e3143184073"
 dependencies = [
  "atoi",
  "flume",

Cargo.toml

@@ -111,7 +111,7 @@ reqwest = { version = "0.13", default-features = false, features = ["rustls-no-p
 rustls = { version = "0.23", default-features = false, features = ["ring", "std", "tls12", "logging"] }
 rustls-platform-verifier = "0.7"
 # Until SQLx releases its libsqlite3-sys 0.39 update (RUSTSEC-2026-0459).
-sqlx = { version = "0.9", git = "https://github.com/transact-rs/sqlx", rev = "10462fa4414c6c7f1ed1d39bb31678e3b726878c", default-features = false, features = ["runtime-tokio", "tls-rustls-ring-webpki", "sqlite", "postgres", "mysql"] }
+sqlx = { version = "0.9", git = "https://github.com/l0ng-ai/sqlx", rev = "9894985a1babc7e6bc0437da4fd43e3143184073", default-features = false, features = ["runtime-tokio", "tls-rustls-ring-webpki", "sqlite", "postgres", "mysql"] }
 tiberius = { version = "0.13", default-features = false, features = ["tds73", "rustls", "sql-browser-tokio"] }
 # Pure-Rust thin Oracle driver; pinned to the beta until it stabilizes.
 oracledb = "=26.0.0-beta.5"

crates/ide-agent/src/acp/e2e.rs

@@ -107,6 +107,7 @@ fn manager(dir: &Path, agent: Arc<FakeV2Agent>) -> AgentManager {
             models_file: dir.join("models.json"),
             custom_agents_dir: None,
             home_dir: None,
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
         connector,

crates/ide-agent/src/acp/tests.rs

@@ -154,6 +154,7 @@ async fn discovery_reads_effort_and_fast_from_session_new_then_stops_the_agent()
             models_file: tmp.path().join("models.json"),
             custom_agents_dir: None,
             home_dir: None,
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
         connector,

crates/ide-agent/src/config.rs

@@ -42,9 +42,38 @@ pub(crate) fn bypass_approvals(config: &[AgentConfigOption]) -> bool {
     let selected = |category: &str| {
         config.iter().find(|o| o.category.as_deref() == Some(category)).and_then(|o| o.current.as_deref())
     };
-    selected("mode").is_some_and(is_bypass_mode)
-        || selected("permissions").is_some_and(|v| matches!(v.to_ascii_lowercase().as_str(), "on" | "true"))
-        || selected("approval").is_some_and(|v| v.eq_ignore_ascii_case("bypass"))
+    ["mode", "permissions", "approval"]
+        .into_iter()
+        .any(|category| selected(category).zip(bypass_value(category)).is_some_and(|(value, bypass)| bypass(value)))
+}
+
+/// For an option of `category` that can approve everything, what tells its approving values.
+fn bypass_value(category: &str) -> Option<fn(&str) -> bool> {
+    match category {
+        "mode" => Some(is_bypass_mode),
+        "permissions" => Some(|v| matches!(v.to_ascii_lowercase().as_str(), "on" | "true")),
+        "approval" => Some(|v| v.eq_ignore_ascii_case("bypass")),
+        _ => None,
+    }
+}
+
+/// Moves options that approve everything without asking to a value that asks: the agent's
+/// default or ask mode, else its first one that asks.
+pub(crate) fn ask_for_approvals(config: &mut [AgentConfigOption]) {
+    for option in config {
+        let Some(bypass) = option.category.as_deref().and_then(bypass_value) else { continue };
+        if option.current.as_deref().is_some_and(|c| !bypass(c)) {
+            continue;
+        }
+        let asks = |v: &&AgentConfigValue| !bypass(&v.value);
+        let value = ["default", "ask"]
+            .iter()
+            .find_map(|preferred| option.values.iter().filter(asks).find(|v| v.value == *preferred))
+            .or_else(|| option.values.iter().find(asks));
+        if let Some(value) = value {
+            option.current = Some(value.value.clone());
+        }
+    }
 }
 
 /// The mode that approves everything without asking (`bypassPermissions`, `yolo`, `full-access`…), if the agent has one.
@@ -341,6 +370,36 @@ mod tests {
         assert!(bypass_approvals(&url_mode));
     }
 
+    #[test]
+    fn asking_for_approvals_keeps_a_mode_that_asks_and_leaves_one_that_does_not() {
+        let mode = |current: &str, values: &[&str]| {
+            options_of(&json!({"modes": {"currentModeId": current,
+                "availableModes": values.iter().map(|v| json!({"id": v})).collect::<Vec<_>>()}}))
+        };
+        let codex = ["read-only", "ask", "auto", "full-access"];
+        for (current, expected) in [("auto", "auto"), ("read-only", "read-only"), ("full-access", "ask")] {
+            let mut c = mode(current, &codex);
+            ask_for_approvals(&mut c);
+            assert_eq!(c[0].current.as_deref(), Some(expected), "{current}");
+            assert!(!bypass_approvals(&c));
+        }
+        let mut claude = mode("bypassPermissions", &["acceptEdits", "default", "plan", "bypassPermissions"]);
+        ask_for_approvals(&mut claude);
+        assert_eq!(claude[0].current.as_deref(), Some("default"));
+        let mut other = mode("yolo", &["yolo", "code", "architect"]);
+        ask_for_approvals(&mut other);
+        assert_eq!(other[0].current.as_deref(), Some("code"));
+
+        let mut c = options_of(&json!({"configOptions": [
+            {"id": "allow_all", "category": "permissions", "type": "select", "currentValue": "on",
+             "options": [{"value": "on"}, {"value": "off"}]},
+            {"id": "approval", "category": "approval", "type": "select", "currentValue": "bypass",
+             "options": [{"value": "bypass"}, {"value": "ask"}]}
+        ]}));
+        ask_for_approvals(&mut c);
+        assert_eq!(ids(&c), [("allow_all", Some("off")), ("approval", Some("ask"))]);
+    }
+
     #[test]
     fn effort_and_fast_categories_are_inferred_from_ids() {
         let c = options_of(&json!({

crates/ide-agent/src/lib.rs

@@ -43,6 +43,9 @@ pub type AgentSink = Arc<dyn Fn(AgentEvent) + Send + Sync>;
 /// Returns the active command execution security policy for the project.
 pub type SecurityHook = Arc<dyn Fn() -> ide_core::settings::AgentSecuritySettings + Send + Sync>;
 
+/// Returns the user's choice of the approvals new tasks start with.
+pub type NewTaskApprovalsHook = Arc<dyn Fn() -> ide_core::settings::NewTaskApprovals + Send + Sync>;
+
 /// Entry changes are batched for this long before they are sent.
 const FLUSH_DELAY: Duration = Duration::from_millis(40);
 /// Updates that arrive this late after `session/load` returns are still replayed history.
@@ -89,6 +92,18 @@ pub struct AgentPaths {
     pub custom_agents_dir: Option<PathBuf>,
     /// The user's home: its `.claude` holds their own skills and commands.
     pub home_dir: Option<PathBuf>,
+    /// Where the values of the agent files' environment variables are kept; without it they stay in the files.
+    pub env_secrets: Option<Arc<dyn EnvSecrets>>,
+}
+
+/// Keeps the values of agent files' environment variables (`agent/<id>/env/<name>`) out of
+/// the files, which keep only the names; the app keeps them in the OS credential store.
+pub trait EnvSecrets: Send + Sync {
+    fn get(&self, key: &str) -> Option<String>;
+    fn set(&self, key: &str, value: &str) -> IdeResult<()>;
+    fn delete(&self, key: &str);
+    /// The keys that start with `prefix`.
+    fn keys(&self, prefix: &str) -> Vec<String>;
 }
 
 /// Starts the ACP server of a provider in a directory, speaking to `client`.
@@ -107,6 +122,7 @@ struct Shared {
     connector: Connector,
     sink: RwLock<Option<AgentSink>>,
     security: RwLock<Option<SecurityHook>>,
+    new_task_approvals: RwLock<Option<NewTaskApprovalsHook>>,
     known: Mutex<HashMap<String, Known>>,
     providers: RwLock<Vec<provider::ProviderSpec>>,
     /// Last probe of each provider.
@@ -136,6 +152,10 @@ impl Shared {
         self.providers.read().iter().find(|p| p.id == id).cloned()
     }
 
+    fn env_secrets(&self) -> Option<&dyn EnvSecrets> {
+        self.paths.env_secrets.as_deref()
+    }
+
     fn emit(&self, event: AgentEvent) {
         let sink = self.sink.read().clone();
         if let Some(sink) = sink {
@@ -155,6 +175,11 @@ impl Shared {
         // Model-specific options are offered separately, never as provider-wide defaults.
         config.retain(|o| o.category.as_deref() != Some("thought_level"));
         config::add_client_options(provider, &mut config);
+        let hook = self.new_task_approvals.read().clone();
+        if hook.is_some_and(|ask| ask() == ide_core::settings::NewTaskApprovals::Ask) {
+            config::ask_for_approvals(&mut config);
+            return config;
+        }
         if let Some((o, v)) = config::bypass_mode(&config).map(|(o, v)| (o.id.clone(), v.value.clone()))
             && let Some(o) = config.iter_mut().find(|c| c.id == o)
         {
@@ -446,13 +471,14 @@ impl AgentManager {
     fn with_connector(paths: AgentPaths, runtime: tokio::runtime::Handle, connector: Connector) -> Self {
         let known =
             std::fs::read(&paths.models_file).ok().and_then(|b| serde_json::from_slice(&b).ok()).unwrap_or_default();
-        let providers = RwLock::new(provider::load(paths.custom_agents_dir.as_deref()));
+        let providers = RwLock::new(provider::load(paths.custom_agents_dir.as_deref(), paths.env_secrets.as_deref()));
         let shared = Arc::new(Shared {
             paths,
             runtime,
             connector,
             sink: RwLock::new(None),
             security: RwLock::new(None),
+            new_task_approvals: RwLock::new(None),
             known: Mutex::new(known),
             providers,
             probes: Mutex::new(HashMap::new()),
@@ -501,9 +527,14 @@ impl AgentManager {
         *self.shared.security.write() = Some(hook);
     }
 
+    /// Sets the callback that reads which approvals new tasks start with.
+    pub fn set_new_task_approvals_hook(&self, hook: NewTaskApprovalsHook) {
+        *self.shared.new_task_approvals.write() = Some(hook);
+    }
+
     /// The agents (custom ones re-read), whether each is installed, and what they offered last time.
     pub fn providers(&self) -> Vec<AgentProvider> {
-        let specs = provider::load(self.shared.paths.custom_agents_dir.as_deref());
+        let specs = provider::load(self.shared.paths.custom_agents_dir.as_deref(), self.shared.env_secrets());
         let in_use: std::collections::HashSet<String> =
             self.tasks.read().values().map(|t| t.state.lock().task.provider.clone()).collect();
         let list = specs
@@ -537,7 +568,7 @@ impl AgentManager {
         let Some(dir) = self.shared.paths.custom_agents_dir.clone() else {
             return Err(IdeError::unavailable("there is no custom agents directory"));
         };
-        provider::set_builtin_command(&dir, id, command.as_deref())
+        provider::set_builtin_command(&dir, self.shared.env_secrets(), id, command.as_deref())
     }
 
     /// Sets the environment variables built-in `id` starts with; empty clears them.
@@ -545,7 +576,7 @@ impl AgentManager {
         let Some(dir) = self.shared.paths.custom_agents_dir.clone() else {
             return Err(IdeError::unavailable("there is no custom agents directory"));
         };
-        provider::set_builtin_env(&dir, id, env)
+        provider::set_builtin_env(&dir, self.shared.env_secrets(), id, env)
     }
 
     /// Saves a new custom ACP agent through its agent file.
@@ -553,7 +584,7 @@ impl AgentManager {
         let Some(dir) = self.shared.paths.custom_agents_dir.clone() else {
             return Err(IdeError::unavailable("there is no custom agents directory"));
         };
-        provider::save_custom(&dir, &input)
+        provider::save_custom(&dir, self.shared.env_secrets(), &input)
     }
 
     /// Removes a custom agent's file (registry installs go through `registry_remove`).
@@ -561,7 +592,7 @@ impl AgentManager {
         let Some(dir) = self.shared.paths.custom_agents_dir.clone() else {
             return Err(IdeError::unavailable("there is no custom agents directory"));
         };
-        provider::remove_custom(&dir, id)
+        provider::remove_custom(&dir, self.shared.env_secrets(), id)
     }
 
     /// Imports a JetBrains `acp.json` file's `agent_servers` entries as custom agents.
@@ -569,12 +600,12 @@ impl AgentManager {
         let Some(dir) = self.shared.paths.custom_agents_dir.clone() else {
             return Err(IdeError::unavailable("there is no custom agents directory"));
         };
-        provider::import_acp(&dir, text)
+        provider::import_acp(&dir, self.shared.env_secrets(), text)
     }
 
     /// Re-reads configured/installed agents, drops cached probes, and notifies subscribers.
     pub fn reload_providers(&self) {
-        let specs = provider::load(self.shared.paths.custom_agents_dir.as_deref());
+        let specs = provider::load(self.shared.paths.custom_agents_dir.as_deref(), self.shared.env_secrets());
         *self.shared.providers.write() = specs;
         self.shared.probes.lock().clear();
         self.shared.emit(AgentEvent::Providers);
@@ -2266,15 +2297,19 @@ impl Task {
             .iter()
             .map(|question| question.answer_key.clone().unwrap_or_else(|| question.question.clone()))
             .collect();
+        let command = security::extract_command(params);
+        // What the card names as the command: not for a request that grants more than running it.
+        let shown = command.as_deref().filter(|_| !security::widens_access(params)).map(shown_command);
         if let Some(hook) = self.shared.security.read().clone()
-            && let Some(command) = security::extract_command(params)
+            && let Some(command) = command.as_deref()
         {
-            match security::evaluate_command(&command, &hook()) {
+            match security::evaluate_command(command, &hook()) {
                 security::PolicyDecision::Blocked(pattern) => {
                     let reject = options.iter().find(|o| o.kind.starts_with("reject")).cloned();
                     let _ = self.push_entry(AgentEntry::Permission {
                         id,
                         title,
+                        command: shown.clone(),
                         options,
                         questions: Vec::new(),
                         chosen: Some(format!("Blocked by policy ({pattern})")),
@@ -2284,7 +2319,7 @@ impl Task {
                         None => json!({ "outcome": { "outcome": "cancelled" } }),
                     };
                 }
-                security::PolicyDecision::Allowed => {
+                security::PolicyDecision::Allowed if !security::widens_access(params) => {
                     if let Some(allow) = options
                         .iter()
                         .find(|o| o.kind == "allow_once")
@@ -2294,6 +2329,7 @@ impl Task {
                         let _ = self.push_entry(AgentEntry::Permission {
                             id,
                             title,
+                            command: shown.clone(),
                             options,
                             questions: Vec::new(),
                             chosen: Some(format!("{} (whitelisted)", allow.name)),
@@ -2301,12 +2337,18 @@ impl Task {
                         return json!({ "outcome": { "outcome": "selected", "optionId": allow.id } });
                     }
                 }
-                security::PolicyDecision::AskUser => {}
+                security::PolicyDecision::Allowed | security::PolicyDecision::AskUser => {}
             }
         }
         let (tx, rx) = std::sync::mpsc::channel();
-        let entry =
-            self.push_entry(AgentEntry::Permission { id, title, options: options.clone(), questions, chosen: None });
+        let entry = self.push_entry(AgentEntry::Permission {
+            id,
+            title,
+            command: shown,
+            options: options.clone(),
+            questions,
+            chosen: None,
+        });
         self.permissions.lock().insert(id, tx);
         self.set_status(AgentStatus::NeedsInput, None);
         self.approve_pending();
@@ -2468,6 +2510,11 @@ fn permission_title(params: &Value) -> String {
     title.unwrap_or("The agent asks for permission").to_owned()
 }
 
+/// A command as a permission card shows it: the script of a `<shell> -c <script>` line.
+fn shown_command(command: &str) -> String {
+    shell_script(command).unwrap_or_else(|| command.to_owned())
+}
+
 /// The script of a `<shell> -c <quoted script>` command line, when the whole line is exactly that.
 pub(crate) fn shell_script(command: &str) -> Option<String> {
     let (shell, rest) = command.split_once(' ')?;

crates/ide-agent/src/model.rs

@@ -384,6 +384,10 @@ pub enum AgentEntry {
     Permission {
         id: u32,
         title: String,
+        /// The shell command the request asks to run, from its structured input; `None` for
+        /// any other request, whatever its title says.
+        #[serde(default)]
+        command: Option<String>,
         options: Vec<AgentPermissionOption>,
         /// Set when the request asks `AskUserQuestion`'s questions; answered with a JSON object
         /// of question to answer instead of an option.

crates/ide-agent/src/native/codex/mod.rs

@@ -869,13 +869,14 @@ impl CodexShim {
             "item/commandExecution/requestApproval" => {
                 let choices = translate::decisions(params, true);
                 let title = translate::command_approval_title(params, item.as_ref());
-                let call = tool_call_of(
-                    &item_id,
-                    &title,
-                    "execute",
-                    reason,
-                    Some(json!({ "command": params.get("command"), "cwd": params.get("cwd") })),
-                );
+                let mut input = json!({
+                    "command": translate::approval_command(params, item.as_ref()),
+                    "cwd": params.get("cwd"),
+                });
+                if let Some(network) = params.get("networkApprovalContext").filter(|c| !c.is_null()) {
+                    input["networkApprovalContext"] = network.clone();
+                }
+                let call = tool_call_of(&item_id, &title, "execute", reason, Some(input));
                 Ok(self.ask(&thread, call, &choices, decline))
             }
             "item/fileChange/requestApproval" => {

crates/ide-agent/src/native/codex/translate.rs

@@ -757,19 +757,23 @@ pub(super) fn answer_of(choices: &[Choice], outcome: &Value, decline: Value) ->
     choices.iter().find(|c| selected && c.option["optionId"].as_str() == chosen).map_or(decline, |c| c.answer.clone())
 }
 
+/// The command a command approval is about: the request's own, else its item's.
+pub(super) fn approval_command<'a>(params: &'a Value, item: Option<&'a Value>) -> Option<&'a str> {
+    // Approval payloads can describe a different command from the item's earlier summary.
+    let item = item.filter(|i| i.get("id") == params.get("itemId"));
+    params
+        .get("command")
+        .and_then(Value::as_str)
+        .filter(|c| !c.is_empty())
+        .or_else(|| item.and_then(|i| i.get("command")).and_then(Value::as_str).filter(|c| !c.is_empty()))
+}
+
 /// The ACP title of a command approval.
 pub(super) fn command_approval_title(params: &Value, item: Option<&Value>) -> String {
     if let Some(host) = params.pointer("/networkApprovalContext/host").and_then(Value::as_str) {
         return format!("Allow network access to {host}");
     }
-    // Approval payloads can describe a different command from the item's earlier summary.
-    let item = item.filter(|i| i.get("id") == params.get("itemId"));
-    let command = params
-        .get("command")
-        .and_then(Value::as_str)
-        .filter(|c| !c.is_empty())
-        .or_else(|| item.and_then(|i| i.get("command")).and_then(Value::as_str).filter(|c| !c.is_empty()));
-    match command {
+    match approval_command(params, item) {
         Some(command) => format!("Run {}", crate::shell_script(command).unwrap_or_else(|| command.to_owned())),
         None => "Run a command".to_owned(),
     }

crates/ide-agent/src/provider.rs

@@ -2,7 +2,7 @@
 //! `<config>/agents/<id>.toml` (written by hand, or by installing one from the ACP
 //! Registry, see `registry`).
 
-use crate::{AcpImportOutcome, AgentCommandReadOnlyReason, AgentProvider, AgentSource, CustomAgentInput};
+use crate::{AcpImportOutcome, AgentCommandReadOnlyReason, AgentProvider, AgentSource, CustomAgentInput, EnvSecrets};
 use ide_core::{IdeError, IdeResult};
 use serde::{Deserialize, Serialize};
 use serde_json::Value;
@@ -231,23 +231,40 @@ pub(crate) fn describe(spec: &ProviderSpec) -> AgentProvider {
 
 /// Overrides built-in `id`'s command through its agent file, preserving other
 /// customizations. `None` restores the built-in command and removes a redundant file.
-pub(crate) fn set_builtin_command(custom_dir: &Path, id: &str, command: Option<&str>) -> IdeResult<()> {
-    update_builtin(custom_dir, id, |agent, builtin| agent.command = command.unwrap_or(&builtin.command).to_owned())
+pub(crate) fn set_builtin_command(
+    custom_dir: &Path,
+    secrets: Option<&dyn EnvSecrets>,
+    id: &str,
+    command: Option<&str>,
+) -> IdeResult<()> {
+    update_builtin(custom_dir, secrets, id, |agent, builtin| {
+        agent.command = command.unwrap_or(&builtin.command).to_owned()
+    })
 }
 
 /// The environment built-in `id` starts with, through its agent file (empty clears it).
-pub(crate) fn set_builtin_env(custom_dir: &Path, id: &str, env: BTreeMap<String, String>) -> IdeResult<()> {
-    update_builtin(custom_dir, id, |agent, _| agent.env = env)
+pub(crate) fn set_builtin_env(
+    custom_dir: &Path,
+    secrets: Option<&dyn EnvSecrets>,
+    id: &str,
+    env: BTreeMap<String, String>,
+) -> IdeResult<()> {
+    update_builtin(custom_dir, secrets, id, |agent, _| agent.env = env)
 }
 
 /// Changes built-in `id`'s agent file; a file left with only the built-in's values is removed.
-fn update_builtin(custom_dir: &Path, id: &str, change: impl FnOnce(&mut CustomAgent, &ProviderSpec)) -> IdeResult<()> {
+fn update_builtin(
+    custom_dir: &Path,
+    secrets: Option<&dyn EnvSecrets>,
+    id: &str,
+    change: impl FnOnce(&mut CustomAgent, &ProviderSpec),
+) -> IdeResult<()> {
     let Some(builtin) = builtin_spec(id) else {
         return Err(IdeError::invalid(format!("{id} is not a built-in agent")));
     };
     let file = custom_dir.join(format!("{id}.toml"));
     let mut agent = if file.try_exists()? {
-        CustomAgent::read(&file).map_err(IdeError::invalid)?
+        CustomAgent::read_with(&file, id, secrets).map_err(IdeError::invalid)?
     } else {
         CustomAgent {
             name: Some(builtin.name.clone()),
@@ -272,16 +289,20 @@ fn update_builtin(custom_dir: &Path, id: &str, change: impl FnOnce(&mut CustomAg
             Err(e) if e.kind() != std::io::ErrorKind::NotFound => return Err(e.into()),
             _ => {}
         }
+        forget_env(secrets, id, &[]);
         return Ok(());
     }
-    agent.write(&file)?;
-    Ok(())
+    agent.write_with(&file, id, secrets)
 }
 
 /// Saves a new custom agent; refuses built-in and ACP Registry ids, taken ids
 /// and an empty command. The id is also the agent file's name, so it must be
 /// a safe file stem.
-pub(crate) fn save_custom(custom_dir: &Path, input: &CustomAgentInput) -> IdeResult<()> {
+pub(crate) fn save_custom(
+    custom_dir: &Path,
+    secrets: Option<&dyn EnvSecrets>,
+    input: &CustomAgentInput,
+) -> IdeResult<()> {
     let id = validated_custom_id(&input.id)?;
     if builtin_spec(&id).is_some() {
         return Err(IdeError::invalid(format!("{id} is a built-in agent; change its command instead")));
@@ -306,12 +327,11 @@ pub(crate) fn save_custom(custom_dir: &Path, input: &CustomAgentInput) -> IdeRes
         env: input.env.clone(),
         registry: None,
     }
-    .write(&file)?;
-    Ok(())
+    .write_with(&file, &id, secrets)
 }
 
 /// Removes a custom agent's file; refuses built-in, ACP Registry and missing ids.
-pub(crate) fn remove_custom(custom_dir: &Path, id: &str) -> IdeResult<()> {
+pub(crate) fn remove_custom(custom_dir: &Path, secrets: Option<&dyn EnvSecrets>, id: &str) -> IdeResult<()> {
     let id = validated_custom_id(id)?;
     let id = id.as_str();
     if builtin_spec(id).is_some() {
@@ -325,14 +345,21 @@ pub(crate) fn remove_custom(custom_dir: &Path, id: &str) -> IdeResult<()> {
     }
     match std::fs::remove_file(&file) {
         Err(e) if e.kind() != std::io::ErrorKind::NotFound => Err(e.into()),
-        _ => Ok(()),
+        _ => {
+            forget_env(secrets, id, &[]);
+            Ok(())
+        }
     }
 }
 
 /// Imports a JetBrains `acp.json` file's `agent_servers` entries as custom
 /// agents, one outcome per entry; entries that collide, lack a command or
 /// have no usable name are skipped with a reason.
-pub(crate) fn import_acp(custom_dir: &Path, text: &str) -> IdeResult<Vec<AcpImportOutcome>> {
+pub(crate) fn import_acp(
+    custom_dir: &Path,
+    secrets: Option<&dyn EnvSecrets>,
+    text: &str,
+) -> IdeResult<Vec<AcpImportOutcome>> {
     #[derive(Deserialize)]
     struct AcpJson {
         #[serde(default)]
@@ -370,7 +397,7 @@ pub(crate) fn import_acp(custom_dir: &Path, text: &str) -> IdeResult<Vec<AcpImpo
                 env: server.env,
                 registry: None,
             }
-            .write(&custom_dir.join(format!("{id}.toml")))?;
+            .write_with(&custom_dir.join(format!("{id}.toml")), &id, secrets)?;
             outcome.saved = true;
         }
         outcomes.push(outcome);
@@ -400,7 +427,7 @@ fn slugify_id(name: &str) -> String {
 }
 
 /// An agent file, `<config>/agents/<id>.toml`.
-#[derive(Debug, PartialEq, Serialize, Deserialize)]
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
 #[serde(deny_unknown_fields)]
 pub(crate) struct CustomAgent {
     #[serde(default, skip_serializing_if = "Option::is_none")]
@@ -447,11 +474,67 @@ impl CustomAgent {
         std::fs::write(&tmp, text)?;
         std::fs::rename(&tmp, path)
     }
+
+    /// Reads agent `id`'s file with its environment values filled in from `secrets`; values
+    /// still written in the file (by hand, by an older version) move there first. A registry
+    /// install keeps the environment its registry entry gives it in the file.
+    pub(crate) fn read_with(path: &Path, id: &str, secrets: Option<&dyn EnvSecrets>) -> Result<Self, String> {
+        let mut agent = Self::read(path)?;
+        let Some(secrets) = secrets.filter(|_| agent.registry.is_none()) else {
+            return Ok(agent);
+        };
+        let written = agent.env.values().any(|v| !v.is_empty());
+        for (name, value) in agent.env.iter_mut() {
+            if value.is_empty()
+                && let Some(saved) = secrets.get(&env_key(id, name))
+            {
+                *value = saved;
+            }
+        }
+        if written && let Err(e) = agent.write_with(path, id, Some(secrets)) {
+            tracing::warn!("agent {id}: could not move environment values out of {}: {}", path.display(), e.message);
+        }
+        Ok(agent)
+    }
+
+    /// Writes agent `id`'s file with the environment's names only, its values saved in `secrets`.
+    pub(crate) fn write_with(&self, path: &Path, id: &str, secrets: Option<&dyn EnvSecrets>) -> IdeResult<()> {
+        let Some(secrets) = secrets.filter(|_| self.registry.is_none()) else {
+            return Ok(self.write(path)?);
+        };
+        let mut keys = Vec::with_capacity(self.env.len());
+        for (name, value) in &self.env {
+            let key = env_key(id, name);
+            if value.is_empty() {
+                secrets.delete(&key);
+            } else if secrets.get(&key).as_deref() != Some(value.as_str()) {
+                secrets.set(&key, value)?;
+            }
+            keys.push(key);
+        }
+        forget_env(Some(secrets), id, &keys);
+        let names = self.env.keys().map(|name| (name.clone(), String::new())).collect();
+        Ok(Self { env: names, ..self.clone() }.write(path)?)
+    }
+}
+
+fn env_key(id: &str, name: &str) -> String {
+    format!("agent/{id}/env/{}", name.replace('%', "%25").replace('/', "%2F"))
+}
+
+/// Forgets agent `id`'s saved environment values, except `keep`.
+fn forget_env(secrets: Option<&dyn EnvSecrets>, id: &str, keep: &[String]) {
+    let Some(secrets) = secrets else { return };
+    for key in secrets.keys(&format!("agent/{id}/env/")) {
+        if !keep.contains(&key) {
+            secrets.delete(&key);
+        }
+    }
 }
 
 /// Built-in agents, then the `*.toml` agents of `custom_dir`; a custom agent with a
 /// built-in id replaces it.
-pub(crate) fn load(custom_dir: Option<&Path>) -> Vec<ProviderSpec> {
+pub(crate) fn load(custom_dir: Option<&Path>, secrets: Option<&dyn EnvSecrets>) -> Vec<ProviderSpec> {
     let mut specs = builtins();
     let mut files: Vec<PathBuf> = custom_dir
         .and_then(|d| std::fs::read_dir(d).ok())
@@ -464,7 +547,7 @@ pub(crate) fn load(custom_dir: Option<&Path>) -> Vec<ProviderSpec> {
     files.sort();
     for path in files {
         let Some(id) = path.file_stem().and_then(|s| s.to_str()).map(str::to_owned) else { continue };
-        let agent = match CustomAgent::read(&path) {
+        let agent = match CustomAgent::read_with(&path, &id, secrets) {
             Ok(a) => a,
             Err(e) => {
                 tracing::warn!("skipping agent {}: {e}", path.display());
@@ -534,7 +617,7 @@ mod tests {
 
     #[test]
     fn qoder_global_and_cn_editions_are_both_built_in() {
-        let info = |id: &str| describe(&load(None).into_iter().find(|s| s.id == id).unwrap());
+        let info = |id: &str| describe(&load(None, None).into_iter().find(|s| s.id == id).unwrap());
         let (global, cn) = (info("qoder"), info("qodercn"));
         assert_eq!((global.name.as_str(), global.command.as_str()), ("Qoder", "qodercli --acp"));
         assert_eq!((cn.name.as_str(), cn.command.as_str()), ("Qoder CN", "qoderclicn --acp"));
@@ -544,7 +627,7 @@ mod tests {
     #[test]
     fn qodercn_is_available_without_a_file_and_preserves_existing_customizations() {
         let dir = tempfile::tempdir().unwrap();
-        let qodercn = load(None).into_iter().find(|s| s.id == "qodercn").unwrap();
+        let qodercn = load(None, None).into_iter().find(|s| s.id == "qodercn").unwrap();
         assert_eq!(qodercn.driver, Driver::Acp);
         assert!(!is_unlisted(&qodercn));
         let info = describe(&qodercn);
@@ -559,13 +642,13 @@ mod tests {
             "command = \"/custom/qoderclicn\"\nargs = [\"--acp\"]\n[env]\nK = \"v\"\n",
         )
         .unwrap();
-        let specs = load(Some(dir.path()));
+        let specs = load(Some(dir.path()), None);
         assert_eq!(specs.iter().filter(|s| s.id == "qodercn").count(), 1);
         let custom = specs.iter().find(|s| s.id == "qodercn").unwrap();
         assert_eq!(custom.command, "/custom/qoderclicn");
         assert_eq!(custom.env, [("K".into(), "v".into())]);
-        set_builtin_command(dir.path(), "qodercn", None).unwrap();
-        let reset = load(Some(dir.path())).into_iter().find(|s| s.id == "qodercn").unwrap();
+        set_builtin_command(dir.path(), None, "qodercn", None).unwrap();
+        let reset = load(Some(dir.path()), None).into_iter().find(|s| s.id == "qodercn").unwrap();
         assert_eq!(reset.command, "qoderclicn");
         assert_eq!(reset.args, ["--acp"]);
         assert_eq!(reset.env, custom.env);
@@ -680,7 +763,7 @@ mod tests {
     #[test]
     fn launch_metadata_distinguishes_defaults_overrides_and_read_only_agents() {
         let dir = tempfile::tempdir().unwrap();
-        let list = || load(Some(dir.path())).iter().map(describe).collect::<Vec<_>>();
+        let list = || load(Some(dir.path()), None).iter().map(describe).collect::<Vec<_>>();
         let defaults = list();
         let codex = defaults.iter().find(|p| p.id == "codex").unwrap();
         assert_eq!(codex.program, "codex");
@@ -700,14 +783,14 @@ mod tests {
                 p.id.ends_with("-acp").then_some(AgentCommandReadOnlyReason::PackageRunner)
             );
         }
-        set_builtin_command(dir.path(), "codex", Some("/path with spaces/codex")).unwrap();
+        set_builtin_command(dir.path(), None, "codex", Some("/path with spaces/codex")).unwrap();
         let overridden = list().into_iter().find(|p| p.id == "codex").unwrap();
         assert_eq!(overridden.program, "/path with spaces/codex");
         assert_eq!(overridden.args, codex.args);
         assert_eq!(overridden.default_program, codex.default_program);
         assert!(overridden.command_overridden && overridden.command_editable);
         assert_eq!(overridden.source, AgentSource::Builtin);
-        set_builtin_command(dir.path(), "codex", Some("codex")).unwrap();
+        set_builtin_command(dir.path(), None, "codex", Some("codex")).unwrap();
         assert!(!list().iter().find(|p| p.id == "codex").unwrap().command_overridden);
         std::fs::write(
             dir.path().join("gemini.toml"),
@@ -732,7 +815,7 @@ mod tests {
         write("mine.toml", "name = \"Mine\"\ncommand = \"/opt/mine\"\nargs = [\"acp\"]\n[env]\nK = \"v\"\n");
         write("gemini.toml", "command = \"gemini\"\nargs = [\"--acp\"]\n");
         write("broken.toml", "nope = 1\n");
-        let specs = load(Some(dir.path()));
+        let specs = load(Some(dir.path()), None);
         let mine = specs.iter().find(|s| s.id == "mine").unwrap();
         assert_eq!((mine.name.as_str(), mine.command.as_str()), ("Mine", "/opt/mine"));
         assert_eq!(mine.env, vec![("K".to_owned(), "v".to_owned())]);
@@ -748,34 +831,35 @@ mod tests {
     fn set_builtin_env_writes_and_clears_the_environment() {
         let dir = tempfile::tempdir().unwrap();
         let env = BTreeMap::from([("CLAUDE_CODE_ENTRYPOINT".to_owned(), "openidea".to_owned())]);
-        set_builtin_env(dir.path(), "claude", env.clone()).unwrap();
-        let claude = load(Some(dir.path())).into_iter().find(|s| s.id == "claude").unwrap();
+        set_builtin_env(dir.path(), None, "claude", env.clone()).unwrap();
+        let claude = load(Some(dir.path()), None).into_iter().find(|s| s.id == "claude").unwrap();
         assert_eq!(claude.env, vec![("CLAUDE_CODE_ENTRYPOINT".to_owned(), "openidea".to_owned())]);
         assert_eq!(describe(&claude).env, env);
         // The command override and the environment are kept independently.
-        set_builtin_command(dir.path(), "claude", Some("/opt/claude")).unwrap();
-        set_builtin_command(dir.path(), "claude", None).unwrap();
+        set_builtin_command(dir.path(), None, "claude", Some("/opt/claude")).unwrap();
+        set_builtin_command(dir.path(), None, "claude", None).unwrap();
         assert!(dir.path().join("claude.toml").is_file());
-        set_builtin_env(dir.path(), "claude", BTreeMap::new()).unwrap();
+        set_builtin_env(dir.path(), None, "claude", BTreeMap::new()).unwrap();
         assert!(!dir.path().join("claude.toml").exists());
-        set_builtin_env(dir.path(), "not-a-builtin", env).unwrap_err();
+        set_builtin_env(dir.path(), None, "not-a-builtin", env).unwrap_err();
     }
 
     #[test]
     fn acp_adapters_of_native_agents_are_unlisted_until_customized() {
         let dir = tempfile::tempdir().unwrap();
-        let unlisted = |dir: &Path| load(Some(dir)).into_iter().filter(is_unlisted).map(|s| s.id).collect::<Vec<_>>();
+        let unlisted =
+            |dir: &Path| load(Some(dir), None).into_iter().filter(is_unlisted).map(|s| s.id).collect::<Vec<_>>();
         assert_eq!(unlisted(dir.path()), ["claude-acp", "codex-acp"]);
-        set_builtin_env(dir.path(), "codex-acp", BTreeMap::from([("A".to_owned(), "1".to_owned())])).unwrap();
+        set_builtin_env(dir.path(), None, "codex-acp", BTreeMap::from([("A".to_owned(), "1".to_owned())])).unwrap();
         assert_eq!(unlisted(dir.path()), ["claude-acp"]);
     }
 
     #[test]
     fn set_builtin_command_overrides_and_clears_a_builtin() {
         let dir = tempfile::tempdir().unwrap();
-        set_builtin_command(dir.path(), "not-a-builtin", Some("/x")).unwrap_err();
-        set_builtin_command(dir.path(), "claude", Some("/opt/claude")).unwrap();
-        let claude = load(Some(dir.path())).into_iter().find(|s| s.id == "claude").unwrap();
+        set_builtin_command(dir.path(), None, "not-a-builtin", Some("/x")).unwrap_err();
+        set_builtin_command(dir.path(), None, "claude", Some("/opt/claude")).unwrap();
+        let claude = load(Some(dir.path()), None).into_iter().find(|s| s.id == "claude").unwrap();
         assert_eq!((claude.command.as_str(), claude.driver), ("/opt/claude", Driver::Claude));
         assert!(claude.args.is_empty());
         // A registry install is neither overwritten nor removed by a command override.
@@ -790,14 +874,14 @@ mod tests {
         }
         .write(&path)
         .unwrap();
-        set_builtin_command(dir.path(), "codex", Some("/x")).unwrap_err();
-        set_builtin_command(dir.path(), "codex", None).unwrap_err();
+        set_builtin_command(dir.path(), None, "codex", Some("/x")).unwrap_err();
+        set_builtin_command(dir.path(), None, "codex", None).unwrap_err();
         assert!(path.exists());
         // Clearing (twice) returns the built-in to auto-detection.
-        set_builtin_command(dir.path(), "claude", None).unwrap();
-        set_builtin_command(dir.path(), "claude", None).unwrap();
+        set_builtin_command(dir.path(), None, "claude", None).unwrap();
+        set_builtin_command(dir.path(), None, "claude", None).unwrap();
         assert!(!dir.path().join("claude.toml").exists());
-        assert_eq!(load(Some(dir.path())).iter().find(|s| s.id == "claude").unwrap().command, "claude");
+        assert_eq!(load(Some(dir.path()), None).iter().find(|s| s.id == "claude").unwrap().command, "claude");
     }
 
     #[test]
@@ -825,11 +909,11 @@ mod tests {
             }
             agent.write(&path).unwrap();
 
-            set_builtin_command(dir.path(), "claude", Some("/new/claude")).unwrap();
+            set_builtin_command(dir.path(), None, "claude", Some("/new/claude")).unwrap();
             agent.command = "/new/claude".into();
             assert_eq!(CustomAgent::read(&path).unwrap(), agent, "{field}");
 
-            set_builtin_command(dir.path(), "claude", None).unwrap();
+            set_builtin_command(dir.path(), None, "claude", None).unwrap();
             agent.command = "claude".into();
             assert_eq!(CustomAgent::read(&path).unwrap(), agent, "{field}");
         }
@@ -845,11 +929,11 @@ mod tests {
         )
         .unwrap();
 
-        set_builtin_command(dir.path(), "codex", None).unwrap();
+        set_builtin_command(dir.path(), None, "codex", None).unwrap();
 
         assert!(!path.exists());
         assert_eq!(
-            load(Some(dir.path())).into_iter().find(|s| s.id == "codex").unwrap(),
+            load(Some(dir.path()), None).into_iter().find(|s| s.id == "codex").unwrap(),
             builtin_spec("codex").unwrap()
         );
     }
@@ -870,7 +954,7 @@ mod tests {
         let text = std::fs::read_to_string(&path).unwrap();
         assert!(text.contains("[registry]") && !text.contains("driver"), "{text}");
         assert_eq!(CustomAgent::read(&path).unwrap(), agent);
-        let spec = load(Some(path.parent().unwrap())).into_iter().find(|s| s.id == "amp-acp").unwrap();
+        let spec = load(Some(path.parent().unwrap()), None).into_iter().find(|s| s.id == "amp-acp").unwrap();
         assert_eq!(spec.source, AgentSource::Registry { version: "0.10.0".into(), update: None });
         assert!(toml::from_str::<CustomAgent>("command = \"x\"\n[registry]\nid = \"x\"\n").is_err());
     }
@@ -888,50 +972,117 @@ mod tests {
     #[test]
     fn custom_agents_save_list_and_remove() {
         let dir = tempfile::tempdir().unwrap();
-        save_custom(dir.path(), &custom_input("mine")).unwrap();
-        let mine = load(Some(dir.path())).into_iter().find(|s| s.id == "mine").unwrap();
+        save_custom(dir.path(), None, &custom_input("mine")).unwrap();
+        let mine = load(Some(dir.path()), None).into_iter().find(|s| s.id == "mine").unwrap();
         assert_eq!((mine.name.as_str(), mine.command.as_str()), ("Mine", "/opt/mine"));
         assert_eq!(mine.env, vec![("K".to_owned(), "v".to_owned())]);
         assert_eq!(mine.source, AgentSource::Custom);
-        remove_custom(dir.path(), "mine").unwrap();
-        assert!(!load(Some(dir.path())).iter().any(|s| s.id == "mine"));
-        remove_custom(dir.path(), "mine").unwrap_err();
+        remove_custom(dir.path(), None, "mine").unwrap();
+        assert!(!load(Some(dir.path()), None).iter().any(|s| s.id == "mine"));
+        remove_custom(dir.path(), None, "mine").unwrap_err();
     }
 
     #[test]
     fn custom_agents_refuse_builtin_registry_and_bad_ids() {
         let dir = tempfile::tempdir().unwrap();
-        save_custom(dir.path(), &custom_input("claude")).unwrap_err();
-        save_custom(dir.path(), &custom_input("../evil")).unwrap_err();
-        save_custom(dir.path(), &custom_input("")).unwrap_err();
+        save_custom(dir.path(), None, &custom_input("claude")).unwrap_err();
+        save_custom(dir.path(), None, &custom_input("../evil")).unwrap_err();
+        save_custom(dir.path(), None, &custom_input("")).unwrap_err();
         let mut empty_command = custom_input("mine");
         empty_command.command = "  ".into();
-        save_custom(dir.path(), &empty_command).unwrap_err();
-        save_custom(dir.path(), &custom_input("mine")).unwrap();
-        save_custom(dir.path(), &custom_input("mine")).unwrap_err();
-        remove_custom(dir.path(), "claude").unwrap_err();
+        save_custom(dir.path(), None, &empty_command).unwrap_err();
+        save_custom(dir.path(), None, &custom_input("mine")).unwrap();
+        save_custom(dir.path(), None, &custom_input("mine")).unwrap_err();
+        remove_custom(dir.path(), None, "claude").unwrap_err();
         // An id that isn't a plain file stem never reaches outside the agents directory.
         let outside = dir.path().join("outside.toml");
         std::fs::write(&outside, "command = \"/bin/sh\"\n").unwrap();
         let agents = dir.path().join("agents");
         std::fs::create_dir(&agents).unwrap();
-        remove_custom(&agents, "../outside").unwrap_err();
+        remove_custom(&agents, None, "../outside").unwrap_err();
         assert!(outside.exists());
         std::fs::write(
             dir.path().join("amp-acp.toml"),
             "command = \"/registry/amp\"\n[registry]\nid = \"amp-acp\"\nversion = \"1.0\"\n",
         )
         .unwrap();
-        save_custom(dir.path(), &custom_input("amp-acp")).unwrap_err();
-        remove_custom(dir.path(), "amp-acp").unwrap_err();
+        save_custom(dir.path(), None, &custom_input("amp-acp")).unwrap_err();
+        remove_custom(dir.path(), None, "amp-acp").unwrap_err();
+    }
+
+    #[derive(Default)]
+    struct MemorySecrets(parking_lot::Mutex<BTreeMap<String, String>>);
+
+    impl EnvSecrets for MemorySecrets {
+        fn get(&self, key: &str) -> Option<String> {
+            self.0.lock().get(key).cloned()
+        }
+        fn set(&self, key: &str, value: &str) -> IdeResult<()> {
+            self.0.lock().insert(key.to_owned(), value.to_owned());
+            Ok(())
+        }
+        fn delete(&self, key: &str) {
+            self.0.lock().remove(key);
+        }
+        fn keys(&self, prefix: &str) -> Vec<String> {
+            self.0.lock().keys().filter(|k| k.starts_with(prefix)).cloned().collect()
+        }
+    }
+
+    #[test]
+    fn environment_values_go_to_the_secrets_and_the_files_keep_the_names() {
+        let dir = tempfile::tempdir().unwrap();
+        let secrets = MemorySecrets::default();
+        let s = Some(&secrets as &dyn EnvSecrets);
+        let env = BTreeMap::from([("API_KEY".to_owned(), "v-91f".to_owned()), ("A/B".to_owned(), String::new())]);
+        set_builtin_env(dir.path(), s, "claude", env.clone()).unwrap();
+        save_custom(dir.path(), s, &CustomAgentInput { env: env.clone(), ..custom_input("mine") }).unwrap();
+        for id in ["claude", "mine"] {
+            let text = std::fs::read_to_string(dir.path().join(format!("{id}.toml"))).unwrap();
+            assert!(text.contains("API_KEY") && !text.contains("v-91f"), "{text}");
+            let spec = load(Some(dir.path()), s).into_iter().find(|p| p.id == id).unwrap();
+            assert_eq!(describe(&spec).env, env);
+        }
+        assert_eq!(secrets.keys("agent/"), ["agent/claude/env/API_KEY", "agent/mine/env/API_KEY"]);
+
+        set_builtin_command(dir.path(), s, "claude", Some("/opt/claude")).unwrap();
+        assert_eq!(secrets.get("agent/claude/env/API_KEY").as_deref(), Some("v-91f"));
+        set_builtin_env(dir.path(), s, "claude", BTreeMap::from([("OTHER".to_owned(), "x".to_owned())])).unwrap();
+        assert_eq!(secrets.keys("agent/claude/"), ["agent/claude/env/OTHER"]);
+        set_builtin_command(dir.path(), s, "claude", None).unwrap();
+        set_builtin_env(dir.path(), s, "claude", BTreeMap::new()).unwrap();
+        remove_custom(dir.path(), s, "mine").unwrap();
+        assert_eq!(secrets.keys("agent/"), Vec::<String>::new());
+    }
+
+    #[test]
+    fn values_written_in_agent_files_move_to_the_secrets_unless_installed_from_the_registry() {
+        let dir = tempfile::tempdir().unwrap();
+        let secrets = MemorySecrets::default();
+        let s = Some(&secrets as &dyn EnvSecrets);
+        std::fs::write(dir.path().join("mine.toml"), "command = \"/opt/mine\"\n[env]\nK = \"v-91f\"\nS = \"\"\n")
+            .unwrap();
+        secrets.set("agent/mine/env/S", "saved").unwrap();
+        let registry =
+            "command = \"/registry/amp\"\n[env]\nR = \"1\"\n[registry]\nid = \"amp-acp\"\nversion = \"1.0\"\n";
+        std::fs::write(dir.path().join("amp-acp.toml"), registry).unwrap();
+        let specs = load(Some(dir.path()), s);
+        assert_eq!(
+            specs.iter().find(|p| p.id == "mine").unwrap().env,
+            [("K".to_owned(), "v-91f".to_owned()), ("S".to_owned(), "saved".to_owned())]
+        );
+        assert!(!std::fs::read_to_string(dir.path().join("mine.toml")).unwrap().contains("v-91f"));
+        assert_eq!(secrets.keys("agent/"), ["agent/mine/env/K", "agent/mine/env/S"]);
+        assert_eq!(std::fs::read_to_string(dir.path().join("amp-acp.toml")).unwrap(), registry);
     }
 
     #[test]
     fn acp_json_imports_servers_and_skips_collisions() {
         let dir = tempfile::tempdir().unwrap();
-        save_custom(dir.path(), &custom_input("taken")).unwrap();
+        save_custom(dir.path(), None, &custom_input("taken")).unwrap();
         let outcomes = import_acp(
             dir.path(),
+            None,
             r#"{"agent_servers": {
                 "My Agent!": {"command": "/opt/agent", "args": ["--acp"], "env": {"K": "v"}},
                 "taken": {"command": "/opt/taken"},
@@ -944,10 +1095,10 @@ mod tests {
         let saved: Vec<&str> = outcomes.iter().filter(|o| o.saved).map(|o| o.id.as_str()).collect();
         assert_eq!(saved, ["my-agent"]);
         assert!(outcomes.iter().filter(|o| !o.saved).all(|o| !o.reason.is_empty()));
-        let mine = load(Some(dir.path())).into_iter().find(|s| s.id == "my-agent").unwrap();
+        let mine = load(Some(dir.path()), None).into_iter().find(|s| s.id == "my-agent").unwrap();
         assert_eq!((mine.name.as_str(), mine.command.as_str()), ("My Agent!", "/opt/agent"));
         assert_eq!(mine.source, AgentSource::Custom);
-        import_acp(dir.path(), "not json").unwrap_err();
-        assert!(import_acp(dir.path(), "{}").unwrap().is_empty());
+        import_acp(dir.path(), None, "not json").unwrap_err();
+        assert!(import_acp(dir.path(), None, "{}").unwrap().is_empty());
     }
 }

crates/ide-agent/src/registry.rs

@@ -826,7 +826,7 @@ mod tests {
         assert!(!shown.iter().any(|a| a.id == "cline"));
 
         write_atomic(&p.cache_file, INDEX.as_bytes()).unwrap();
-        let mut providers: Vec<AgentProvider> = provider::load(Some(&p.agents_dir))
+        let mut providers: Vec<AgentProvider> = provider::load(Some(&p.agents_dir), None)
             .into_iter()
             .filter(|s| s.id == "amp-acp")
             .map(|s| provider::describe(&s))
@@ -918,7 +918,7 @@ mod tests {
         assert_eq!(agent.command, v1.to_string_lossy());
         assert_eq!((agent.args.as_slice(), agent.env["A"].as_str()), (&["acp".to_owned()][..], "1"));
         assert_eq!(agent.registry, Some(RegistryRef { id: "demo".into(), version: "1.0.0".into() }));
-        let spec = provider::load(Some(&p.agents_dir)).into_iter().find(|s| s.id == "demo").unwrap();
+        let spec = provider::load(Some(&p.agents_dir), None).into_iter().find(|s| s.id == "demo").unwrap();
         assert_eq!(spec.source, AgentSource::Registry { version: "1.0.0".into(), update: None });
         assert!(provider::installed(&spec.command));
 
@@ -991,7 +991,7 @@ mod tests {
         assert_eq!((shown[0].installed.as_deref(), shown[0].update), (Some("1.0.104"), true));
 
         write_atomic(&p.cache_file, index.as_bytes()).unwrap();
-        let spec = provider::load(Some(&p.agents_dir)).into_iter().find(|s| s.id == "copilot").unwrap();
+        let spec = provider::load(Some(&p.agents_dir), None).into_iter().find(|s| s.id == "copilot").unwrap();
         assert_eq!(spec.name, "GitHub Copilot");
         assert_eq!(spec.login_hint, "Run `copilot` in a terminal and sign in.");
         assert_eq!(spec.source, AgentSource::Registry { version: "1.0.104".into(), update: None });
@@ -1004,7 +1004,7 @@ mod tests {
         );
 
         remove(&p, "github-copilot-cli").unwrap();
-        let fallback = provider::load(Some(&p.agents_dir)).into_iter().find(|s| s.id == "copilot").unwrap();
+        let fallback = provider::load(Some(&p.agents_dir), None).into_iter().find(|s| s.id == "copilot").unwrap();
         assert_eq!(fallback.source, AgentSource::Builtin);
     }
 }

crates/ide-agent/src/replay_tests.rs

@@ -24,6 +24,7 @@ fn paths(dir: &Path) -> AgentPaths {
         models_file: dir.join("models.json"),
         custom_agents_dir: None,
         home_dir: None,
+        env_secrets: None,
     }
 }
 

crates/ide-agent/src/security.rs

@@ -13,29 +13,23 @@ pub enum PolicyDecision {
     AskUser,
 }
 
-/// Extracts the shell command string from an ACP `session/request_permission` payload
-/// when the request is for executing a command.
+/// The shell command an ACP `session/request_permission` asks to run: only a tool call of kind
+/// `execute`, and only its structured `rawInput` command. A title is free text the agent
+/// writes, so it never names the command.
 pub fn extract_command(params: &Value) -> Option<String> {
     let tool = params.get("toolCall").or_else(|| params.pointer("/subject/toolCall"))?;
+    if tool.get("kind").and_then(Value::as_str) != Some("execute") {
+        return None;
+    }
     let raw_cmd = tool.pointer("/rawInput/command").or_else(|| tool.pointer("/rawInput/cmd"));
-    if let Some(cmd) = raw_cmd.and_then(command_from_value) {
-        return Some(cmd);
-    }
-    let kind = tool.get("kind").and_then(Value::as_str).unwrap_or_default();
-    let name = tool.get("name").and_then(Value::as_str).unwrap_or_default();
-    let title =
-        tool.get("title").and_then(Value::as_str).or_else(|| params.get("title").and_then(Value::as_str))?.trim();
-    if let Some(cmd) = title.strip_prefix("Run ").map(str::trim).filter(|s| !s.is_empty()) {
-        return Some(cmd.to_owned());
-    }
-    if (kind == "execute" || matches!(name, "Bash" | "PowerShell" | "Execute" | "Run" | "terminal"))
-        && !title.is_empty()
-        && title != "Terminal"
-        && title != "Run a command"
-    {
-        return Some(title.to_owned());
-    }
-    None
+    raw_cmd.and_then(command_from_value)
+}
+
+/// Whether allowing the request grants more than running its command, such as network access
+/// for it: the command policy may block such a request but never approves it.
+pub fn widens_access(params: &Value) -> bool {
+    let tool = params.get("toolCall").or_else(|| params.pointer("/subject/toolCall"));
+    tool.and_then(|t| t.pointer("/rawInput/networkApprovalContext")).is_some_and(|c| !c.is_null())
 }
 
 fn command_from_value(val: &Value) -> Option<String> {
@@ -298,6 +292,41 @@ fn split_subcommands(command: &str) -> Vec<&str> {
     out
 }
 
+/// Whether every shell an agent may run `command` in (a POSIX shell, PowerShell, cmd.exe) reads
+/// it as the one command the policy sees. Outside double quotes no separator or redirection may
+/// remain after splitting (cmd.exe takes single quotes literally); `\` may only stand in a
+/// path (it escapes only in POSIX shells); no `^` may escape a quote (cmd.exe); no `%` (cmd.exe
+/// expands it before parsing); no carriage return; no typographic quotes (PowerShell ends
+/// strings at them).
+fn reads_alike_in_every_shell(command: &str) -> bool {
+    let chars: Vec<char> = command.chars().collect();
+    let mut in_double = false;
+    for (i, &c) in chars.iter().enumerate() {
+        let next = chars.get(i + 1).copied();
+        match c {
+            '"' => in_double = !in_double,
+            '\\' if !next.is_none_or(|n| n.is_ascii_alphanumeric() || matches!(n, '\\' | '.' | '_' | '-')) => {
+                return false;
+            }
+            '^' if matches!(next, Some('"' | '\'' | '\n' | '\r')) => return false,
+            '%' | '\r' | '\u{2018}'..='\u{201f}' => return false,
+            ';' | '&' | '|' | '<' | '>' | '\n' if !in_double => return false,
+            _ => {}
+        }
+    }
+    true
+}
+
+/// A command as blocked patterns are compared with it: lower case, single spaces, and the
+/// program without its folder or `.exe` (`/bin/rm` and `RM.EXE` are `rm`).
+fn normalized_for_blocking(command: &str) -> String {
+    let mut words = command.split_whitespace().map(str::to_lowercase);
+    let Some(program) = words.next() else { return String::new() };
+    let program = program.rsplit(['/', '\\']).next().unwrap_or(&program);
+    let program = program.strip_suffix(".exe").unwrap_or(program);
+    std::iter::once(program.to_owned()).chain(words).collect::<Vec<_>>().join(" ")
+}
+
 /// Evaluates `command` against `settings`:
 /// 1. Blacklist takes precedence: if the full command or any sub-command matches a
 ///    `blocked_commands` entry, returns [`PolicyDecision::Blocked`].
@@ -312,12 +341,18 @@ pub fn evaluate_command(command: &str, settings: &AgentSecuritySettings) -> Poli
     }
     let subcommands = split_subcommands(cmd);
 
+    let normalized: Vec<String> =
+        std::iter::once(cmd).chain(subcommands.iter().copied()).map(normalized_for_blocking).collect();
     for pat in &settings.blocked_commands {
         let pat = pat.trim();
         if pat.is_empty() {
             continue;
         }
-        if matches_command(pat, cmd) || subcommands.iter().any(|sub| matches_command(pat, sub)) {
+        let normalized_pat = normalized_for_blocking(pat);
+        if matches_command(pat, cmd)
+            || subcommands.iter().any(|sub| matches_command(pat, sub))
+            || normalized.iter().any(|c| matches_command(&normalized_pat, c))
+        {
             return PolicyDecision::Blocked(pat.to_owned());
         }
     }
@@ -328,7 +363,7 @@ pub fn evaluate_command(command: &str, settings: &AgentSecuritySettings) -> Poli
 
     let all_allowed = subcommands.iter().all(|sub| {
         let s = sub.trim();
-        if s.is_empty() || has_unsafe_shell_syntax(s) {
+        if s.is_empty() || has_unsafe_shell_syntax(s) || !reads_alike_in_every_shell(s) {
             return false;
         }
         settings.allowed_commands.iter().any(|entry| matches_allow_entry(entry, s))
@@ -455,6 +490,58 @@ mod tests {
         assert_eq!(evaluate_command("git status && rm -rf /", &settings), PolicyDecision::Blocked("rm -rf *".into()));
     }
 
+    /// The command may run in PowerShell or cmd.exe as well as a POSIX shell: what any of them
+    /// would split or expand differently from the policy's reading is never auto-approved.
+    #[test]
+    fn what_another_shell_reads_as_two_commands_is_not_auto_approved() {
+        let settings = AgentSecuritySettings {
+            allowed_commands: vec!["git status".into(), "git commit".into()],
+            blocked_commands: vec![],
+        };
+        for cmd in [
+            // `\` escapes only in POSIX shells.
+            "git status \\; calc.exe",
+            "git status \\& calc.exe",
+            "git status \\| calc.exe",
+            "git status \\\\\\; calc.exe",
+            "git status \"\\\" ; calc.exe ; \\\"\"",
+            // cmd.exe: single quotes don't quote, `^` escapes a quote, `%` expands first.
+            "git status '&' calc.exe",
+            "git status ';' calc.exe",
+            "git status '>' out.txt",
+            "git status ^\" & calc.exe ^\"",
+            "git status %COMSPEC%",
+            // PowerShell also closes a string at a typographic quote.
+            "git status \"a \u{201d} ; calc.exe ; \u{201c} b\"",
+            "git status \u{2018}x\u{2019}",
+            // A carriage return ends the command line too.
+            "git status\r calc.exe",
+        ] {
+            assert_eq!(evaluate_command(cmd, &settings), PolicyDecision::AskUser, "{cmd:?}");
+        }
+        // Text every shell reads alike stays approvable.
+        for cmd in [
+            "git status -s",
+            "git status && git status",
+            "git commit -m \"fix <bug> & (issue); done\"",
+            "git status src\\main.rs C:\\work\\repo",
+            "git status HEAD^",
+        ] {
+            assert_eq!(evaluate_command(cmd, &settings), PolicyDecision::Allowed, "{cmd:?}");
+        }
+    }
+
+    #[test]
+    fn blocked_patterns_ignore_case_spacing_and_the_programs_folder() {
+        let settings = AgentSecuritySettings::default();
+        for cmd in
+            ["rm  -rf /", "RM -RF /", "/bin/rm -rf /", "Rm -Rf  /tmp/x", "C:\\Windows\\System32\\shutdown.exe /s"]
+        {
+            assert!(matches!(evaluate_command(cmd, &settings), PolicyDecision::Blocked(_)), "{cmd:?}");
+        }
+        assert_eq!(evaluate_command("git status", &settings), PolicyDecision::AskUser);
+    }
+
     #[test]
     fn extracts_command_from_v1_v2_and_codex_payloads() {
         let claude = json!({
@@ -484,4 +571,30 @@ mod tests {
         });
         assert_eq!(extract_command(&write), None);
     }
+
+    /// Only a tool call of kind `execute` runs a command, and its command is in `rawInput`:
+    /// a title says what the agent wants it to say.
+    #[test]
+    fn a_request_is_a_command_only_by_its_kind_and_input() {
+        let escalation = json!({ "sessionId": "t", "toolCall": {
+            "toolCallId": "i1", "title": "Run git status", "kind": "other", "status": "pending",
+            "rawInput": { "fileSystem": { "write": ["C:\\"] }, "network": { "enabled": true } } },
+            "options": [ { "optionId": "turn", "name": "Allow for this turn", "kind": "allow_once" },
+                         { "optionId": "decline", "name": "Decline", "kind": "reject_once" } ] });
+        assert_eq!(extract_command(&escalation), None);
+        let titled_only = json!({ "toolCall": { "title": "Run git status", "kind": "execute" } });
+        assert_eq!(extract_command(&titled_only), None);
+        let named_only = json!({ "toolCall": { "title": "git status", "name": "Bash" } });
+        assert_eq!(extract_command(&named_only), None);
+        let mislabelled = json!({ "toolCall": { "title": "Run git status", "kind": "edit",
+            "rawInput": { "command": "git status" } } });
+        assert_eq!(extract_command(&mislabelled), None);
+        let network = json!({ "toolCall": { "title": "Allow network access to example.com", "kind": "execute",
+            "rawInput": { "command": "curl https://example.com", "networkApprovalContext": { "host": "example.com" } } } });
+        assert_eq!(extract_command(&network).as_deref(), Some("curl https://example.com"));
+        assert!(widens_access(&network));
+        let plain = json!({ "toolCall": { "title": "Run git status", "kind": "execute",
+            "rawInput": { "command": "git status" } } });
+        assert!(!widens_access(&plain));
+    }
 }

crates/ide-agent/src/tests.rs

@@ -264,6 +264,23 @@ impl Handler for FakeAgent {
                     self.say(&session, &format!("late chose {chosen}"));
                     return Ok(json!({"stopReason": "end_turn"}));
                 }
+                if text == "escalate" {
+                    // A request for wider access, titled with text the model wrote.
+                    let peer = self.latest();
+                    let answer: Value = tokio::runtime::Handle::current()
+                        .block_on(peer.request(
+                            "session/request_permission",
+                            json!({"sessionId": session, "toolCall": {"toolCallId": "e1", "title": "Run cargo test",
+                                "kind": "other", "rawInput": {"network": {"enabled": true}}},
+                                "options": [{"optionId": "yes", "name": "Allow for this turn", "kind": "allow_once"},
+                                            {"optionId": "no", "name": "Decline", "kind": "reject_once"}]}),
+                            None,
+                        ))
+                        .unwrap();
+                    let chosen = answer.pointer("/outcome/optionId").and_then(Value::as_str).unwrap_or("none");
+                    self.say(&session, &format!("escalation chose {chosen}"));
+                    return Ok(json!({"stopReason": "end_turn"}));
+                }
                 if text == "ask" {
                     let peer = self.latest();
                     let answer: Value = tokio::runtime::Handle::current()
@@ -344,7 +361,8 @@ impl Handler for FakeAgent {
                 let answer: Value = tokio::runtime::Handle::current()
                     .block_on(peer.request(
                         "session/request_permission",
-                        json!({"sessionId": session, "toolCall": {"toolCallId": "t1", "title": "Run cargo test"},
+                        json!({"sessionId": session, "toolCall": {"toolCallId": "t1", "title": "Run cargo test",
+                            "kind": "execute", "rawInput": {"command": "cargo test"}},
                             "options": [{"optionId": "yes", "name": "Allow", "kind": "allow_once"},
                                         {"optionId": "no", "name": "Reject", "kind": "reject_once"}]}),
                         None,
@@ -366,7 +384,8 @@ fn manager(dir: &Path, agent: Arc<FakeAgent>) -> AgentManager {
 fn manager_at(dir: &Path, models_file: &Path, agent: Arc<FakeAgent>) -> AgentManager {
     // These tests speak to FakeAgent, never an installed CLI, including after a provider reload.
     let agents = dir.join("agents");
-    provider::set_builtin_command(&agents, "claude", Some(&dir.join("missing-claude").to_string_lossy())).unwrap();
+    provider::set_builtin_command(&agents, None, "claude", Some(&dir.join("missing-claude").to_string_lossy()))
+        .unwrap();
     let connector: Connector = Arc::new(move |_spec, _cwd, client, _stderr| {
         let (a, b) = duplex(1 << 20);
         let (ar, aw) = tokio::io::split(a);
@@ -385,6 +404,7 @@ fn manager_at(dir: &Path, models_file: &Path, agent: Arc<FakeAgent>) -> AgentMan
             // The project is the boundary of the skill walk: nothing above it (such as the
             // user's profile, when temp lives under it) leaks into the test.
             home_dir: Some(dir.to_path_buf()),
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
         connector,
@@ -1410,6 +1430,7 @@ async fn real_claude_task_in_a_worktree() {
             models_file: tmp.path().join("models.json"),
             custom_agents_dir: None,
             home_dir: None,
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
     );
@@ -2243,6 +2264,7 @@ async fn reload_providers_updates_registry_install_clears_stale_probes_and_notif
             models_file: tmp.path().join("models.json"),
             custom_agents_dir: Some(agents_dir.clone()),
             home_dir: None,
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
         connector,
@@ -2553,6 +2575,7 @@ async fn delete_running_agent(no_load: bool) {
             models_file: root.join("models.json"),
             custom_agents_dir: None,
             home_dir: None,
+            env_secrets: None,
         },
         tokio::runtime::Handle::current(),
         connector,
@@ -3187,3 +3210,43 @@ async fn security_policy_auto_approves_whitelist_and_rejects_blacklist() {
         "{blocked_entries:?}"
     );
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn security_policy_never_auto_approves_a_request_that_only_reads_like_a_command() {
+    use ide_core::settings::AgentSecuritySettings;
+
+    let tmp = tempfile::tempdir().unwrap();
+    let agent = Arc::new(FakeAgent::default());
+    let mgr = manager(tmp.path(), agent);
+    mgr.set_security_hook(Arc::new(|| AgentSecuritySettings {
+        allowed_commands: vec!["cargo test".into()],
+        blocked_commands: vec![],
+    }));
+    let task = mgr
+        .create(NewAgentTask {
+            project_root: None,
+            prompt: text("escalate"),
+            provider: "claude".into(),
+            config: vec![],
+            isolation: Isolation::Local,
+            base: None,
+        })
+        .await
+        .unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::NeedsInput).await;
+    let entries = mgr.entries(&task.id, None).unwrap();
+    let pending = entries
+        .iter()
+        .find_map(|e| match e {
+            AgentEntry::Permission { id, chosen: None, .. } => Some(*id),
+            _ => None,
+        })
+        .unwrap_or_else(|| panic!("the request was answered without the user: {entries:?}"));
+    mgr.respond(&task.id, pending, Some("no".into())).unwrap();
+    wait_for(&mgr, &task.id, AgentStatus::Ready).await;
+    let entries = mgr.entries(&task.id, None).unwrap();
+    assert!(
+        entries.iter().any(|e| matches!(e, AgentEntry::Agent { text } if text == "escalation chose no")),
+        "{entries:?}"
+    );
+}

crates/ide-agent/src/timeline.rs

@@ -438,6 +438,7 @@ mod tests {
         t.push(AgentEntry::Permission {
             id: 1,
             title: "Run?".into(),
+            command: None,
             options: vec![],
             questions: vec![],
             chosen: None,

crates/ide-agent/src/worktree.rs

@@ -358,6 +358,38 @@ impl TaskBase {
     }
 }
 
+/// One side of an Accept (the task's worktree or the checkout): where its files really are, and
+/// git's own folders for it.
+struct Confined {
+    root: PathBuf,
+    metadata: Vec<PathBuf>,
+}
+
+impl Confined {
+    fn new(root: &Path, repo: Option<&Repo>) -> IdeResult<Self> {
+        let metadata = match repo {
+            Some(repo) => repo.metadata_dirs()?.iter().map(|d| ide_core::real_path::resolve_real(d)).collect(),
+            None => Vec::new(),
+        };
+        Ok(Self { root: dunce::canonicalize(root)?, metadata })
+    }
+
+    /// Whether `rel` may be read or written here: it doesn't name git's metadata under any
+    /// spelling (case, trailing dots or spaces, stream suffixes, short names), stays in the tree
+    /// once links are followed, and isn't a link itself.
+    fn allows(&self, rel: &str) -> bool {
+        use ide_core::real_path::{names_git_dir, reaches_git_dir, resolve_real};
+        let path = self.root.join(rel);
+        if names_git_dir(Path::new(rel)) || path.symlink_metadata().is_ok_and(|m| m.file_type().is_symlink()) {
+            return false;
+        }
+        let real = resolve_real(&path);
+        real.starts_with(&self.root)
+            && !reaches_git_dir(&self.root, &real)
+            && !self.metadata.iter().any(|dir| real.starts_with(dir))
+    }
+}
+
 /// Copies the task's `changes` (against `base`) from the worktree `cwd` into the
 /// local checkout `root`, uncommitted: the user reviews and commits them with the
 /// VCS tools. Files the checkout changed itself are left alone and reported, so
@@ -370,7 +402,13 @@ pub(crate) fn accept(
 ) -> IdeResult<crate::AgentAcceptOutcome> {
     let repo = repo_at(cwd)?;
     // Change paths are repository-relative, and the task's project may be a folder inside it.
-    let local_root = discover(root)?.map_or_else(|| root.to_path_buf(), |r| r.root().to_path_buf());
+    let local = discover(root)?;
+    let local_root = local.as_ref().map_or_else(|| root.to_path_buf(), |r| r.root().to_path_buf());
+    // Paths come from what the agent left in its worktree: neither side may lead into git's own
+    // files or out through a link.
+    let task_side = Confined::new(repo.root(), Some(&repo))?;
+    let checkout_side = Confined::new(&local_root, local.as_ref())?;
+    let copyable = |rel: &str| task_side.allows(rel) && checkout_side.allows(rel);
     let renamed_from: BTreeMap<String, String> =
         repo.diff_with_worktree(base)?.into_iter().filter_map(|f| Some((f.path, f.old_path?))).collect();
     // Brings one path of the checkout to the task's version, unless the checkout changed it itself.
@@ -411,13 +449,25 @@ pub(crate) fn accept(
         path: path.to_owned(),
         reason: "the checkout has changes of its own to it; accept it by hand".to_owned(),
     };
+    let refuse = |path: &str| crate::AgentAcceptSkipped {
+        path: path.to_owned(),
+        reason: "it leads into git's own files or through a link, so it is not copied".to_owned(),
+    };
     for change in changes {
+        let old = renamed_from.get(&change.rel_path);
+        if !copyable(&change.rel_path) {
+            skipped.push(refuse(&change.rel_path));
+            continue;
+        }
+        if let Some(old) = old.filter(|old| !copyable(old)) {
+            skipped.push(refuse(old));
+            continue;
+        }
         // A case-only rename (`a.txt` → `A.txt`). Where the disk resolves both
         // spellings to one file it is renamed in place and `apply` then refreshes
         // the content. On a case-sensitive disk the two names are different files:
         // the old one's unchanged-ness (it is the file the checkout had) decides —
         // then the task's version lands at the new name and the old one goes.
-        let old = renamed_from.get(&change.rel_path);
         let case_only =
             old.is_some_and(|o| o != &change.rel_path && o.to_lowercase() == change.rel_path.to_lowercase());
         if case_only {
@@ -910,6 +960,103 @@ mod tests {
         assert_eq!(names, ["A.txt"]);
     }
 
+    #[cfg(windows)]
+    #[test]
+    fn accept_does_not_write_into_the_checkouts_git_folder_through_its_short_name() {
+        let (_tmp, repo, created) = accept_repo();
+        if !repo.join("GIT~1").join("HEAD").is_file() {
+            eprintln!("8.3 short names are disabled on this volume; nothing to check");
+            return;
+        }
+        // Written in the worktree under the name the checkout's `.git` folder also has.
+        let wt = &created.path;
+        std::fs::rename(wt.join(".git"), wt.join("gitfile")).unwrap();
+        std::fs::create_dir_all(wt.join("GIT~1").join("hooks")).unwrap();
+        std::fs::write(wt.join("GIT~1").join("hooks").join("pre-commit"), "#!/bin/sh\nexit 0\n").unwrap();
+        std::fs::rename(wt.join("gitfile"), wt.join(".git")).unwrap();
+        std::fs::write(wt.join("a.txt"), "one\nTWO\n").unwrap();
+
+        let changes = listed(wt, &created.base_commit);
+        assert!(changes.iter().any(|c| c.rel_path == "GIT~1/hooks/pre-commit"), "control: git lists it");
+        let outcome = accept(&repo, wt, &created.base_commit, &changes).unwrap();
+        assert!(!repo.join(".git").join("hooks").join("pre-commit").exists(), "{outcome:?}");
+        assert_eq!(outcome.accepted, ["a.txt"]);
+        assert_eq!(outcome.skipped.iter().map(|s| s.path.as_str()).collect::<Vec<_>>(), ["GIT~1/hooks/pre-commit"]);
+    }
+
+    #[test]
+    fn accept_refuses_paths_that_lead_into_git_metadata_under_any_spelling() {
+        let (tmp, repo, _created) = accept_repo();
+        let checkout = Confined::new(&repo, Repo::discover(&repo).unwrap().as_ref()).unwrap();
+        for rel in [
+            ".git/hooks/pre-commit",
+            ".GIT/hooks/pre-commit",
+            ".git./hooks/pre-commit",
+            ".git /hooks/pre-commit",
+            ".git::$INDEX_ALLOCATION/hooks/pre-commit",
+            "sub/.git/config",
+            "../outside.txt",
+        ] {
+            assert!(!checkout.allows(rel), "{rel}");
+        }
+        assert!(checkout.allows("src/new.txt"));
+        assert!(checkout.allows(".github/workflows/ci.yml"));
+
+        // git's folder under another name inside the tree (`--separate-git-dir`).
+        let separate = tmp.path().join("separate");
+        std::fs::create_dir(&separate).unwrap();
+        git(&separate, &["init", "-q", "--separate-git-dir", "meta", "-b", "main"]);
+        let side = Confined::new(&separate, Repo::discover(&separate).unwrap().as_ref()).unwrap();
+        assert!(!side.allows("meta/hooks/pre-commit"));
+        assert!(side.allows("metadata.txt"));
+    }
+
+    /// A link the task left in its worktree, or a linked folder in the checkout: neither is followed.
+    #[test]
+    fn accept_does_not_follow_links_on_either_side() {
+        let (tmp, repo, created) = accept_repo();
+        let outside = tmp.path().join("outside");
+        std::fs::create_dir(&outside).unwrap();
+        std::fs::write(outside.join("secret.txt"), "secret\n").unwrap();
+        // A folder link in the checkout (a junction on Windows, which needs no privilege).
+        #[cfg(unix)]
+        std::os::unix::fs::symlink(&outside, repo.join("linked")).unwrap();
+        #[cfg(windows)]
+        assert!(
+            std::process::Command::new("cmd")
+                .args(["/c", "mklink", "/J"])
+                .arg(repo.join("linked"))
+                .arg(&outside)
+                .output()
+                .unwrap()
+                .status
+                .success()
+        );
+        std::fs::create_dir(created.path.join("linked")).unwrap();
+        std::fs::write(created.path.join("linked/new.txt"), "x\n").unwrap();
+        std::fs::write(created.path.join("a.txt"), "one\nTWO\n").unwrap();
+        // A file link in the worktree, where the platform lets this user create one.
+        #[cfg(unix)]
+        let file_link = std::os::unix::fs::symlink(outside.join("secret.txt"), created.path.join("copied.txt"));
+        #[cfg(windows)]
+        let file_link = std::os::windows::fs::symlink_file(outside.join("secret.txt"), created.path.join("copied.txt"));
+        if let Err(e) = &file_link {
+            eprintln!("no file link ({e}); checking the folder link only");
+        }
+
+        let changes: Vec<_> = listed(&created.path, &created.base_commit);
+        let outcome = accept(&repo, &created.path, &created.base_commit, &changes).unwrap();
+        assert!(!outside.join("new.txt").exists(), "{outcome:?}");
+        assert!(!repo.join("copied.txt").exists(), "{outcome:?}");
+        assert!(outcome.accepted.contains(&"a.txt".to_owned()));
+        let refused: Vec<_> = outcome.skipped.iter().map(|s| s.path.as_str()).collect();
+        if file_link.is_ok() {
+            assert_eq!(refused, ["copied.txt", "linked/new.txt"]);
+        } else {
+            assert_eq!(refused, ["linked/new.txt"]);
+        }
+    }
+
     #[test]
     fn accept_copies_new_modified_and_deleted_files_into_the_checkout() {
         let (_tmp, repo, created) = accept_repo();

crates/ide-build/src/maven.rs

@@ -16,6 +16,7 @@ use std::io::Read;
 use std::path::{Path, PathBuf};
 use std::sync::{Mutex, OnceLock};
 
+pub mod completion;
 pub mod sources;
 
 /// Lets the IDE's own Maven runs (Reload, Build) use what the local repository already
@@ -299,7 +300,7 @@ fn read_plugin(e: &Element) -> Option<RawPlugin> {
     })
 }
 
-fn read_properties(e: Option<&Element>) -> Vec<(String, String)> {
+pub(crate) fn read_properties(e: Option<&Element>) -> Vec<(String, String)> {
     e.map(|p| p.children.iter().map(|c| (c.name.clone(), c.text.trim().to_owned())).collect()).unwrap_or_default()
 }
 
@@ -1679,6 +1680,15 @@ pub enum PomGotoKind {
     ManagedDependency,
     /// A `<pluginManagement>` entry providing the plugin's version.
     ManagedPlugin,
+    /// The POM of the artifact itself: a project module's, else the local repository's.
+    ArtifactPom,
+}
+
+/// A Maven project of the workspace, for going to a dependency on it.
+pub struct ModulePom {
+    pub group_id: String,
+    pub artifact_id: String,
+    pub pom: PathBuf,
 }
 
 /// Byte offset of `pos` (0-based line / UTF-16 column), clamped to `text`.
@@ -1729,7 +1739,7 @@ fn property_ref_at(text: &str, at: usize) -> Option<(&str, usize, usize)> {
 }
 
 /// The elements containing `at`, from the root down to the innermost one.
-fn element_path(root: &Element, at: usize) -> Vec<&Element> {
+pub(crate) fn element_path(root: &Element, at: usize) -> Vec<&Element> {
     let mut path = vec![root];
     loop {
         let Some(next) = path.last().unwrap().children.iter().find(|c| c.start <= at && at < c.end) else {
@@ -1758,6 +1768,20 @@ fn coordinates(e: &Element, props: &HashMap<String, String>) -> Option<(String,
 /// the local repository when it is not in the project). `None` when there is no
 /// resolvable declaration here.
 pub fn goto_declaration(text: &str, path: &Path, pos: Pos, local_repo: Option<PathBuf>) -> Option<PomGoto> {
+    goto_declaration_in(text, path, pos, local_repo, Vec::new)
+}
+
+/// [`goto_declaration`], where a `<parent>` and a dependency or plugin whose version no
+/// management entry provides (or a management entry itself) go to the artifact's own
+/// POM: the project module among `modules` with its coordinates, else the local
+/// repository's POM of its version.
+pub fn goto_declaration_in(
+    text: &str,
+    path: &Path,
+    pos: Pos,
+    local_repo: Option<PathBuf>,
+    modules: impl FnOnce() -> Vec<ModulePom>,
+) -> Option<PomGoto> {
     let root = xml::parse(text).filter(|e| e.name == "project")?;
     let at = offset_at(text, pos);
     if let Some((name, _, _)) = property_ref_at(text, at)
@@ -1768,15 +1792,56 @@ pub fn goto_declaration(text: &str, path: &Path, pos: Pos, local_repo: Option<Pa
     // A `<dependency>` / `<plugin>` in a declaration position: its version may come
     // from a management entry of this POM or an ancestor's.
     let elements = element_path(&root, at);
-    let e = elements.iter().rev().find(|e| e.name == "dependency" || e.name == "plugin")?;
-    if elements.iter().any(|a| a.name == "dependencyManagement" || a.name == "pluginManagement") {
-        return None; // Management entries are declarations; there is nothing to go to.
+    if elements.get(1).is_some_and(|e| e.name == "parent") {
+        let chain = parent_chain(path, text, local_repo);
+        let (pom, parent_text) = chain.get(1)?;
+        let label = elements[1].text_of("artifactId").unwrap_or_default();
+        return Some(pom_goto(pom.clone(), parent_text, label));
     }
-    let kind = match e.name.as_str() {
-        "dependency" => PomGotoKind::ManagedDependency,
-        _ => PomGotoKind::ManagedPlugin,
-    };
-    managed_target(text, path, e, kind, local_repo)
+    let e = elements.iter().rev().find(|e| e.name == "dependency" || e.name == "plugin")?;
+    // A management entry declares the version: it goes to the artifact (a BOM import, say).
+    if !elements.iter().any(|a| a.name == "dependencyManagement" || a.name == "pluginManagement") {
+        let kind = match e.name.as_str() {
+            "dependency" => PomGotoKind::ManagedDependency,
+            _ => PomGotoKind::ManagedPlugin,
+        };
+        if let Some(found) = managed_target(text, path, e, kind, local_repo.clone()) {
+            return Some(found);
+        }
+    }
+    artifact_target(text, path, e, local_repo, modules)
+}
+
+/// The artifact's own POM for a dependency or plugin element `e`.
+fn artifact_target(
+    text: &str,
+    path: &Path,
+    e: &Element,
+    local_repo: Option<PathBuf>,
+    modules: impl FnOnce() -> Vec<ModulePom>,
+) -> Option<PomGoto> {
+    let mut resolver = Resolver::new(local_repo.clone(), &[]);
+    let chain = parent_chain(path, text, local_repo);
+    let props = properties_at(&mut resolver, &chain, 0);
+    let (group, artifact) = coordinates(e, &props)?;
+    let label = format!("{group}:{artifact}");
+    if let Some(module) = modules().into_iter().find(|m| m.group_id == group && m.artifact_id == artifact) {
+        let module_text = xml::read_text(&module.pom)?;
+        return Some(pom_goto(module.pom, &module_text, label));
+    }
+    let version = interpolate(&e.text_of("version")?, &props);
+    let pom = resolver.repo_pom(&group, &artifact, &version)?;
+    let pom_text = xml::read_text(&pom)?;
+    Some(pom_goto(pom, &pom_text, label))
+}
+
+/// The POM at `path` as a target, at its `<artifactId>`.
+fn pom_goto(path: PathBuf, text: &str, label: String) -> PomGoto {
+    let range = xml::parse(text)
+        .filter(|e| e.name == "project")
+        .and_then(|root| root.child("artifactId").map(|a| range_of(text, a)))
+        .unwrap_or_default();
+    PomGoto { path, range, kind: PomGotoKind::ArtifactPom, label }
 }
 
 /// The parent POMs of the POM in `text` at `path`, child-first (its `<parent>` refs,
@@ -3086,9 +3151,9 @@ mod tests {
         let text = std::fs::read_to_string(&path).unwrap();
         // The property is declared nowhere along the chain.
         assert_eq!(goto_declaration(&text, &path, at(&text, "${missing.key}"), None), None);
-        // The dependency names its own version: it is the declaration.
+        // The dependency names its own version and no local repository has its POM.
         assert_eq!(goto_declaration(&text, &path, at(&text, "<artifactId>other-lib"), None), None);
-        // A management entry is a declaration itself, not a reference.
+        // A management entry declares the version; its artifact's POM is not at hand either.
         let parent_path = tmp.path().join("pom.xml");
         let parent_text = std::fs::read_to_string(&parent_path).unwrap();
         assert_eq!(
@@ -3100,6 +3165,72 @@ mod tests {
         assert_eq!(goto_declaration("<project></project>", &path, Pos::new(0, 3), None), None);
     }
 
+    #[test]
+    fn artifacts_go_to_their_own_pom_in_the_project_or_the_local_repository() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = tmp.path().join("repo");
+        let bom_dir = repo.join("com/alibaba/cloud/spring-cloud-alibaba-dependencies/2.2.6.RELEASE");
+        std::fs::create_dir_all(&bom_dir).unwrap();
+        let bom = "<project>\n  <groupId>com.alibaba.cloud</groupId>\n  <artifactId>spring-cloud-alibaba-dependencies</artifactId>\n</project>";
+        std::fs::write(bom_dir.join("spring-cloud-alibaba-dependencies-2.2.6.RELEASE.pom"), bom).unwrap();
+        let parent = format!(
+            r#"{PARENT_HEADER}<properties><alibaba.version>2.2.6.RELEASE</alibaba.version></properties>
+<dependencyManagement>
+  <dependencies>
+    <dependency>
+      <groupId>com.alibaba.cloud</groupId>
+      <artifactId>spring-cloud-alibaba-dependencies</artifactId>
+      <version>${{alibaba.version}}</version>
+      <type>pom</type>
+      <scope>import</scope>
+    </dependency>
+  </dependencies>
+</dependencyManagement>
+</project>"#
+        );
+        let child = format!(
+            r#"{CHILD_HEADER}<dependencies>
+  <dependency>
+    <groupId>com.example</groupId>
+    <artifactId>core</artifactId>
+    <version>1.0</version>
+  </dependency>
+</dependencies>
+</project>"#
+        );
+        write_parent_child(tmp.path(), &parent, &child);
+        let core = tmp.path().join("core/pom.xml");
+        std::fs::create_dir_all(core.parent().unwrap()).unwrap();
+        std::fs::write(
+            &core,
+            "<project>\n  <groupId>com.example</groupId>\n  <artifactId>core</artifactId>\n</project>",
+        )
+        .unwrap();
+        let modules =
+            || vec![ModulePom { group_id: "com.example".into(), artifact_id: "core".into(), pom: core.clone() }];
+
+        // A BOM import in <dependencyManagement> opens the BOM from the local repository.
+        let parent_path = tmp.path().join("pom.xml");
+        let parent_text = std::fs::read_to_string(&parent_path).unwrap();
+        let at_bom = at(&parent_text, "spring-cloud-alibaba-dependencies<");
+        let goto = goto_declaration_in(&parent_text, &parent_path, at_bom, Some(repo.clone()), modules).unwrap();
+        assert_eq!(goto.path, bom_dir.join("spring-cloud-alibaba-dependencies-2.2.6.RELEASE.pom"));
+        assert_eq!(goto.kind, PomGotoKind::ArtifactPom);
+        assert_eq!(goto.range.start, pos_at(bom, bom.find("<artifactId>").unwrap()));
+
+        // A dependency on a project module opens the module's POM.
+        let path = tmp.path().join("app/pom.xml");
+        let text = std::fs::read_to_string(&path).unwrap();
+        let goto =
+            goto_declaration_in(&text, &path, at(&text, "core</artifactId>"), Some(repo.clone()), modules).unwrap();
+        assert_eq!((goto.path.as_path(), goto.label.as_str()), (core.as_path(), "com.example:core"));
+
+        // The <parent> section opens the parent POM.
+        let goto = goto_declaration_in(&text, &path, at(&text, "parent</artifactId>"), Some(repo), modules).unwrap();
+        assert_eq!(goto.path, canon(&parent_path));
+        assert_eq!(goto.kind, PomGotoKind::ArtifactPom);
+    }
+
     #[test]
     fn a_property_reference_after_non_ascii_text_is_still_found() {
         let text = format!(

crates/ide-build/src/maven/completion.rs

@@ -0,0 +1,677 @@
+//! Completion of Maven coordinates in a POM: inside a `<dependency>`, the
+//! `<groupId>`, `<artifactId>` and `<version>` values are completed from the
+//! local repository layout (`<repo>/<group path>/<artifactId>/<version>/…`).
+//! The Maven Central search endpoint tops the lists up remotely; the host op
+//! fetches those (cached) and merges them behind the local ones, so this side
+//! stays pure text and directory logic and tests build their own repositories.
+
+use super::xml::{self, Element};
+use super::{element_path, interpolate, read_properties};
+use serde::{Deserialize, Serialize};
+use specta::Type;
+use std::cmp::Ordering;
+use std::collections::HashMap;
+use std::path::{Path, PathBuf};
+
+/// The coordinate element a POM completion fills.
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub enum PomCompletionKind {
+    /// The dependency's `<groupId>`.
+    GroupId,
+    /// The dependency's `<artifactId>`.
+    ArtifactId,
+    /// The dependency's `<version>`.
+    Version,
+}
+
+/// One suggestion: the coordinate as inserted, and an optional note shown in
+/// the lookup (the owning group of an artifactId, its newest installed version).
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct PomCompletionOption {
+    /// The text the completion inserts (`org.example.lib`, `example-lib`, `1.2.0`).
+    pub label: String,
+    pub detail: Option<String>,
+}
+
+/// The completion offered at a caret of a POM: the replaced value span (UTF-16
+/// offsets) and the suggestions, local ones first.
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub struct PomCompletion {
+    /// UTF-16 offset where the completed text starts: the value's first character.
+    pub from: u32,
+    /// UTF-16 offset where the replaced value ends: past the caret when the caret
+    /// sits inside an existing value, which is then replaced whole.
+    pub to: u32,
+    /// Which coordinate element the caret is in.
+    pub kind: PomCompletionKind,
+    /// The suggestions, local repository first.
+    pub options: Vec<PomCompletionOption>,
+}
+
+/// Where the caret sits in a `<dependency>` coordinate element: what is being
+/// completed, the typed prefix, and the sibling coordinates the rest need.
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct PomCompletionTarget {
+    /// UTF-16 offset of the value's first character (the caret in an empty value).
+    pub from: u32,
+    /// UTF-16 offset past the value's last character (the caret in an empty value).
+    pub to: u32,
+    /// The value typed so far: the text between `from` and the caret, trimmed.
+    pub typed: String,
+    pub kind: PomCompletionKind,
+    /// The interpolated `<groupId>` sibling, when completing the artifactId and
+    /// the group is written out plain (no unresolved `${property}`).
+    pub group: Option<String>,
+    /// The interpolated `<artifactId>` sibling, when completing the version.
+    pub artifact: Option<String>,
+}
+
+/// A coordinate element's text, with the POM's own `${properties}` replaced;
+/// `None` when the element is missing or a property stays unresolved (the
+/// coordinates behind it are not known without the parent chain, which the
+/// completion does not follow).
+fn coordinate(e: Option<&Element>, props: &HashMap<String, String>) -> Option<String> {
+    let text = interpolate(e?.text.trim(), props);
+    (!text.is_empty() && !text.contains("${")).then_some(text)
+}
+
+fn own_properties(root: &Element) -> HashMap<String, String> {
+    read_properties(root.child("properties")).into_iter().collect()
+}
+
+/// UTF-16 offset -> byte offset, clamped to `text`.
+fn utf16_to_byte(text: &str, offset: u32) -> usize {
+    let mut seen = 0u32;
+    for (byte, c) in text.char_indices() {
+        if seen >= offset {
+            return byte;
+        }
+        seen += c.len_utf16() as u32;
+    }
+    text.len()
+}
+
+/// Byte offset -> UTF-16 offset.
+fn utf16_at(text: &str, byte: usize) -> u32 {
+    text[..byte].encode_utf16().count() as u32
+}
+
+/// Byte offset just past the start tag's `>` of the element at `start`.
+fn start_tag_end(text: &str, start: usize) -> Option<usize> {
+    let bytes = text.as_bytes();
+    let mut i = start.checked_add(1)?;
+    let mut quote = None;
+    while i < bytes.len() {
+        match (quote, bytes[i]) {
+            (Some(q), b) if b == q => quote = None,
+            (Some(_), _) => {}
+            (None, b'"' | b'\'') => quote = Some(bytes[i]),
+            (None, b'>') => return Some(i + 1),
+            _ => {}
+        }
+        i += 1;
+    }
+    None
+}
+
+/// What to complete at the caret (`offset`, UTF-16) of the POM `text`: the
+/// `<groupId>` / `<artifactId>` / `<version>` element of a `<dependency>` the
+/// caret sits in the value of. `None` everywhere else — other elements, carets
+/// in an end tag or a `${property}` reference, dependencies without the
+/// `<groupId>` (and, for versions, the `<artifactId>`) their completions need.
+pub fn completion_target(text: &str, offset: u32) -> Option<PomCompletionTarget> {
+    let root = xml::parse(text).filter(|e| e.name == "project")?;
+    let at = utf16_to_byte(text, offset);
+    // A caret at the very end of the input sits in the element still being
+    // typed, whose range reaches to the input's end; step back one character
+    // so `element_path` sees it (the caret's own offset stays `at`).
+    let probe = if at == text.len() && at > 0 {
+        let mut p = at - 1;
+        while p > 0 && !text.is_char_boundary(p) {
+            p -= 1;
+        }
+        p
+    } else {
+        at
+    };
+    let elements = element_path(&root, probe);
+    let e = *elements.last()?;
+    let parent = elements.get(elements.len().checked_sub(2)?)?;
+    let kind = match e.name.as_str() {
+        "groupId" => PomCompletionKind::GroupId,
+        "artifactId" => PomCompletionKind::ArtifactId,
+        "version" => PomCompletionKind::Version,
+        _ => return None,
+    };
+    if parent.name != "dependency" || at > e.inner_end {
+        return None;
+    }
+    let inner_start = start_tag_end(text, e.start)?;
+    let value = &text[inner_start..e.inner_end.max(inner_start)];
+    if value.contains("${") {
+        return None; // Property references are goto-declaration territory, not completion.
+    }
+    let lead = value.len() - value.trim_start().len();
+    let trail = value.len() - value.trim_end().len();
+    let (mut from, mut to) = (inner_start + lead, e.inner_end.max(inner_start) - trail);
+    if from > to {
+        // A value of whitespace only: complete at the caret.
+        from = at.min(to);
+        to = to.max(from);
+    }
+    from = from.min(at);
+    to = to.max(from);
+    let props = own_properties(&root);
+    let group = (kind != PomCompletionKind::GroupId).then(|| coordinate(parent.child("groupId"), &props)).flatten();
+    let artifact =
+        (kind == PomCompletionKind::Version).then(|| coordinate(parent.child("artifactId"), &props)).flatten();
+    let typed = text[from..at].trim().to_owned();
+    Some(PomCompletionTarget { from: utf16_at(text, from), to: utf16_at(text, to), typed, kind, group, artifact })
+}
+
+/// The suggestions the local repository at `repo` offers for `target`: group
+/// ids installed under it, the artifacts of the target's group, or the versions
+/// of the target's artifact. Every scan is bounded (see `SCAN_BUDGET`) and
+/// reads only directory listings of `repo` — nothing outside it, no jar
+/// contents.
+pub fn local_options(repo: &Path, target: &PomCompletionTarget) -> Vec<PomCompletionOption> {
+    let mut budget = SCAN_BUDGET;
+    match target.kind {
+        // `org.spr` completes the `spr` part under `org/`, `org.` the next
+        // segment under `org/`; every typed segment is validated so POM text
+        // cannot walk out of the repository.
+        PomCompletionKind::GroupId => {
+            let segments: Vec<&str> = target.typed.split('.').collect();
+            let (partial, base) = segments.split_last().unwrap_or((&"", &[]));
+            if base.iter().all(|s| segment(s)) {
+                let dir = base.iter().fold(repo.to_path_buf(), |p, s| p.join(s));
+                scan_groups(&dir, &base.join("."), partial, &mut budget)
+            } else {
+                Vec::new()
+            }
+        }
+        PomCompletionKind::ArtifactId => target
+            .group
+            .as_deref()
+            .and_then(|g| repo_dir(repo, &[g]))
+            .map_or_else(Vec::new, |dir| scan_artifacts(&dir, &target.typed, &mut budget)),
+        PomCompletionKind::Version => target
+            .group
+            .as_deref()
+            .zip(target.artifact.as_deref())
+            .and_then(|(g, a)| repo_dir(repo, &[g, a]))
+            .map_or_else(Vec::new, |dir| scan_versions(&dir, &target.typed, &mut budget)),
+    }
+}
+
+/// Directory listings one completion may read: the scans are interactive, so
+/// they stop before they could be felt, and a huge repository simply yields
+/// fewer suggestions (its shallowest first — the walk is breadth-preferring).
+const SCAN_BUDGET: u32 = 2048;
+/// Suggestion caps per kind: group ids and artifact ids fill a lookup page,
+/// versions list an artifact's releases.
+const MAX_GROUP_OPTIONS: usize = 60;
+const MAX_ARTIFACT_OPTIONS: usize = 60;
+const MAX_VERSION_OPTIONS: usize = 100;
+/// The cap the merged list (local plus Maven Central's) is truncated to.
+pub const MAX_OPTIONS: usize = 100;
+
+/// A directory entry whose name passes the repository layout's alphabet
+/// (mirrors `sources::artifact`'s): letters, digits, `._-`. Path separators
+/// and `..` never pass, so a POM's `${…}`-free text cannot traverse out of
+/// the repository.
+fn segment(name: &str) -> bool {
+    !name.is_empty()
+        && name != "."
+        && name != ".."
+        && name.chars().all(|c| c.is_ascii_alphanumeric() || "._-".contains(c))
+}
+
+/// The subdirectories of `dir` with repository-layout names, spending `budget`
+/// on the listing; `None` when the budget ran out before `dir` was listed.
+fn subdirs(dir: &Path, budget: &mut u32) -> Option<Vec<String>> {
+    if *budget == 0 {
+        return None;
+    }
+    *budget -= 1;
+    let Ok(entries) = std::fs::read_dir(dir) else {
+        return Some(Vec::new());
+    };
+    let mut names = Vec::new();
+    for entry in entries.flatten() {
+        // The budget bounds file-type checks too: a plain listing answers.
+        if entry.file_type().map(|t| t.is_dir()).unwrap_or(false)
+            && let Ok(name) = entry.file_name().into_string()
+            && segment(&name)
+        {
+            names.push(name);
+        }
+    }
+    Some(names)
+}
+
+/// Whether `dir` holds files — a version directory does (jar, pom, the
+/// tracking files), a group path segment never does.
+fn holds_files(dir: &Path, budget: &mut u32) -> bool {
+    if *budget == 0 {
+        return false;
+    }
+    *budget -= 1;
+    let Ok(entries) = std::fs::read_dir(dir) else {
+        return false;
+    };
+    entries.flatten().any(|e| e.file_type().map(|t| t.is_file()).unwrap_or(false))
+}
+
+/// Whether the version directory `dir` holds the version: its `.pom` or a `.jar`. A failed
+/// download leaves only `*.lastUpdated` tracking files behind, for a version that may not
+/// even exist (one typed while the POM was being edited).
+fn installed(dir: &Path, budget: &mut u32) -> bool {
+    if *budget == 0 {
+        return false;
+    }
+    *budget -= 1;
+    let Ok(entries) = std::fs::read_dir(dir) else {
+        return false;
+    };
+    entries.flatten().any(|e| {
+        e.file_type().map(|t| t.is_file()).unwrap_or(false)
+            && e.file_name().to_str().is_some_and(|n| n.ends_with(".pom") || n.ends_with(".jar"))
+    })
+}
+
+/// Whether `dir` is an artifact directory: it holds versions of one artifact,
+/// recognizable by a `maven-metadata*.xml` beside them or a child directory
+/// holding files. A group segment's children are directories without files.
+fn artifact_dir(dir: &Path, budget: &mut u32) -> bool {
+    if *budget == 0 {
+        return false;
+    }
+    *budget -= 1;
+    let Ok(entries) = std::fs::read_dir(dir) else {
+        return false;
+    };
+    for entry in entries.flatten() {
+        let Ok(name) = entry.file_name().into_string() else { continue };
+        if name.starts_with("maven-metadata") {
+            return true;
+        }
+    }
+    let Some(children) = subdirs(dir, budget) else { return false };
+    children.iter().any(|c| holds_files(&dir.join(c), budget))
+}
+
+/// Whether `dir` is a group directory (holds artifact directories) and whether
+/// it also holds deeper group segments worth descending into.
+fn group_dir(dir: &Path, budget: &mut u32) -> Option<(bool, bool)> {
+    let children = subdirs(dir, budget)?;
+    let (mut group, mut descend) = (false, false);
+    for child in &children {
+        if artifact_dir(&dir.join(child), budget) {
+            group = true;
+        } else {
+            descend = true;
+        }
+    }
+    Some((group, descend))
+}
+
+/// The group ids installed under `dir` (which the typed prefix `prefix` —
+/// "" for the repository root — already names), completing the partial last
+/// segment `partial`, shallower groups first.
+fn scan_groups(dir: &Path, prefix: &str, partial: &str, budget: &mut u32) -> Vec<PomCompletionOption> {
+    let mut out = Vec::new();
+    scan_groups_into(dir, prefix, partial, &mut out, budget);
+    out.sort_by(|a, b| a.label.cmp(&b.label));
+    out
+}
+
+fn scan_groups_into(dir: &Path, prefix: &str, partial: &str, out: &mut Vec<PomCompletionOption>, budget: &mut u32) {
+    if out.len() >= MAX_GROUP_OPTIONS {
+        return;
+    }
+    let Some(children) = subdirs(dir, budget) else { return };
+    for name in children {
+        if !name.starts_with(partial) {
+            continue;
+        }
+        let path = dir.join(&name);
+        let label = if prefix.is_empty() { name.clone() } else { format!("{prefix}.{name}") };
+        let Some((group, descend)) = group_dir(&path, budget) else { return };
+        if group {
+            out.push(PomCompletionOption { label: label.clone(), detail: None });
+            if out.len() >= MAX_GROUP_OPTIONS {
+                return;
+            }
+        }
+        // Deeper groups (org.example under org.example's own parent) follow the
+        // shallower ones, so a truncated scan of a huge repository still offers
+        // every first-level segment.
+        if descend {
+            scan_groups_into(&path, &label, "", out, budget);
+        }
+    }
+}
+
+/// The artifact ids installed under the group directory `dir`, completing the
+/// typed prefix, each with its newest installed version as the detail.
+fn scan_artifacts(dir: &Path, typed: &str, budget: &mut u32) -> Vec<PomCompletionOption> {
+    let Some(children) = subdirs(dir, budget) else { return Vec::new() };
+    let mut out = Vec::new();
+    for name in children {
+        if !name.starts_with(typed) || !artifact_dir(&dir.join(&name), budget) {
+            continue;
+        }
+        let detail = newest_version(&dir.join(&name), budget);
+        out.push(PomCompletionOption { label: name, detail });
+    }
+    out.sort_by(|a, b| a.label.cmp(&b.label));
+    out.truncate(MAX_ARTIFACT_OPTIONS);
+    out
+}
+
+/// The newest version directory of the artifact at `dir`, by Maven's ordering.
+fn newest_version(dir: &Path, budget: &mut u32) -> Option<String> {
+    let children = subdirs(dir, budget)?;
+    children.into_iter().filter(|name| installed(&dir.join(name), budget)).max_by(|a, b| compare_versions(a, b))
+}
+
+/// The versions installed of the artifact at `dir`, completing the typed
+/// prefix, newest first.
+fn scan_versions(dir: &Path, typed: &str, budget: &mut u32) -> Vec<PomCompletionOption> {
+    let Some(children) = subdirs(dir, budget) else { return Vec::new() };
+    let mut out: Vec<_> = children
+        .into_iter()
+        .filter(|name| name.starts_with(typed) && installed(&dir.join(name), budget))
+        .map(|name| PomCompletionOption { label: name, detail: None })
+        .collect();
+    out.sort_by(|a, b| compare_versions(&b.label, &a.label));
+    out.truncate(MAX_VERSION_OPTIONS);
+    out
+}
+
+/// The repository directory of the `/`-separated `coordinates` (a group id, or
+/// a group and an artifact id), each segment validated against the layout's
+/// alphabet so POM text cannot walk outside `repo`.
+fn repo_dir(repo: &Path, coordinates: &[&str]) -> Option<PathBuf> {
+    let segments: Vec<&str> = coordinates.iter().flat_map(|c| c.split('.')).collect();
+    segments.iter().all(|s| segment(s)).then(|| segments.iter().fold(repo.to_path_buf(), |p, s| p.join(s)))
+}
+
+/// Maven-ish version order, best-effort (a full `ComparableVersion` is out of
+/// proportion for ordering a lookup): numeric runs compare numerically, letter
+/// runs by their qualifier rank (`alpha < beta < m < rc < snapshot < release <
+/// sp`, unknown ones with releases lexically); missing parts rank as zero.
+fn compare_versions(a: &str, b: &str) -> Ordering {
+    fn tokens(v: &str) -> Vec<String> {
+        v.split(|c: char| !c.is_ascii_alphanumeric()).filter(|t| !t.is_empty()).map(str::to_ascii_lowercase).collect()
+    }
+    fn rank(t: &str) -> Option<u8> {
+        match t {
+            "a" | "alpha" => Some(0),
+            "b" | "beta" => Some(1),
+            "m" | "milestone" => Some(2),
+            "rc" | "cr" => Some(3),
+            "snapshot" => Some(4),
+            "" | "ga" | "final" => Some(5),
+            "sp" => Some(6),
+            _ => None,
+        }
+    }
+    let (a, b) = (tokens(a), tokens(b));
+    for i in 0..a.len().max(b.len()) {
+        let (x, y) = (a.get(i).map(String::as_str), b.get(i).map(String::as_str));
+        let (xn, yn) = (x.and_then(|s| s.parse::<u64>().ok()), y.and_then(|s| s.parse::<u64>().ok()));
+        let order = match (xn, yn) {
+            // Numbers compare numerically; a number outranks a qualifier.
+            (Some(xn), Some(yn)) => xn.cmp(&yn),
+            (Some(_), None) if y.is_some() => return Ordering::Greater,
+            (None, Some(_)) if x.is_some() => return Ordering::Less,
+            _ => {
+                let xr = x.and_then(rank).unwrap_or(5);
+                let yr = y.and_then(rank).unwrap_or(5);
+                if xr != yr { xr.cmp(&yr) } else { x.unwrap_or("").cmp(y.unwrap_or("")) }
+            }
+        };
+        if order != Ordering::Equal {
+            return order;
+        }
+    }
+    Ordering::Equal
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    /// A small local repository: every file is laid out as Maven installs it,
+    /// so the scans recognize group, artifact and version directories.
+    fn repo(dir: &Path) -> PathBuf {
+        let repo = dir.join("repository");
+        for file in [
+            "org/apache/maven/maven-core/4.0.0-rc-5/maven-core-4.0.0-rc-5.jar",
+            "org/apache/maven/plugins/maven-compiler-plugin/3.8.1/maven-compiler-plugin-3.8.1.jar",
+            "org/example/lib/1.0/lib-1.0.jar",
+            "org/example/lib/1.9.1/lib-1.9.1.jar",
+            "org/example/lib/1.10/lib-1.10.jar",
+            "org/example/lib/2.0-beta-1/lib-2.0-beta-1.jar",
+            "org/example/lib/2.0/lib-2.0.pom",
+            "net/nu/netty/4.1.100/netty-4.1.100.jar",
+            // Failed downloads (a version typed while editing): tracking files only, not installed.
+            "org/example/lib/2/lib-2.jar.lastUpdated",
+            "org/example/lib/3.0/lib-3.0.pom.lastUpdated",
+        ] {
+            let path = repo.join(file);
+            std::fs::create_dir_all(path.parent().unwrap()).unwrap();
+            std::fs::write(&path, b"").unwrap();
+        }
+        repo
+    }
+
+    fn target(text: &str, needle: &str) -> Option<PomCompletionTarget> {
+        completion_target(text, (text.find(needle).unwrap() + needle.len()) as u32)
+    }
+
+    #[test]
+    fn completes_each_coordinate_element_of_a_dependency() {
+        let text = "<project><dependencies><dependency>\
+<groupId>org.example</groupId><artifactId>lib</artifactId><version>1.0</version>\
+</dependency></dependencies></project>";
+        let t = target(text, "<groupId>org.example").unwrap();
+        assert_eq!(t.kind, PomCompletionKind::GroupId);
+        assert_eq!(t.typed, "org.example");
+        assert_eq!((t.from, t.to), (44, 55));
+        assert!(t.group.is_none() && t.artifact.is_none());
+
+        let t = target(text, "<artifactId>lib").unwrap();
+        assert_eq!(t.kind, PomCompletionKind::ArtifactId);
+        assert_eq!(t.typed, "lib");
+        assert_eq!(t.group.as_deref(), Some("org.example"));
+        assert!(t.artifact.is_none());
+
+        let t = target(text, "<version>1.0").unwrap();
+        assert_eq!(t.kind, PomCompletionKind::Version);
+        assert_eq!(t.typed, "1.0");
+        assert_eq!(t.group.as_deref(), Some("org.example"));
+        assert_eq!(t.artifact.as_deref(), Some("lib"));
+    }
+
+    #[test]
+    fn completes_while_the_element_is_being_typed_and_the_value_is_empty() {
+        let empty = "<project><dependencies><dependency><groupId></groupId></dependency></dependencies></project>";
+        let t = target(empty, "<groupId>").unwrap();
+        assert_eq!(t.kind, PomCompletionKind::GroupId);
+        assert_eq!(t.typed, "");
+        assert_eq!(t.from, t.to);
+
+        let open = "<project><dependencies><dependency><artifactId>li";
+        let t = target(open, "li").unwrap();
+        assert_eq!(t.kind, PomCompletionKind::ArtifactId);
+        assert_eq!(t.typed, "li");
+        // The value under construction ends with the input and is replaced whole.
+        assert_eq!(t.to, open.len() as u32);
+    }
+
+    #[test]
+    fn completes_only_dependency_coordinates() {
+        // The same elements outside a <dependency> get nothing: a <plugin> is
+        // completed by the repository, not coordinates.
+        let plugin =
+            "<project><build><plugins><plugin><groupId>org.apache.maven</groupId></plugin></plugins></build></project>";
+        assert_eq!(target(plugin, "<groupId>org.apache.maven"), None);
+        // A caret in the end tag, or on a `${property}` value, is not a completion.
+        let text =
+            "<project><dependencies><dependency><groupId>org.example</groupId></dependency></dependencies></project>";
+        assert_eq!(target(text, "</groupId>"), None);
+        let property = "<project><dependencies><dependency><groupId>${example.group}</groupId></dependency></dependencies></project>";
+        assert_eq!(target(property, "${example.group}"), None);
+        // A dependency's groupId is required before its artifacts can be listed.
+        let no_group =
+            "<project><dependencies><dependency><artifactId>lib</artifactId></dependency></dependencies></project>";
+        let t = target(no_group, "<artifactId>lib").unwrap();
+        assert!(t.group.is_none());
+    }
+
+    #[test]
+    fn interpolates_the_poms_own_properties_for_siblings() {
+        let text = "<project>\
+<properties><example.group>org.example</example.group><example.version>2.0</example.version></properties>\
+<dependencies><dependency><groupId>${example.group}</groupId><artifactId>lib</artifactId><version>${example.version}</version></dependency></dependencies>\
+</project>";
+        // The groupId the caret is typing stays a completion; the siblings resolve.
+        let t = target(text, "<artifactId>lib").unwrap();
+        assert_eq!(t.group.as_deref(), Some("org.example"));
+        // A `${property}` under the caret itself gets nothing to complete.
+        assert_eq!(target(text, "<version>${example.version}"), None);
+    }
+
+    #[test]
+    fn local_scan_lists_installed_groups_shallowest_first() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = repo(tmp.path());
+        let options = |typed: &str| {
+            local_options(
+                &repo,
+                &PomCompletionTarget {
+                    from: 0,
+                    to: 0,
+                    typed: typed.into(),
+                    kind: PomCompletionKind::GroupId,
+                    group: None,
+                    artifact: None,
+                },
+            )
+            .into_iter()
+            .map(|o| o.label)
+            .collect::<Vec<_>>()
+        };
+        // Only directories holding artifacts are group ids: `net` and `org`
+        // alone never receive an install, their deeper levels do.
+        assert_eq!(options(""), ["net.nu", "org.apache.maven", "org.apache.maven.plugins", "org.example"]);
+        assert_eq!(options("org"), ["org.apache.maven", "org.apache.maven.plugins", "org.example"]);
+        assert_eq!(options("org."), ["org.apache.maven", "org.apache.maven.plugins", "org.example"]);
+        assert_eq!(options("org.spr"), Vec::<String>::new());
+        assert_eq!(options("net."), ["net.nu"]);
+    }
+
+    #[test]
+    fn local_scan_lists_artifacts_of_the_group_with_their_newest_version() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = repo(tmp.path());
+        let options = |typed: &str| {
+            local_options(
+                &repo,
+                &PomCompletionTarget {
+                    from: 0,
+                    to: 0,
+                    typed: typed.into(),
+                    kind: PomCompletionKind::ArtifactId,
+                    group: Some("org.example".into()),
+                    artifact: None,
+                },
+            )
+            .into_iter()
+            .map(|o| (o.label, o.detail))
+            .collect::<Vec<_>>()
+        };
+        assert_eq!(options(""), [("lib".to_owned(), Some("2.0".to_owned()))]);
+        assert_eq!(options("net"), Vec::<(String, Option<String>)>::new());
+    }
+
+    #[test]
+    fn local_scan_lists_versions_of_the_artifact_newest_first() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = repo(tmp.path());
+        let options = |typed: &str| {
+            local_options(
+                &repo,
+                &PomCompletionTarget {
+                    from: 0,
+                    to: 0,
+                    typed: typed.into(),
+                    kind: PomCompletionKind::Version,
+                    group: Some("org.example".into()),
+                    artifact: Some("lib".into()),
+                },
+            )
+            .into_iter()
+            .map(|o| o.label)
+            .collect::<Vec<_>>()
+        };
+        assert_eq!(options(""), ["2.0", "2.0-beta-1", "1.10", "1.9.1", "1.0"]);
+        assert_eq!(options("1."), ["1.10", "1.9.1", "1.0"]);
+    }
+
+    #[test]
+    fn a_poms_text_cannot_walk_out_of_the_repository() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = repo(tmp.path());
+        for group in ["../../etc", "..", "org/../.."] {
+            let options = local_options(
+                &repo,
+                &PomCompletionTarget {
+                    from: 0,
+                    to: 0,
+                    typed: "".into(),
+                    kind: PomCompletionKind::ArtifactId,
+                    group: Some(group.into()),
+                    artifact: None,
+                },
+            );
+            assert!(options.is_empty(), "{group}");
+        }
+    }
+
+    #[test]
+    fn the_scan_stops_at_the_option_cap() {
+        let tmp = tempfile::tempdir().unwrap();
+        let repo = tmp.path().join("repository");
+        for i in 0..MAX_GROUP_OPTIONS + 10 {
+            let group = repo.join(format!("com/example/g{i}"));
+            std::fs::create_dir_all(group.join("art/1.0")).unwrap();
+            std::fs::write(group.join("art/1.0/art-1.0.jar"), b"").unwrap();
+        }
+        let options = local_options(
+            &repo,
+            &PomCompletionTarget {
+                from: 0,
+                to: 0,
+                typed: "".into(),
+                kind: PomCompletionKind::GroupId,
+                group: None,
+                artifact: None,
+            },
+        );
+        assert_eq!(options.len(), MAX_GROUP_OPTIONS);
+    }
+
+    #[test]
+    fn maven_version_order() {
+        let mut versions = ["2.0", "1.0", "2.0-beta-1", "2.0-alpha-2", "1.10", "1.9.1", "4.0.0-rc-5", "4.0.0-rc-13"];
+        versions.sort_by(|a, b| compare_versions(a, b));
+        assert_eq!(versions, ["1.0", "1.9.1", "1.10", "2.0-alpha-2", "2.0-beta-1", "2.0", "4.0.0-rc-5", "4.0.0-rc-13"]);
+    }
+}

crates/ide-clipboard/src/lib.rs

@@ -27,6 +27,13 @@ pub fn set_text(text: &str, owner: usize) -> std::io::Result<()> {
     imp::set_text(text, owner)
 }
 
+/// The clipboard's plain text, None when it holds none. macOS only (main thread);
+/// Linux reads it asynchronously through GTK in the app, Windows through the WebView.
+#[cfg(target_os = "macos")]
+pub fn text() -> Option<String> {
+    imp::text()
+}
+
 /// Size of `DROPFILES`: `pFiles`, `pt` (two `LONG`s), `fNC`, `fWide`.
 const HEADER: usize = 20;
 
@@ -373,6 +380,14 @@ mod imp {
         })
     }
 
+    pub fn text() -> Option<String> {
+        debug_assert!(MainThreadMarker::new().is_some(), "NSPasteboard access requires the main thread");
+        autoreleasepool(|_| {
+            // SAFETY: the type is an AppKit constant, valid for the process' lifetime.
+            NSPasteboard::generalPasteboard().stringForType(unsafe { NSPasteboardTypeString }).map(|s| s.to_string())
+        })
+    }
+
     pub fn set_text(text: &str, _owner: usize) -> std::io::Result<()> {
         debug_assert!(MainThreadMarker::new().is_some(), "NSPasteboard access requires the main thread");
         autoreleasepool(|_| {

crates/ide-core/src/editor_settings.rs

@@ -67,6 +67,8 @@ pub struct EditorAppearanceSettings {
     /// Smooth caret movement curve: `snappy` | `gliding`.
     pub caret_movement_style: String,
     pub line_numbers: bool,
+    /// Gutter numbering: `absolute` | `relative` | `hybrid` (absolute on the caret line, distances elsewhere).
+    pub line_number_mode: String,
     pub method_separators: bool,
     /// Sub-options of `editor.showWhitespace`.
     pub whitespace_leading: bool,
@@ -96,6 +98,7 @@ impl Default for EditorAppearanceSettings {
             smooth_caret_movement: false,
             caret_movement_style: "snappy".into(),
             line_numbers: true,
+            line_number_mode: "absolute".into(),
             method_separators: false,
             whitespace_leading: true,
             whitespace_inner: true,

crates/ide-core/src/event.rs

@@ -8,13 +8,18 @@
 use crate::{DebugSessionId, Diagnostic, DocId, RunId, ServerId, TaskId, TerminalId, TextChange};
 use serde::{Deserialize, Serialize};
 use specta::Type;
+use std::collections::BTreeMap;
 use std::sync::Arc;
 
+/// What a built-in MCP tool asks the project window for. `AgentRun` runs `command` (a shell
+/// line) in the Run tool window's agent tab `name`, on pipes, answered once the process
+/// started or failed to.
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]
 #[serde(tag = "type", rename_all = "camelCase", rename_all_fields = "camelCase")]
 pub enum McpUiRequest {
     Confirm { client: String, tool: String, subject: String, project: String, detail: Option<String> },
     OpenFile { path: crate::IpcPath, line: Option<u32>, column: Option<u32> },
+    AgentRun { name: String, command: String, cwd: crate::IpcPath, env: BTreeMap<String, String> },
 }
 
 #[derive(Clone, Debug, Serialize, Deserialize, Type)]

crates/ide-core/src/lib.rs

@@ -21,6 +21,7 @@ pub mod process;
 pub mod project_dir;
 pub mod project_roots;
 pub mod proxy_settings;
+pub mod real_path;
 pub mod remote_settings;
 pub mod settings;
 pub mod task;

crates/ide-core/src/output_encoding.rs

@@ -76,7 +76,8 @@ fn decode_tool_output_with_code_page(bytes: &[u8], code_page: u32) -> String {
     text
 }
 
-fn encoding_for_code_page(cp: u32) -> Option<&'static encoding_rs::Encoding> {
+/// The `encoding_rs` encoding of a Windows code page, when it has one.
+pub fn encoding_for_code_page(cp: u32) -> Option<&'static encoding_rs::Encoding> {
     Some(match cp {
         65001 => encoding_rs::UTF_8,
         936 => encoding_rs::GBK,
@@ -101,6 +102,56 @@ fn encoding_for_code_page(cp: u32) -> Option<&'static encoding_rs::Encoding> {
     })
 }
 
+/// The code page Windows console programs write to a pipe in: the OEM code page (GBK on a
+/// Chinese system, Shift_JIS on a Japanese one, EUC-KR on a Korean one, 437 / 850 / 866…
+/// elsewhere). `None` when it is UTF-8 (Windows' "Use Unicode UTF-8" option) or off Windows.
+pub fn console_code_page() -> Option<u32> {
+    #[cfg(windows)]
+    {
+        // SAFETY: GetOEMCP is an argument-less query with no preconditions.
+        let cp = unsafe { windows_sys::Win32::Globalization::GetOEMCP() };
+        (cp != 65001).then_some(cp)
+    }
+    #[cfg(not(windows))]
+    {
+        None
+    }
+}
+
+/// Whether every character of code page `cp` is one byte, so text in it can be decoded
+/// piece by piece.
+#[cfg(windows)]
+pub fn is_single_byte_code_page(cp: u32) -> bool {
+    use windows_sys::Win32::Globalization::{CPINFO, GetCPInfo};
+    // SAFETY: CPINFO is plain data, which GetCPInfo fills in.
+    unsafe {
+        let mut info: CPINFO = std::mem::zeroed();
+        GetCPInfo(cp, &mut info) != 0 && info.MaxCharSize == 1
+    }
+}
+
+/// `bytes` in code page `cp`, decoded by Windows (for the code pages `encoding_rs` lacks,
+/// like the OEM pages 437, 850 or 852).
+#[cfg(windows)]
+pub fn decode_code_page(bytes: &[u8], cp: u32) -> String {
+    use windows_sys::Win32::Globalization::MultiByteToWideChar;
+    let Ok(len) = i32::try_from(bytes.len()) else {
+        return String::from_utf8_lossy(bytes).into_owned();
+    };
+    if len == 0 {
+        return String::new();
+    }
+    // SAFETY: `bytes` holds `len` bytes; no output buffer asks for the length needed.
+    let needed = unsafe { MultiByteToWideChar(cp, 0, bytes.as_ptr(), len, std::ptr::null_mut(), 0) };
+    if needed <= 0 {
+        return String::from_utf8_lossy(bytes).into_owned();
+    }
+    let mut wide = vec![0u16; needed as usize];
+    // SAFETY: `wide` holds `needed` units.
+    let written = unsafe { MultiByteToWideChar(cp, 0, bytes.as_ptr(), len, wide.as_mut_ptr(), needed) };
+    String::from_utf16_lossy(&wide[..written.max(0) as usize])
+}
+
 const STD_PROPERTIES: &[&str] = &["stdout.encoding", "stderr.encoding", "sun.stdout.encoding", "sun.stderr.encoding"];
 const FILE_ENCODING: &str = "file.encoding";
 const TOOL_OPTIONS: &str = "JAVA_TOOL_OPTIONS";

crates/ide-core/src/real_path.rs

@@ -0,0 +1,53 @@
+//! Where a path really lands, and whether it reaches git's own metadata, for writes that must
+//! stay inside a project and out of its `.git`.
+
+use std::path::{Path, PathBuf};
+
+/// `joined` after `..`/symlink resolution as far as the file system allows:
+/// the canonical path when it exists, else the canonicalized deepest existing
+/// ancestor with the still-missing tail resolved textually — so the location
+/// of a missing path is still judged where it would really land.
+pub fn resolve_real(joined: &Path) -> PathBuf {
+    let mut tail = Vec::new();
+    let mut candidate = joined.to_path_buf();
+    let mut real = loop {
+        match dunce::canonicalize(&candidate) {
+            Ok(real) => break real,
+            Err(_) => {
+                let Some(last) = candidate.components().next_back() else {
+                    return joined.to_path_buf();
+                };
+                tail.push(last.as_os_str().to_owned());
+                if !candidate.pop() {
+                    return joined.to_path_buf();
+                }
+            }
+        }
+    };
+    for part in tail.iter().rev() {
+        if part == ".." {
+            real.pop();
+        } else if part != "." {
+            real.push(part);
+        }
+    }
+    real
+}
+
+/// Whether a path (relative to the project root) goes through git's own `.git` folder or file.
+/// git runs what it finds in `.git` (hooks, `gpg.program`, filters), so a content write must
+/// never reach it. Names are normalized for trailing dots and spaces and NTFS stream suffixes;
+/// the caller also checks the short-name-resolved path via [`resolve_real`].
+pub fn names_git_dir(rel: &Path) -> bool {
+    rel.components().any(|part| {
+        let name = part.as_os_str().to_string_lossy();
+        let name = name.split(':').next().unwrap_or_default().trim_end_matches(['.', ' ']);
+        name.eq_ignore_ascii_case(".git")
+    })
+}
+
+/// A resolved write destination under `root` that reaches git's own `.git` metadata, judged by
+/// the name given and by the name the file system resolves it to.
+pub fn reaches_git_dir(root: &Path, real: &Path) -> bool {
+    real.strip_prefix(root).is_ok_and(names_git_dir) || resolve_real(real).strip_prefix(root).is_ok_and(names_git_dir)
+}

crates/ide-core/src/settings.rs

@@ -102,6 +102,11 @@ pub struct AgentSettings {
     #[serde(deserialize_with = "or_default")]
     #[specta(type = WhileRunning)]
     pub while_running: WhileRunning,
+    /// Whether new tasks start in the agent's mode that approves everything (Claude Code's
+    /// bypass permissions, Codex's full access) or in one that asks. User settings only.
+    #[serde(deserialize_with = "or_default")]
+    #[specta(type = NewTaskApprovals)]
+    pub new_task_approvals: NewTaskApprovals,
     /// Settings new tasks of an agent start with: agent id → option id → value.
     #[serde(deserialize_with = "agent_defaults")]
     #[specta(type = BTreeMap<String, BTreeMap<String, String>>)]
@@ -127,6 +132,7 @@ impl Default for AgentSettings {
             expand_tool_output: false,
             send_with: SendKey::Enter,
             while_running: WhileRunning::Queue,
+            new_task_approvals: NewTaskApprovals::Bypass,
             defaults: BTreeMap::new(),
             mcp_servers: BTreeMap::new(),
         }
@@ -270,8 +276,19 @@ pub enum WhileRunning {
     Steer,
 }
 
+/// The approvals new agent tasks start with.
+#[derive(Clone, Copy, Debug, Default, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[serde(rename_all = "camelCase")]
+pub enum NewTaskApprovals {
+    /// The agent's mode that approves everything without asking, when it has one.
+    #[default]
+    Bypass,
+    /// A mode in which the agent asks before edits and commands.
+    Ask,
+}
+
 /// Agents › MCP Server: agents use the IDE's built-in tools.
-#[derive(Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize, Type)]
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize, Type)]
 #[serde(default, rename_all = "camelCase")]
 pub struct McpServerSettings {
     /// Serve the tools on 127.0.0.1 while the IDE runs.
@@ -279,6 +296,16 @@ pub struct McpServerSettings {
     /// Run the tools that change the project or start processes without asking first
     /// (IDEA's brave mode). Read from the IDE's own settings only, never a project's.
     pub run_without_confirmation: bool,
+    /// Finished agent tabs (`run_command`) the Run tool window shows; older ones are archived.
+    pub agent_tab_limit: u32,
+    /// Archived agent tabs kept; older ones are closed.
+    pub agent_archive_limit: u32,
+}
+
+impl Default for McpServerSettings {
+    fn default() -> Self {
+        Self { enabled: false, run_without_confirmation: false, agent_tab_limit: 1, agent_archive_limit: 999 }
+    }
 }
 
 /// Absent profiles retain automatic discovery for existing projects.
@@ -1021,11 +1048,28 @@ pub struct PythonSettings {
     pub interpreter: String,
     /// Activate the interpreter's virtualenv in new terminal sessions.
     pub activate_virtualenv: bool,
+    /// Interpreters the user added to Settings › Python › All Interpreters (executable paths).
+    /// Detection contributes the rest; `hidden_interpreters` removes some of them.
+    pub interpreters: Vec<String>,
+    /// Interpreters the user removed from that list, as executable paths: detection does
+    /// not list them again.
+    pub hidden_interpreters: Vec<String>,
+    /// Hide interpreters that belong to another project (a virtualenv inside its folder).
+    pub hide_other_project_interpreters: bool,
+    /// Show each interpreter's path under its name on the interpreters page.
+    pub show_interpreter_paths: bool,
 }
 
 impl Default for PythonSettings {
     fn default() -> Self {
-        Self { interpreter: String::new(), activate_virtualenv: true }
+        Self {
+            interpreter: String::new(),
+            activate_virtualenv: true,
+            interpreters: Vec::new(),
+            hidden_interpreters: Vec::new(),
+            hide_other_project_interpreters: false,
+            show_interpreter_paths: true,
+        }
     }
 }
 

crates/ide-core/src/tool_path.rs

@@ -61,16 +61,13 @@ pub fn find_command(command: &str, search: &OsStr, root: &Path) -> Option<PathBu
 
 fn is_executable(path: &Path) -> bool {
     let Ok(metadata) = path.metadata() else { return false };
-    if !metadata.is_file() {
-        return false;
-    }
     #[cfg(unix)]
     {
         use std::os::unix::fs::PermissionsExt;
-        metadata.permissions().mode() & 0o111 != 0
+        metadata.is_file() && metadata.permissions().mode() & 0o111 != 0
     }
     #[cfg(not(unix))]
-    true
+    metadata.is_file()
 }
 
 /// [`search_path`]'s directories, in order and once each. Only absolute ones: a

crates/ide-db/Cargo.toml

@@ -37,6 +37,6 @@ zeroize = "1"
 open = "5"
 
 [dev-dependencies]
-tokio = { workspace = true, features = ["rt-multi-thread", "macros"] }
+tokio = { workspace = true, features = ["rt-multi-thread", "macros", "net"] }
 tempfile.workspace = true
 ide-ssh = { workspace = true, features = ["testing"] }

crates/ide-db/src/conn.rs

@@ -241,6 +241,12 @@ pub enum Pool {
     Snowflake(crate::snowflake::SnowflakePool),
 }
 
+/// Some servers and proxies (e.g. Aliyun RDS for MySQL 5.6) advertise `CLIENT_DEPRECATE_EOF` but
+/// still end result sets with legacy EOF packets, which sqlx then fails to read as OK packets.
+fn legacy_eof(e: &sqlx::Error) -> bool {
+    matches!(e, sqlx::Error::Protocol(msg) if msg.starts_with("OK_Packet too short"))
+}
+
 pub(crate) fn db_err(e: sqlx::Error) -> IdeError {
     match &e {
         sqlx::Error::Database(d) => {
@@ -873,9 +879,16 @@ impl Pool {
                 if !tz.is_empty() {
                     opts = opts.timezone(Some(tz.to_owned()));
                 }
-                let manager = MysqlManager { options: opts, init: init.clone(), timeout };
+                let mut manager = MysqlManager { options: opts, init: init.clone(), timeout };
                 // Open once directly so authentication failures retain their database error.
-                let first = manager.connect().await.map_err(db_err)?;
+                let first = match manager.connect().await {
+                    Err(e) if legacy_eof(&e) => {
+                        manager.options = manager.options.clone().deprecate_eof(false);
+                        manager.connect().await
+                    }
+                    first => first,
+                }
+                .map_err(db_err)?;
                 let pool = Bb8Pool::builder().max_size(MAX).connection_timeout(timeout).build_unchecked(manager);
                 let _ = pool.add(first);
                 Ok(Pool::Mysql(ServerPool { inner: pool, closed: AtomicBool::new(false) }))

crates/ide-db/src/watch.rs

@@ -143,9 +143,12 @@ mod tests {
         std::fs::create_dir_all(root.join(".openidea")).unwrap();
         let (count, on_change) = counting();
         let _watch = SourcesWatch::start(&root, None, on_change).unwrap();
+        // FSEvents can deliver the creation of `.openidea/` above after the watch started.
+        std::thread::sleep(Duration::from_secs(1));
+        let seen = count.load(Ordering::SeqCst);
         std::fs::write(root.join(".openidea/settings.toml"), "").unwrap();
         std::fs::write(root.join("main.py"), "").unwrap();
         std::thread::sleep(SETTLE * 3);
-        assert_eq!(count.load(Ordering::SeqCst), 0);
+        assert_eq!(count.load(Ordering::SeqCst), seen);
     }
 }

crates/ide-db/tests/mysql.rs

@@ -183,3 +183,51 @@ async fn a_reused_physical_connection_restores_the_configured_database() -> IdeR
     assert_eq!(pool.execute("SELECT CONNECTION_ID()", 1, &c).await?.rows, backend);
     Ok(())
 }
+
+/// Forwards to the test server, adding `CLIENT_DEPRECATE_EOF` to the capabilities its greeting
+/// advertises, like proxies that set the flag but leave a 5.x server sending legacy EOF packets.
+async fn deprecate_eof_proxy(host: String, port: u16) -> u16 {
+    use tokio::io::{AsyncReadExt, AsyncWriteExt};
+    let listener = tokio::net::TcpListener::bind("127.0.0.1:0").await.unwrap();
+    let local = listener.local_addr().unwrap().port();
+    tokio::spawn(async move {
+        while let Ok((mut client, _)) = listener.accept().await {
+            let mut server = tokio::net::TcpStream::connect((host.as_str(), port)).await.unwrap();
+            tokio::spawn(async move {
+                let mut header = [0u8; 4];
+                server.read_exact(&mut header).await.unwrap();
+                let len = u32::from_le_bytes([header[0], header[1], header[2], 0]) as usize;
+                let mut greeting = vec![0u8; len];
+                server.read_exact(&mut greeting).await.unwrap();
+                // protocol version, NUL-terminated server version, connection id, 8 bytes of
+                // auth data, filler, lower capabilities, charset, status, upper capabilities.
+                let version_end = 1 + greeting[1..].iter().position(|&b| b == 0).unwrap();
+                let upper = version_end + 1 + 4 + 8 + 1 + 2 + 1 + 2;
+                greeting[upper + 1] |= 0x01; // bit 24 of the capability flags
+                client.write_all(&header).await.unwrap();
+                client.write_all(&greeting).await.unwrap();
+                let _ = tokio::io::copy_bidirectional(&mut client, &mut server).await;
+            });
+        }
+    });
+    local
+}
+
+#[tokio::test]
+async fn servers_that_advertise_deprecate_eof_but_send_legacy_eof_packets() -> IdeResult<()> {
+    use ide_db::Pool;
+    let Some((host, port, user, password)) = server() else { return Ok(()) };
+    let source = DataSource {
+        driver: DbDriver::Mysql,
+        host: "127.0.0.1".into(),
+        port: Some(deprecate_eof_proxy(host, port).await),
+        user,
+        ..Default::default()
+    };
+    let pool = Pool::connect(&source, Some(&password), None).await?;
+    assert_eq!(pool.rows("SELECT 1 + 1", 1).await?, vec![vec![Some("2".into())]]);
+    let c = CancellationToken::new();
+    let r = pool.execute("SELECT 'a' UNION ALL SELECT 'b'", 10, &c).await?;
+    assert_eq!(r.rows, vec![vec![Some("a".into())], vec![Some("b".into())]]);
+    Ok(())
+}

crates/ide-extension/src/ledger.rs

@@ -458,16 +458,13 @@ fn canonical_dir(p: &Path) -> PathBuf {
 
 fn is_executable(p: &Path) -> bool {
     let Ok(meta) = std::fs::metadata(p) else { return false };
-    if !meta.is_file() {
-        return false;
-    }
     #[cfg(unix)]
     {
         use std::os::unix::fs::PermissionsExt;
-        meta.permissions().mode() & 0o111 != 0
+        meta.is_file() && meta.permissions().mode() & 0o111 != 0
     }
     #[cfg(not(unix))]
-    true
+    meta.is_file()
 }
 
 /// blake3 of a file, hex.

crates/ide-extension/src/manifest.rs

@@ -34,7 +34,7 @@ use std::path::{Component, Path, PathBuf};
 
 pub const MANIFEST_FILE: &str = "plugin.toml";
 /// The plugin API (engine) version this host implements.
-pub const ENGINE_VERSION: &str = "1.6.0";
+pub const ENGINE_VERSION: &str = "1.7.0";
 /// The 0.1 API, still accepted for contribution-only packages and 0.1 components.
 pub const LEGACY_API: &str = "0.1";
 /// Marketplace categories, in the order they are shown.

crates/ide-host/src/agent_secrets.rs

@@ -0,0 +1,175 @@
+//! Values coding agents are configured with that may be secrets (MCP servers' environment
+//! variables and HTTP headers, agents' environment), kept with the saved passwords in the OS
+//! credential store; the files that configure them keep only the names. Without a credential
+//! store (a headless Linux host) a value is kept in an owner-only file of the user's data
+//! instead, never in a project's files, and the user is told.
+
+use ide_core::event::NotifyLevel;
+use ide_core::{IdeEvent, IdeResult, SharedSink};
+use ide_ssh::secrets::SecretFile;
+use parking_lot::Mutex;
+use std::collections::{BTreeMap, BTreeSet};
+use std::path::{Path, PathBuf};
+
+pub struct AgentSecrets {
+    store: SecretFile,
+    /// Values the credential store refused, by key.
+    local: PathBuf,
+    lock: Mutex<()>,
+}
+
+/// Where [`AgentSecrets::set`] kept a value.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum Kept {
+    Store,
+    LocalFile,
+}
+
+impl AgentSecrets {
+    pub fn new(data_dir: &Path) -> Self {
+        Self::with_store(
+            SecretFile::new(data_dir.join("agent-secrets.json")),
+            data_dir.join("agent-secrets.local.json"),
+        )
+    }
+
+    pub fn with_store(store: SecretFile, local: PathBuf) -> Self {
+        Self { store, local, lock: Mutex::new(()) }
+    }
+
+    pub fn get(&self, key: &str) -> Option<String> {
+        self.store.get(key).or_else(|| self.read_local().remove(key))
+    }
+
+    pub fn set(&self, key: &str, value: &str) -> IdeResult<Kept> {
+        match self.store.set(key, value) {
+            Ok(()) => {
+                self.edit_local(|local| local.remove(key).is_some())?;
+                Ok(Kept::Store)
+            }
+            Err(e) => {
+                tracing::warn!("agent settings: {key} is kept in {}: {}", self.local.display(), e.message);
+                self.edit_local(|local| local.insert(key.to_owned(), value.to_owned()).as_deref() != Some(value))?;
+                Ok(Kept::LocalFile)
+            }
+        }
+    }
+
+    pub fn delete(&self, key: &str) {
+        self.store.delete(key);
+        if let Err(e) = self.edit_local(|local| local.remove(key).is_some()) {
+            tracing::warn!("agent settings: could not forget {key}: {}", e.message);
+        }
+    }
+
+    /// The keys that start with `prefix`, sorted.
+    pub fn keys(&self, prefix: &str) -> Vec<String> {
+        let keys: BTreeSet<String> = self.store.keys().into_iter().chain(self.read_local().into_keys()).collect();
+        keys.into_iter().filter(|k| k.starts_with(prefix)).collect()
+    }
+
+    /// Tells the window that values went to the owner-only file rather than the credential store.
+    pub fn notify_kept_locally(&self, sink: &SharedSink) {
+        sink.emit(IdeEvent::Notify {
+            level: NotifyLevel::Warning,
+            title: "No credential store".into(),
+            body: Some(format!(
+                "Values of agent and MCP server settings are kept in {}, readable only by you.",
+                self.local.display()
+            )),
+        });
+    }
+
+    fn read_local(&self) -> BTreeMap<String, String> {
+        match std::fs::read(&self.local) {
+            Ok(bytes) => serde_json::from_slice(&bytes).unwrap_or_else(|e| {
+                tracing::warn!("agent settings: {}: {e}", self.local.display());
+                BTreeMap::new()
+            }),
+            Err(_) => BTreeMap::new(),
+        }
+    }
+
+    fn edit_local(&self, edit: impl FnOnce(&mut BTreeMap<String, String>) -> bool) -> IdeResult<()> {
+        let _g = self.lock.lock();
+        let mut local = self.read_local();
+        if !edit(&mut local) {
+            return Ok(());
+        }
+        if local.is_empty() {
+            return match std::fs::remove_file(&self.local) {
+                Err(e) if e.kind() != std::io::ErrorKind::NotFound => Err(e.into()),
+                _ => Ok(()),
+            };
+        }
+        if let Some(dir) = self.local.parent() {
+            std::fs::create_dir_all(dir)?;
+        }
+        let bytes = serde_json::to_vec_pretty(&local).map_err(|e| ide_core::IdeError::internal(e.to_string()))?;
+        ide_vfs::write_atomic_private(&self.local, &bytes)?;
+        Ok(())
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use ide_ssh::secrets::testing::{files_containing, use_memory_store};
+    use ide_ssh::secrets::{StoreError, StoreResult, Vault};
+    use std::sync::Arc;
+
+    /// A machine without a credential store (a headless Linux host).
+    struct NoStore;
+
+    impl Vault for NoStore {
+        fn available(&self) -> bool {
+            false
+        }
+        fn get(&self, _: &str, _: &str) -> StoreResult<String> {
+            Err(StoreError::NoDefaultStore)
+        }
+        fn set(&self, _: &str, _: &str, _: &str) -> StoreResult<()> {
+            Err(StoreError::NoDefaultStore)
+        }
+        fn delete(&self, _: &str, _: &str) -> StoreResult<()> {
+            Err(StoreError::NoDefaultStore)
+        }
+    }
+
+    #[test]
+    fn values_go_to_the_credential_store() {
+        use_memory_store();
+        let tmp = tempfile::tempdir().unwrap();
+        let secrets = AgentSecrets::new(tmp.path());
+        assert_eq!(secrets.set("mcp/user/a/env/TOKEN", "value-7c1e").unwrap(), Kept::Store);
+        assert_eq!(files_containing(tmp.path(), "value-7c1e"), Vec::<PathBuf>::new());
+        assert_eq!(AgentSecrets::new(tmp.path()).get("mcp/user/a/env/TOKEN").as_deref(), Some("value-7c1e"));
+        assert_eq!(secrets.keys("mcp/user/"), ["mcp/user/a/env/TOKEN"]);
+        secrets.delete("mcp/user/a/env/TOKEN");
+        assert_eq!(secrets.get("mcp/user/a/env/TOKEN"), None);
+    }
+
+    #[test]
+    fn without_a_credential_store_values_stay_in_an_owner_only_file() {
+        let tmp = tempfile::tempdir().unwrap();
+        let local = tmp.path().join("agent-secrets.local.json");
+        let store = SecretFile::with_vault(
+            tmp.path().join("agent-secrets.json"),
+            |v| serde_json::from_value(v).ok(),
+            Arc::new(NoStore),
+        );
+        let secrets = AgentSecrets::with_store(store, local.clone());
+        assert_eq!(secrets.set("mcp/user/a/env/TOKEN", "value-7c1e").unwrap(), Kept::LocalFile);
+        assert_eq!(files_containing(tmp.path(), "value-7c1e"), std::slice::from_ref(&local));
+        assert_eq!(secrets.get("mcp/user/a/env/TOKEN").as_deref(), Some("value-7c1e"));
+        assert_eq!(secrets.keys("mcp/"), ["mcp/user/a/env/TOKEN"]);
+        #[cfg(unix)]
+        {
+            use std::os::unix::fs::PermissionsExt;
+            assert_eq!(std::fs::metadata(&local).unwrap().permissions().mode() & 0o777, 0o600);
+        }
+        secrets.delete("mcp/user/a/env/TOKEN");
+        assert_eq!(secrets.get("mcp/user/a/env/TOKEN"), None);
+        assert!(!local.exists());
+    }
+}

crates/ide-host/src/bin/openidea-plugin/main.rs

@@ -426,9 +426,9 @@ fn plugins_dir() -> Result<PathBuf, String> {
     if let Some(dir) = std::env::var_os("OPENIDEA_PLUGINS_DIR") {
         return Ok(PathBuf::from(dir));
     }
-    dirs::data_dir()
-        .map(|d| d.join("ai.l0ng.openidea").join("plugins"))
-        .ok_or_else(|| "cannot find the app data directory; set OPENIDEA_PLUGINS_DIR".into())
+    ide_host::data_dirs::data_dir("ai.l0ng.openidea")
+        .map(|d| d.join("plugins"))
+        .map_err(|error| format!("{error}; set OPENIDEA_PLUGINS_DIR"))
 }
 
 #[derive(Default, serde::Serialize, serde::Deserialize)]

crates/ide-host/src/data_dirs.rs

@@ -5,9 +5,52 @@ use std::fs;
 use std::io;
 use std::path::{Path, PathBuf};
 
-/// Moves the rebuildable local data (tools, language servers, indexes, caches);
-/// configuration and roaming data keep following the OS.
+/// Moves the rebuildable local data (tools, language servers, indexes, caches).
 pub const LOCAL_DATA_ENV: &str = "OPENIDEA_LOCAL_DATA_DIR";
+/// Moves the configuration (settings, recent projects, language definitions, window state).
+pub const CONFIG_ENV: &str = "OPENIDEA_CONFIG_DIR";
+/// Moves the user data (plugins, scratches, Local History, trusted projects).
+pub const DATA_ENV: &str = "OPENIDEA_DATA_DIR";
+/// Moves the logs.
+pub const LOG_ENV: &str = "OPENIDEA_LOG_DIR";
+
+/// `$OPENIDEA_CONFIG_DIR/<identifier>` when set, else the OS configuration directory
+/// (Tauri's `app_config_dir`). Like the local data, the identifier keeps release and
+/// per-worktree debug builds apart under one root; a relative path is an error.
+pub fn config_dir(identifier: &str) -> Result<PathBuf, String> {
+    resolve_env(CONFIG_ENV, std::env::var_os(CONFIG_ENV), dirs::config_dir(), identifier)
+}
+
+/// `$OPENIDEA_DATA_DIR/<identifier>` when set, else the OS data directory (Tauri's `app_data_dir`).
+pub fn data_dir(identifier: &str) -> Result<PathBuf, String> {
+    resolve_env(DATA_ENV, std::env::var_os(DATA_ENV), dirs::data_dir(), identifier)
+}
+
+/// `$OPENIDEA_LOG_DIR/<identifier>` when set, else `~/Library/Logs/<identifier>` on macOS and
+/// `<local data>/<identifier>/logs` elsewhere (Tauri's `app_log_dir`).
+pub fn log_dir(identifier: &str) -> Result<PathBuf, String> {
+    let os = if cfg!(target_os = "macos") {
+        dirs::home_dir().map(|home| home.join("Library/Logs").join(identifier))
+    } else {
+        dirs::data_local_dir().map(|dir| dir.join(identifier).join("logs"))
+    };
+    match std::env::var_os(LOG_ENV).filter(|v| !v.is_empty()) {
+        Some(var) => resolve_env(LOG_ENV, Some(var), None, identifier),
+        None => os.ok_or_else(|| "cannot find the log directory".into()),
+    }
+}
+
+/// The directory under `$<env>` when set (absolute, not created here), else under the OS directory.
+fn resolve_env(env: &str, var: Option<OsString>, os: Option<PathBuf>, identifier: &str) -> Result<PathBuf, String> {
+    let Some(root) = var.filter(|v| !v.is_empty()).map(PathBuf::from) else {
+        return os.map(|dir| dir.join(identifier)).ok_or_else(|| format!("cannot find the directory {env} replaces"));
+    };
+    // The working directory depends on how the IDE was launched.
+    if !root.is_absolute() {
+        return Err(format!("{env} must be an absolute path: {}", root.display()));
+    }
+    Ok(root.join(identifier))
+}
 
 /// A custom local-data root chosen in Settings › System Settings › Caches,
 /// stored in the configuration directory. The environment variable still wins.
@@ -51,11 +94,11 @@ fn startup_resolve(
 /// The file holding the custom local-data root, if the platform exposes its
 /// configuration directory. Both startup and Settings use this one path.
 pub fn override_path(identifier: &str) -> Option<PathBuf> {
-    dirs::config_dir().map(|dir| dir.join(identifier).join(OVERRIDE_FILE))
+    config_dir(identifier).ok().map(|dir| dir.join(OVERRIDE_FILE))
 }
 
 fn migration_path(identifier: &str) -> Option<PathBuf> {
-    dirs::config_dir().map(|dir| dir.join(identifier).join(MIGRATION_FILE))
+    config_dir(identifier).ok().map(|dir| dir.join(MIGRATION_FILE))
 }
 
 /// The custom root stored by Settings, if any (validated when it is used).
@@ -493,6 +536,25 @@ fn relative_wrapper(text: &str, source: &Path) -> String {
 mod tests {
     use super::*;
 
+    #[test]
+    fn config_data_and_log_dirs_follow_the_os_unless_their_variable_is_set() {
+        let os = Some(PathBuf::from("/os"));
+        for env in [CONFIG_ENV, DATA_ENV, LOG_ENV] {
+            for var in [None, Some(OsString::new())] {
+                assert_eq!(resolve_env(env, var, os.clone(), "id").unwrap(), PathBuf::from("/os/id"));
+            }
+            let root = std::env::temp_dir().join("openidea-moved");
+            assert_eq!(resolve_env(env, Some(root.clone().into()), os.clone(), "id").unwrap(), root.join("id"));
+            // Release and per-worktree debug builds stay apart under one root.
+            assert_ne!(
+                resolve_env(env, Some(root.clone().into()), None, "dev-a").unwrap(),
+                resolve_env(env, Some(root.clone().into()), None, "dev-b").unwrap()
+            );
+            let error = resolve_env(env, Some("relative/dir".into()), os.clone(), "id").unwrap_err();
+            assert!(error.contains(env) && error.contains("absolute"), "{error}");
+        }
+    }
+
     #[test]
     fn local_dir_follows_the_os_unless_the_variable_is_set() {
         let os = Some(PathBuf::from("/os-local"));

crates/ide-host/src/lib.rs

@@ -3,6 +3,7 @@
 //! wraps one [`Host`] and adds windows and menus; `openidea-server`
 //! runs one on a remote machine and serves it over JSON-RPC ([`rpc`]).
 
+pub mod agent_secrets;
 pub mod data_dirs;
 pub mod environment;
 mod formatter;
@@ -59,7 +60,10 @@ pub struct Host {
     plugin_host: RwLock<std::sync::Weak<plugins::PluginHost>>,
     pub mcp_reports: mcp::Reports,
     pub mcp_requests: mcp::Requests,
+    /// Commands agents run in the Run tool window (`run_command`).
+    pub mcp_agent_runs: mcp::AgentRuns,
     pub trust: trust::TrustStore,
+    pub(crate) mcp_approvals: Arc<trust::McpServerApprovals>,
     pub config_dir: PathBuf,
     /// Persistent user state, including credentials and recovery history.
     pub data_dir: PathBuf,
@@ -91,6 +95,8 @@ pub struct Host {
     proxy_password: ide_ssh::secrets::SecretFile,
     /// The proxy password when it could not be saved (no credential store).
     proxy_session_password: Mutex<Option<String>>,
+    /// Values of agents' and MCP servers' environment variables and headers (see `agent_secrets.rs`).
+    pub agent_secrets: Arc<agent_secrets::AgentSecrets>,
     pub(crate) sink_for: SinkFactory,
     owner: fn(&str) -> &str,
     pub runtime: tokio::runtime::Handle,
@@ -137,9 +143,12 @@ impl Host {
             mcp_executable: RwLock::default(),
             mcp_reports: Default::default(),
             mcp_requests: Default::default(),
+            mcp_agent_runs: Default::default(),
             trust: trust::TrustStore::load(&config_dir, &data_dir),
+            mcp_approvals: Arc::new(trust::McpServerApprovals::load(&data_dir)),
             proxy_password: ide_ssh::secrets::SecretFile::new(data_dir.join("proxy-password.json")),
             proxy_session_password: Mutex::default(),
+            agent_secrets: Arc::new(agent_secrets::AgentSecrets::new(&data_dir)),
             remote: Arc::new(ide_remote::RemoteService::new(ssh.clone(), data_dir.join("remote"))),
             ssh,
             environment: environment::Environment::new(project_environment, local_data_dir.clone()),
@@ -263,6 +272,7 @@ impl Host {
     fn begin_close(&self, window: &str) -> Option<std::thread::JoinHandle<()>> {
         self.mcp_reports.forget_window(window);
         self.mcp_requests.forget_window(window);
+        self.mcp_agent_runs.forget_window(window);
         self.external_logs.write().remove(self.owner_window(window));
         for request in self.project_requests.write().remove(self.owner_window(window)).unwrap_or_default() {
             self.cancel_request(request);

crates/ide-host/src/mcp/check.rs

@@ -0,0 +1,176 @@
+//! `check_files`: fresh diagnostics from the language servers right after an edit, and why a
+//! file could not be checked (no server for it, not installed, crashed, misconfigured…).
+
+use super::editors::problem;
+use crate::mcp::run::timeout;
+use crate::mcp::tool::{Call, Output, Param, ParamType, Tool};
+use ide_core::{IdeError, IdeResult, Severity};
+use ide_lsp::DocumentCheck;
+use serde_json::{Value, json};
+use std::path::PathBuf;
+use std::time::{Duration, Instant};
+
+const DEFAULT_TIMEOUT_MS: usize = 30_000;
+const MAX_FILES: usize = 20;
+
+pub fn check_files() -> Tool {
+    Tool::new(
+        "check_files",
+        &format!(
+            "Checks files with the language servers now and returns their problems: call it after changing files \
+(with any tool, inside or outside the IDE). Each file is synced from disk and saved to its servers, so checks that \
+run on save (rust-analyzer's cargo check) run too; then the call waits until every server answered for the current \
+text and finished the work it started, up to `timeout` milliseconds (default {DEFAULT_TIMEOUT_MS}) for all files. \
+Unlike get_file_problems, this is a fresh analysis, before the inspection profile's filtering.
+
+Per file, `status` says what the problems are worth:
+- checked: every server answered; `problems` is complete (empty means no problems).
+- incomplete: some server was still analysing when the wait ended, or could not check; call again or raise `timeout`.
+- serverUnavailable: no server could check. `servers` gives each one's `status` (missing: not installed; \
+misconfigured; crashed; starting: did not finish starting) and `message`; tell the user, since the IDE has to be \
+fixed (Settings › Languages & Frameworks › Language Servers), and check another way meanwhile (a build or a compiler).
+- noLanguageServer: no language server is configured for this kind of file.
+- untrusted: language servers don't run in an untrusted project.
+- failed: the file could not be opened (`error`).
+`unsavedInEditor` is true when the file has unsaved changes in the IDE: the problems are for the editor's text, not \
+the file on disk. Lines and UTF-16 columns are 1-based."
+        ),
+        |call| async move {
+            let raw = call.str_list("filePaths")?;
+            if raw.is_empty() {
+                return Err(IdeError::invalid("filePaths must name at least one file"));
+            }
+            if raw.len() > MAX_FILES {
+                return Err(IdeError::invalid(format!("at most {MAX_FILES} files at a time")));
+            }
+            let errors_only = call.flag("errorsOnly", true)?;
+            let limit = timeout(&call, DEFAULT_TIMEOUT_MS)?;
+            let mut paths = Vec::new();
+            for p in raw {
+                paths.push(call.resolve_readable(&p).await?);
+            }
+            let checks = paths.into_iter().map(|path| check_one(&call, path, limit, errors_only));
+            let files = futures::future::join_all(checks).await;
+            Output::json(json!({ "files": files }))
+        },
+    )
+    .param(Param::required("filePaths", ParamType::StringList, "Files to check, relative to the project root"))
+    .param(Param::optional(
+        "errorsOnly",
+        ParamType::Boolean,
+        "Whether to return only errors (default) or warnings and hints too",
+    ))
+    .param(Param::optional("timeout", ParamType::Integer, "Milliseconds to wait for the servers at most"))
+}
+
+async fn check_one(call: &Call, path: PathBuf, limit: Duration, errors_only: bool) -> Value {
+    let mut out = json!({ "filePath": call.display(&path) });
+    if !call.project().is_trusted() {
+        out["status"] = "untrusted".into();
+        return out;
+    }
+    match check(call, &path, limit).await {
+        Ok((check, dirty, text)) => {
+            let servers: Vec<Value> = check
+                .servers
+                .iter()
+                .map(|s| {
+                    let mut v = json!({ "name": s.name, "status": s.status, "checked": s.checked });
+                    if let Some(m) = &s.message {
+                        v["message"] = m.clone().into();
+                    }
+                    if s.incomplete {
+                        v["incomplete"] = true.into();
+                    }
+                    if let Some(e) = &s.error {
+                        v["error"] = e.clone().into();
+                    }
+                    v
+                })
+                .collect();
+            out["status"] = file_status(&check).into();
+            out["problems"] = check
+                .diagnostics
+                .into_iter()
+                .filter(|d| !errors_only || d.severity == Severity::Error)
+                .map(|d| problem(d, &text))
+                .collect::<Vec<_>>()
+                .into();
+            out["servers"] = servers.into();
+            if dirty {
+                out["unsavedInEditor"] = true.into();
+            }
+        }
+        Err(e) => {
+            out["status"] = "failed".into();
+            out["error"] = e.message.into();
+        }
+    }
+    out
+}
+
+fn file_status(check: &DocumentCheck) -> &'static str {
+    if check.servers.is_empty() {
+        "noLanguageServer"
+    } else if !check.servers.iter().any(|s| s.checked) {
+        "serverUnavailable"
+    } else if check.servers.iter().all(|s| s.checked && !s.incomplete) {
+        "checked"
+    } else {
+        "incomplete"
+    }
+}
+
+/// The check of `path`, whether it has unsaved changes in the IDE, and its text.
+async fn check(call: &Call, path: &std::path::Path, limit: Duration) -> IdeResult<(DocumentCheck, bool, String)> {
+    let project = call.project().clone();
+    let docs = project.documents.clone();
+    let p = path.to_owned();
+    let at = Instant::now();
+    // Synced now: the file watcher's reload of a change made outside the IDE may not have run.
+    let (doc, changed, dirty) = call
+        .host()
+        .blocking(move || {
+            let before = docs.by_path(&p).and_then(|d| docs.version(d).ok().map(|v| (d, v)));
+            docs.on_disk_changed(std::slice::from_ref(&p));
+            let doc = docs.open(&p)?.id;
+            let changed = before.is_none_or(|(d, v)| d != doc || docs.version(d).is_ok_and(|now| now != v));
+            Ok((doc, changed, docs.is_dirty(doc).unwrap_or(false)))
+        })
+        .await?;
+    let result = project.lsp.check_document(doc, changed.then_some(at), limit, &call.cancel).await;
+    let text = project.documents.text_snapshot(doc).map(|t| t.text).unwrap_or_default();
+    let docs = project.documents.clone();
+    let _ = call
+        .host()
+        .blocking(move || {
+            docs.close(doc);
+            Ok(())
+        })
+        .await;
+    Ok((result?, dirty, text))
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use ide_core::event::ServerStatus;
+    use ide_lsp::CheckedServer;
+
+    fn server(status: ServerStatus, checked: bool, incomplete: bool) -> CheckedServer {
+        CheckedServer { name: "s".into(), status, message: None, checked, incomplete, error: None }
+    }
+
+    #[test]
+    fn statuses_say_whether_the_problems_are_complete() {
+        let check = |servers| file_status(&DocumentCheck { diagnostics: Vec::new(), servers });
+        assert_eq!(check(vec![]), "noLanguageServer");
+        assert_eq!(check(vec![server(ServerStatus::Missing, false, false)]), "serverUnavailable");
+        assert_eq!(check(vec![server(ServerStatus::Ready, true, false)]), "checked");
+        assert_eq!(check(vec![server(ServerStatus::Busy, true, true)]), "incomplete");
+        assert_eq!(
+            check(vec![server(ServerStatus::Ready, true, false), server(ServerStatus::Crashed, false, false)]),
+            "incomplete"
+        );
+    }
+}

crates/ide-host/src/mcp/edit.rs

@@ -112,16 +112,17 @@ fn whole_range(text: &str) -> Range {
 /// Whether two paths name the same file (language servers report canonical paths; on a
 /// case-insensitive file system `a.txt` and `A.txt` are one file).
 fn same_file(a: &Path, b: &Path) -> bool {
-    if a == b || matches!((dunce::canonicalize(a), dunce::canonicalize(b)), (Ok(x), Ok(y)) if x == y) {
-        return true;
-    }
-    #[cfg(unix)]
-    {
-        use std::os::unix::fs::MetadataExt;
-        if let (Ok(x), Ok(y)) = (std::fs::metadata(a), std::fs::metadata(b)) {
-            return x.dev() == y.dev() && x.ino() == y.ino();
-        }
-    }
+    a == b || matches!((dunce::canonicalize(a), dunce::canonicalize(b)), (Ok(x), Ok(y)) if x == y) || same_inode(a, b)
+}
+
+#[cfg(unix)]
+fn same_inode(a: &Path, b: &Path) -> bool {
+    use std::os::unix::fs::MetadataExt;
+    matches!((std::fs::metadata(a), std::fs::metadata(b)), (Ok(x), Ok(y)) if x.dev() == y.dev() && x.ino() == y.ino())
+}
+
+#[cfg(not(unix))]
+fn same_inode(_: &Path, _: &Path) -> bool {
     false
 }
 

crates/ide-host/src/mcp/editors.rs

@@ -65,7 +65,7 @@ async fn current_file(call: Call) -> IdeResult<Output> {
     })
 }
 
-fn problem(d: Diagnostic, text: &str) -> Value {
+pub(super) fn problem(d: Diagnostic, text: &str) -> Value {
     json!({
         "severity": d.severity, "description": d.message,
         "lineContent": text.lines().nth(d.range.start.line as usize).unwrap_or_default(),

crates/ide-host/src/mcp/files.rs

@@ -30,9 +30,14 @@ fn read_file() -> Tool {
         "Reads a file in the project directory or from any project dependency or other project source root.
 Can read text sources inside jar/zip archives; compiled class files are not decompiled.
 Returns numbered lines (1-indexed) as text.
-By default, reads up to 2000 lines starting from the beginning of the file.
+By default, reads up to 2000 lines starting from the beginning of the file; a longer file keeps its first and last
+lines with a `…N lines truncated…` marker between them.
+With `offset` or `limit`, returns exactly lines `offset` to `offset + limit - 1` (fewer at the end of the file),
+followed by `…N more lines; read on with offset=M…` when the file goes on.
 The maximum accepted limit is 5000 lines.",
         |call| async move {
+            // An explicit range is read as asked; the default read of a whole file keeps its head and tail.
+            let window = call.opt_i64("offset")?.is_some() || call.opt_i64("limit")?.is_some();
             let offset = positive(&call, "offset", 1)?;
             let limit = positive(&call, "limit", DEFAULT_READ_LIMIT)?;
             if limit > MAX_READ_LIMIT {
@@ -50,7 +55,7 @@ The maximum accepted limit is 5000 lines.",
                 )));
             }
             let text = crate::ops::fs::read_text(&call.host(), call.window(), path).await?;
-            Ok(Output::text(render_slice(&text, offset as usize, limit as usize)?))
+            Ok(Output::text(render_slice(&text, offset as usize, limit as usize, window)?))
         },
     )
     .param(Param::required("file_path", ParamType::String, util::FILE_PATH_DESCRIPTION))
@@ -70,10 +75,12 @@ fn positive(call: &Call, name: &str, default: i64) -> IdeResult<i64> {
     }
 }
 
-/// Lines `start..` of `text` as `L<n>: <line>`; when more than `max_lines` remain, the first
-/// and the last halves of the budget with a `…N lines truncated…` marker between them.
+/// Lines `start..` of `text` as `L<n>: <line>`, at most `max_lines` of them. A `window` is
+/// exactly the lines from `start` on, then how many lines remain; otherwise, when more than
+/// `max_lines` remain, the first and the last halves of the budget with a `…N lines truncated…`
+/// marker between them.
 /// Lines are the editor's: a trailing line break starts an empty last line.
-fn render_slice(text: &str, start: usize, max_lines: usize) -> IdeResult<String> {
+fn render_slice(text: &str, start: usize, max_lines: usize, window: bool) -> IdeResult<String> {
     let lines: Vec<&str> = text.split('\n').map(|l| l.strip_suffix('\r').unwrap_or(l)).collect();
     let count = lines.len();
     if start > count {
@@ -86,6 +93,15 @@ fn render_slice(text: &str, start: usize, max_lines: usize) -> IdeResult<String>
     if available <= max_lines {
         return Ok(range(start, count));
     }
+    if window {
+        let end = start + max_lines - 1;
+        return Ok(format!(
+            "{}\n\u{2026}{} more lines; read on with offset={}\u{2026}",
+            range(start, end),
+            count - end,
+            end + 1
+        ));
+    }
     let head = max_lines / 2;
     let tail = max_lines - head;
     let head_end = start + head - 1;
@@ -245,7 +261,7 @@ mod tests {
     use super::*;
 
     fn slice(text: &str, start: usize, max: usize) -> String {
-        render_slice(text, start, max).unwrap()
+        render_slice(text, start, max, false).unwrap()
     }
 
     #[test]
@@ -254,18 +270,27 @@ mod tests {
         assert_eq!(slice("a\r\nb\n", 1, 10), "L1: a\nL2: b\nL3: ");
         assert_eq!(slice("", 1, 10), "L1: ");
         assert_eq!(slice("a\nb\nc", 2, 10), "L2: b\nL3: c");
-        assert!(render_slice("", 2, 10).unwrap_err().message.contains("offset exceeds file length"));
-        assert!(render_slice("a\nb", 3, 10).unwrap_err().message.contains("offset exceeds file length"));
+        assert!(render_slice("", 2, 10, true).unwrap_err().message.contains("offset exceeds file length"));
+        assert!(render_slice("a\nb", 3, 10, true).unwrap_err().message.contains("offset exceeds file length"));
     }
 
     #[test]
-    fn keeps_head_and_tail_of_long_slices() {
+    fn keeps_head_and_tail_of_a_long_default_read() {
         let text = (1..=11).map(|n| format!("line {n}")).collect::<Vec<_>>().join("\n");
         assert_eq!(slice(&text, 1, 4), "L1: line 1\nL2: line 2\n…7 lines truncated…\nL10: line 10\nL11: line 11");
         assert_eq!(slice(&text, 3, 4), "L3: line 3\nL4: line 4\n…5 lines truncated…\nL10: line 10\nL11: line 11");
         assert_eq!(slice(&text, 1, 1), "…10 lines truncated…\nL11: line 11");
     }
 
+    #[test]
+    fn reads_an_explicit_range_exactly_and_says_where_to_read_on() {
+        let text = (1..=11).map(|n| format!("line {n}")).collect::<Vec<_>>().join("\n");
+        let window = |start, max| render_slice(&text, start, max, true).unwrap();
+        assert_eq!(window(5, 3), "L5: line 5\nL6: line 6\nL7: line 7\n…4 more lines; read on with offset=8…");
+        assert_eq!(window(1, 1), "L1: line 1\n…10 more lines; read on with offset=2…");
+        assert_eq!(window(10, 3), "L10: line 10\nL11: line 11", "the end of the file needs no marker");
+    }
+
     #[test]
     fn cuts_long_lines_at_utf16_units() {
         let long = "x".repeat(2100);

crates/ide-host/src/mcp/mod.rs

@@ -1,8 +1,9 @@
 //! Built-in IDE tools. Transport and discovery live in `ide-mcp`.
+mod check;
 mod edit;
 mod editors;
 mod requests;
-mod run;
+pub(crate) mod run;
 mod vcs;
 pub use requests::Requests;
 mod files;
@@ -16,6 +17,7 @@ use crate::Host;
 use ide_core::{CancellationToken, IdeError};
 use ide_mcp::{ToolCallError, ToolRegistry};
 pub use reports::{FileProblems, FocusedEditor, Reports};
+pub use run::agent::{AGENT_PARAM, AgentRun, AgentRuns, NAME_PREFIX, SHELL_PARAM};
 use std::path::{Path, PathBuf};
 use std::sync::Arc;
 
@@ -30,6 +32,7 @@ fn tools() -> Vec<tool::Tool> {
     let mut tools = files::tools();
     tools.extend(search::tools());
     tools.extend(editors::tools());
+    tools.push(check::check_files());
     tools.push(symbols::get_symbol_info());
     tools.push(symbols::find_references());
     tools.extend(edit::tools());

crates/ide-host/src/mcp/run/agent_tools.rs

@@ -0,0 +1,418 @@
+//! `run_command` and the tools that follow its tab up: `wait_for_run`, `read_run_output`,
+//! `get_run_status`, `send_run_input`, `stop_run` and `list_runs` (see [`super::agent`]).
+
+use super::agent::{AgentRun, INTERVENTION_ADVICE, TruncateMode, clean_output, tab_name, truncate_lines};
+use super::output::RUN_PREVIEW_MAX_LENGTH;
+use crate::mcp::run::timeout;
+use crate::mcp::tool::{Call, Output, Param, ParamType, Tool};
+use ide_core::{IdeError, IdeResult};
+use serde_json::{Map, Value};
+use std::sync::Arc;
+
+const RUN_TIMEOUT_MS: usize = 10_000;
+const WAIT_TIMEOUT_MS: usize = 30_000;
+const STOP_TIMEOUT_MS: usize = 10_000;
+/// Lines of output returned at most, by default (as JetBrains' `execute_terminal_command`).
+const DEFAULT_MAX_LINES: usize = 2000;
+/// Bytes of the log read for one result at most.
+const READ_CAP: usize = 1 << 20;
+/// Lines of output quoted when a name is still running.
+const BUSY_TAIL_LINES: usize = 20;
+
+const NAME: &str = "Tab name. OpenIDEA shows the tab as `_agent_<name>`; passing the prefixed name works too.";
+const SEQUENCE: &str = "\n\nUsing the same name for every command of one task reuses its tab: a name whose command \
+has finished starts the next command in the same tab. A name whose command is still running is refused (with that \
+command and its last output); stop it with `stop_run` first or use another name. Nothing is stopped implicitly.";
+const INTERVENTIONS: &str = "\n\nThe user sees every tab and can type into it, rerun or stop its command, or close \
+it. Results then carry `interventions` (for example `User input: …` or `The user reran this command at …`) and \
+`advice`: unless the user asked otherwise, stop what you are doing, tell the user you received the intervention and \
+wait for their confirmation before you continue.";
+const OUTPUT: &str = "\n\nThe command runs on pipes, not a terminal, so programs print plain lines (no progress \
+bars). `output` is that text cleaned of escape sequences, at most `maxLinesCount` lines (default 2000): beyond it, \
+`truncateMode` START (default) keeps the end, END the start, MIDDLE both ends, NONE everything, with a \
+`<<<...content truncated...>>>` line where lines were left out and `truncatedLines` saying how many. `outputStart` \
+and `nextOffset` are positions in the tab's raw output log; pass `nextOffset` as `offset` to read on.";
+const MAX_LINES: &str = "Lines of output to return at most (default 2000)";
+const TRUNCATE_MODE: &str = "Which lines to leave out beyond maxLinesCount: START (default, keeps the end), END \
+(keeps the start), MIDDLE (keeps both ends) or NONE";
+
+fn find(call: &Call) -> IdeResult<Arc<AgentRun>> {
+    let name = tab_name(&call.str("name")?)?;
+    call.host()
+        .mcp_agent_runs
+        .get(call.root(), &name)
+        .ok_or_else(|| IdeError::not_found(format!("no agent tab named `{name}` (see list_runs)")))
+}
+
+/// `status` of `run`, with interventions not told yet.
+fn result(run: &AgentRun, extra: Map<String, Value>) -> IdeResult<Output> {
+    let mut out = run.status();
+    out.extend(extra);
+    let interventions = run.take_interventions();
+    if !interventions.is_empty() {
+        out.insert("interventions".into(), interventions.into());
+        out.insert("advice".into(), INTERVENTION_ADVICE.into());
+    }
+    Output::json(Value::Object(out))
+}
+
+/// The output from `from` as the agent reads it: cleaned, then cut to `maxLinesCount` lines
+/// as `truncateMode` says.
+fn output_view(call: &Call, run: &AgentRun, from: u64) -> IdeResult<Map<String, Value>> {
+    let max_lines = match call.opt_i64("maxLinesCount")? {
+        Some(n) if n < 1 => return Err(IdeError::invalid("maxLinesCount must be > 0")),
+        Some(n) => n as usize,
+        None => DEFAULT_MAX_LINES,
+    };
+    let mode = match call.opt_str("truncateMode")? {
+        Some(name) => TruncateMode::parse(&name)
+            .ok_or_else(|| IdeError::invalid("truncateMode must be START, MIDDLE, END or NONE"))?,
+        None => TruncateMode::Start,
+    };
+    let len = run.log_len();
+    let from = from.min(len);
+    // A long output is read from the end that stays.
+    let start = if mode == TruncateMode::Start && len - from > READ_CAP as u64 { len - READ_CAP as u64 } else { from };
+    let (raw, start, end) = run.read(start, READ_CAP)?;
+    let (text, truncated) = truncate_lines(&clean_output(&raw), max_lines, mode);
+    let mut out = Map::new();
+    out.insert("output".into(), text.into());
+    if truncated > 0 {
+        out.insert("truncatedLines".into(), truncated.into());
+    }
+    out.insert("outputStart".into(), start.into());
+    out.insert("nextOffset".into(), end.into());
+    Ok(out)
+}
+
+fn deadline(call: &Call, default: usize) -> IdeResult<tokio::time::Instant> {
+    Ok(tokio::time::Instant::now() + timeout(call, default)?)
+}
+
+fn pattern(call: &Call) -> IdeResult<Option<regex_lite::Regex>> {
+    call.opt_str("pattern")?
+        .filter(|p| !p.is_empty())
+        .map(|p| regex_lite::Regex::new(&p).map_err(|e| IdeError::invalid(format!("invalid pattern: {e}"))))
+        .transpose()
+}
+
+fn offset(call: &Call, name: &str) -> IdeResult<Option<u64>> {
+    match call.opt_i64(name)? {
+        Some(n) if n < 0 => Err(IdeError::invalid(format!("{name} must not be negative"))),
+        n => Ok(n.map(|n| n as u64)),
+    }
+}
+
+fn busy(run: &AgentRun) -> IdeError {
+    let tail = run.tail(run.process_offset(), BUSY_TAIL_LINES, RUN_PREVIEW_MAX_LENGTH).map(|t| t.0).unwrap_or_default();
+    IdeError::invalid(format!(
+        "`{}` is still running `{}`. Stop it with stop_run first, or use another name.\nLast output:\n{}",
+        run.name,
+        run.command(),
+        clean_output(&tail).trim_end()
+    ))
+}
+
+pub fn run_command() -> Tool {
+    Tool::new(
+        "run_command",
+        &format!(
+            "Runs a shell command line in a new or reused tab of OpenIDEA's Run tool window, with the shell of \
+Settings › Tools › Terminal. The user is asked first (unless the IDE runs tools without \
+confirmation). Waits up to `timeout` milliseconds (default {RUN_TIMEOUT_MS}) for the command to finish; a command \
+still running then keeps running, and `wait_for_run`, `read_run_output`, `get_run_status`, `send_run_input` and \
+`stop_run` follow it up by name. Returns the tab's status (`state`: starting, running, stopping, succeeded, failed, \
+crashed, stoppedByAgent, stoppedByUser or startFailed; `exitCode`; `crash` with the signal or exception of a crashed \
+process) and its output so far.{OUTPUT}{SEQUENCE}{INTERVENTIONS}"
+        ),
+        |call| async move {
+            let name = tab_name(&call.str("name")?)?;
+            let command = call.str("command")?;
+            if command.trim().is_empty() {
+                return Err(IdeError::invalid("command must not be empty"));
+            }
+            let cwd = match call.opt_str("workingDirectory")?.filter(|d| !d.trim().is_empty()) {
+                Some(dir) => {
+                    let path = call.resolve_inside(&dir)?;
+                    if !path.is_dir() {
+                        return Err(IdeError::not_found(format!("workingDirectory {} is not a directory", dir)));
+                    }
+                    path
+                }
+                None => call.root().to_path_buf(),
+            };
+            let env = call.args.get("envs").filter(|v| !v.is_null()).map(|_| call.str_map("envs")).transpose()?;
+            let deadline = deadline(&call, RUN_TIMEOUT_MS)?;
+            let host = call.host();
+            let runs = &host.mcp_agent_runs;
+            if let Some(run) = runs.get(call.root(), &name).filter(|r| r.running()) {
+                return Err(busy(&run));
+            }
+            let shown_cwd = call.display(&cwd);
+            let mut detail = format!(
+                "{command}\n\nTab: {name}\nWorking directory: {}",
+                if shown_cwd.is_empty() { ".".to_owned() } else { shown_cwd.clone() }
+            );
+            for (key, value) in env.iter().flatten() {
+                detail.push_str(&format!("\n{key}={value}"));
+            }
+            call.confirm(&name, Some(detail)).await?;
+            let run = runs.prepare(call.root(), call.window(), &name, &command, &shown_cwd).map_err(|r| busy(&r))?;
+            let request = ide_core::event::McpUiRequest::AgentRun {
+                name: name.clone(),
+                command: command.clone(),
+                cwd: cwd.into(),
+                env: env.unwrap_or_default().into_iter().collect(),
+            };
+            if let Err(e) = call.ask(request).await {
+                let error = run.start_error();
+                runs.abandon(&run);
+                return Err(match error {
+                    Some(error) => IdeError::invalid(format!("`{name}` did not start: {error}")),
+                    None => e,
+                });
+            }
+            if let Some(error) = run.start_error() {
+                return Err(IdeError::invalid(format!("`{name}` did not start: {error}")));
+            }
+            let from = run.process_offset();
+            let end = run.wait(deadline, None, from, &call.cancel).await?;
+            let mut extra = output_view(&call, &run, from)?;
+            extra.insert("waitEnded".into(), end.as_str().into());
+            result(&run, extra)
+        },
+    )
+    .write()
+    .param(Param::required("name", ParamType::String, NAME))
+    .param(Param::required(
+        "command",
+        ParamType::String,
+        "Shell command line, e.g. `npm test -- --watch=false` or `cargo build && ./target/debug/app`",
+    ))
+    .param(Param::optional(
+        "workingDirectory",
+        ParamType::String,
+        "Directory inside the project to run in, relative to the project root; default: the project root",
+    ))
+    .param(Param::optional("envs", ParamType::StringMap, "Environment variables added for this command"))
+    .param(Param::optional(
+        "timeout",
+        ParamType::Integer,
+        "Milliseconds to wait for the command to finish before returning (0 returns once it started); the command \
+keeps running after it",
+    ))
+    .param(Param::optional("maxLinesCount", ParamType::Integer, MAX_LINES))
+    .param(Param::optional("truncateMode", ParamType::String, TRUNCATE_MODE))
+}
+
+pub fn wait_for_run() -> Tool {
+    Tool::new(
+        "wait_for_run",
+        &format!(
+            "Waits until the command of an agent tab finishes, its output matches `pattern`, the user intervenes, or \
+`timeout` milliseconds pass (default {WAIT_TIMEOUT_MS}). Cancelling the wait leaves the command running. Returns \
+`waitEnded` (exited, matched, userIntervened or timedOut), the tab's status and the output since `offset`. Use \
+`pattern` to wait for a server to be ready, e.g. `Listening on|Started .* in`.{OUTPUT}{INTERVENTIONS}"
+        ),
+        |call| async move {
+            let run = find(&call)?;
+            let deadline = deadline(&call, WAIT_TIMEOUT_MS)?;
+            let pattern = pattern(&call)?;
+            let from = offset(&call, "offset")?.unwrap_or_else(|| run.process_offset());
+            let end = run.wait(deadline, pattern.as_ref(), from, &call.cancel).await?;
+            let mut extra = output_view(&call, &run, from)?;
+            extra.insert("waitEnded".into(), end.as_str().into());
+            result(&run, extra)
+        },
+    )
+    .param(Param::required("name", ParamType::String, NAME))
+    .param(Param::optional("timeout", ParamType::Integer, "Milliseconds to wait at most"))
+    .param(Param::optional(
+        "pattern",
+        ParamType::String,
+        "Regular expression to wait for in the output after `offset` (as the command wrote it)",
+    ))
+    .param(Param::optional(
+        "offset",
+        ParamType::Integer,
+        "Where in the tab's output log to start: a `nextOffset` from an earlier result. Default: where the current \
+command's output starts",
+    ))
+    .param(Param::optional("maxLinesCount", ParamType::Integer, MAX_LINES))
+    .param(Param::optional("truncateMode", ParamType::String, TRUNCATE_MODE))
+}
+
+pub fn read_run_output() -> Tool {
+    Tool::new(
+        "read_run_output",
+        &format!(
+            "Reads the output log of an agent tab, which goes on across the commands and reruns of the tab: from \
+`offset` (a `nextOffset` from an earlier result), or from its start. Also returns the tab's status.\
+{OUTPUT}{INTERVENTIONS}"
+        ),
+        |call| async move {
+            let run = find(&call)?;
+            let from = offset(&call, "offset")?.unwrap_or(0);
+            let extra = output_view(&call, &run, from)?;
+            result(&run, extra)
+        },
+    )
+    .param(Param::required("name", ParamType::String, NAME))
+    .param(Param::optional("offset", ParamType::Integer, "Where in the log to read from"))
+    .param(Param::optional("maxLinesCount", ParamType::Integer, MAX_LINES))
+    .param(Param::optional("truncateMode", ParamType::String, TRUNCATE_MODE))
+}
+
+pub fn get_run_status() -> Tool {
+    Tool::new(
+        "get_run_status",
+        &format!(
+            "Returns the status of an agent tab: its command, `state` (starting, running, stopping, succeeded, \
+failed, crashed, stoppedByAgent, stoppedByUser or startFailed), `startedBy` (agent, or user when the user reran \
+it), times, `exitCode`, `crash`, `outputLength`, `lastOutputAt` (a running command silent for long may be waiting \
+for input) and `tabClosedAt` when the user closed the tab.{INTERVENTIONS}"
+        ),
+        |call| async move {
+            let run = find(&call)?;
+            result(&run, Map::new())
+        },
+    )
+    .param(Param::required("name", ParamType::String, NAME))
+}
+
+pub fn list_runs() -> Tool {
+    Tool::new(
+        "list_runs",
+        "Lists the agent tabs of the project (those started by `run_command`) with their status.",
+        |call| async move {
+            let runs: Vec<Value> =
+                call.host().mcp_agent_runs.list(call.root()).iter().map(|r| Value::Object(r.status())).collect();
+            Output::json(serde_json::json!({ "runs": runs }))
+        },
+    )
+}
+
+/// What a key does to a command on pipes.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum Key {
+    /// Writes this text to its input.
+    Text(&'static str),
+    /// Ctrl+C: stops it, as `stop_run` does.
+    Interrupt,
+    /// Ctrl+D: ends its input.
+    EndOfInput,
+}
+
+fn key(name: &str) -> IdeResult<Key> {
+    Ok(match name.trim().to_ascii_lowercase().replace(' ', "").as_str() {
+        "enter" | "return" => Key::Text("\n"),
+        "tab" => Key::Text("\t"),
+        "ctrl+c" => Key::Interrupt,
+        "ctrl+d" => Key::EndOfInput,
+        "escape" | "esc" | "backspace" | "ctrl+z" | "ctrl+\\" | "ctrl+l" | "up" | "down" | "left" | "right" => {
+            return Err(IdeError::invalid(format!(
+                "`{name}` is a terminal key, and the command runs on pipes, not a terminal: send text and Enter, \
+Ctrl+C to stop it or Ctrl+D to end its input"
+            )));
+        }
+        _ => return Err(IdeError::invalid(format!("unknown key `{name}`"))),
+    })
+}
+
+pub fn send_run_input() -> Tool {
+    Tool::new(
+        "send_run_input",
+        "Writes to the input of the running command of an agent tab, which runs on pipes: `text` as it is, then \
+`keys` in order: Enter (a line break), Tab, Ctrl+C (stops the command, as `stop_run` does) and Ctrl+D (ends its \
+input). Terminal keys (arrows, Escape, Backspace, Ctrl+Z…) are refused. To answer a prompt, pass the answer as \
+`text` and `keys: [\"Enter\"]`. The user sees the command's output in the tab. Returns the tab's status.",
+        |call| async move {
+            let run = find(&call)?;
+            let text = call.opt_str("text")?.unwrap_or_default();
+            let keys = call.str_list("keys")?.iter().map(|k| key(k)).collect::<IdeResult<Vec<_>>>()?;
+            if text.is_empty() && keys.is_empty() {
+                return Err(IdeError::invalid("pass `text`, `keys` or both"));
+            }
+            let id = run.live_process().ok_or_else(|| IdeError::invalid(format!("`{}` is not running", run.name)))?;
+            call.project().require_trust()?;
+            let host = call.host();
+            let mut data = text;
+            for key in keys {
+                match key {
+                    Key::Text(text) => data.push_str(text),
+                    Key::EndOfInput | Key::Interrupt => {
+                        if !data.is_empty() {
+                            host.processes.write_stdin(id, &std::mem::take(&mut data))?;
+                        }
+                        if key == Key::EndOfInput {
+                            crate::ops::run::close_stdin(&host, id)?;
+                        } else {
+                            run.agent_stopping();
+                            crate::ops::run::stop(&host, &run.window(), id)?;
+                            break;
+                        }
+                    }
+                }
+            }
+            if !data.is_empty() {
+                host.processes.write_stdin(id, &data)?;
+            }
+            result(&run, Map::new())
+        },
+    )
+    .write()
+    .param(Param::required("name", ParamType::String, NAME))
+    .param(Param::optional("text", ParamType::String, "Text to type"))
+    .param(Param::optional("keys", ParamType::StringList, "Keys to press after `text`"))
+}
+
+pub fn stop_run() -> Tool {
+    Tool::new(
+        "stop_run",
+        &format!(
+            "Stops the running command of an agent tab, the way the Run tool window's Stop does: it asks the \
+process tree to exit and, with `force`, kills it. Waits up to `timeout` milliseconds (default {STOP_TIMEOUT_MS}) \
+for it to end and returns the tab's status (`stoppedByAgent` once it ended). A process that ignores the request \
+keeps `stopping`: call again with `force`. The tab stays open with its output."
+        ),
+        |call| async move {
+            let run = find(&call)?;
+            let id = run.live_process().ok_or_else(|| IdeError::invalid(format!("`{}` is not running", run.name)))?;
+            let force = call.flag("force", false)?;
+            let deadline = deadline(&call, STOP_TIMEOUT_MS)?;
+            let host = call.host();
+            run.agent_stopping();
+            crate::ops::run::stop(&host, &run.window(), id)?;
+            if force {
+                // A second Stop kills the tree.
+                crate::ops::run::stop(&host, &run.window(), id)?;
+            }
+            let end = run.wait(deadline, None, run.log_len(), &call.cancel).await?;
+            let mut extra = Map::new();
+            extra.insert("waitEnded".into(), end.as_str().into());
+            result(&run, extra)
+        },
+    )
+    .write()
+    .param(Param::required("name", ParamType::String, NAME))
+    .param(Param::optional("force", ParamType::Boolean, "Kill the process tree instead of asking it to exit"))
+    .param(Param::optional("timeout", ParamType::Integer, "Milliseconds to wait for the command to end"))
+}
+
+pub fn tools() -> Vec<Tool> {
+    vec![run_command(), wait_for_run(), read_run_output(), get_run_status(), send_run_input(), stop_run(), list_runs()]
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn keys_are_what_pipes_can_take() {
+        assert_eq!(key(" enter ").unwrap(), Key::Text("\n"));
+        assert_eq!(key("Ctrl+C").unwrap(), Key::Interrupt);
+        assert_eq!(key("ctrl+d").unwrap(), Key::EndOfInput);
+        assert!(key("Up").unwrap_err().message.contains("runs on pipes"));
+        assert!(key("F13").unwrap_err().message.contains("unknown key"));
+    }
+}

crates/ide-host/src/mcp/run/build.rs

@@ -15,7 +15,6 @@ use std::sync::Arc;
 use std::time::Instant;
 
 const DEFAULT_TIMEOUT_MS: usize = 60_000;
-const MAX_TIMEOUT_MS: usize = 3_600_000;
 const MAX_PROBLEMS: usize = 300;
 /// Console lines attached to a failure whose messages were not parsed.
 const CONSOLE_LINES: usize = 200;
@@ -84,13 +83,13 @@ You have to use this tool after performing edits to validate if the edits are va
 In OpenIDEA the project's build system builds it (Maven, Gradle, Cargo, Go or TypeScript); with `filesToRebuild`, the \
 modules containing those files. Asks the user first for every call. Problems have the project-relative \
 `file` and 1-based `line` / `column`; at most 300 problems are listed, and `isSuccess` is false whenever one of them \
-is an ERROR. On timeout (at most 1 hour; 0 times out at once) the build is stopped.",
+is an ERROR. On timeout (0 times out at once) the build is stopped.",
         |call| async move {
             let files: Vec<String> =
                 call.str_list("filesToRebuild")?.into_iter().filter(|f| !f.trim().is_empty()).collect();
             let rebuild = call.flag("rebuild", false)? && files.is_empty();
             let kind = if rebuild { BuildKind::Rebuild } else { BuildKind::Build };
-            let limit = timeout(&call, DEFAULT_TIMEOUT_MS, MAX_TIMEOUT_MS)?;
+            let limit = timeout(&call, DEFAULT_TIMEOUT_MS)?;
             let mut targets: Vec<Option<PathBuf>> = Vec::new();
             let mut dirs: Vec<PathBuf> = Vec::new();
             for f in &files {

crates/ide-host/src/mcp/run/configs.rs

@@ -19,8 +19,6 @@ use std::sync::Arc;
 use std::time::{Duration, Instant};
 
 const DEFAULT_TIMEOUT_MS: usize = 10_000;
-/// No limit in JetBrains; the process keeps running after the timeout anyway.
-const MAX_TIMEOUT_MS: usize = 1_800_000;
 /// Output of a failed before-launch process kept for the error message.
 const MAX_PROCESS_OUTPUT_LENGTH: usize = 20_000;
 /// A before-launch build gets this long.
@@ -541,7 +539,7 @@ tool window; output files are private and deleted after a day.",
             )?;
             let wait = call.flag("waitForExit", true)?;
             // As JetBrains: `timeout` is ignored without waiting, and 0 returns without waiting.
-            let limit = if wait { Some(timeout(&call, DEFAULT_TIMEOUT_MS, MAX_TIMEOUT_MS)?) } else { None };
+            let limit = if wait { Some(timeout(&call, DEFAULT_TIMEOUT_MS)?) } else { None };
             let envs = call.args.get("envs").filter(|v| !v.is_null()).map(|_| call.str_map("envs")).transpose()?;
             let configs = load_configs(&call).await?;
             let mut config = match &target {

crates/ide-host/src/mcp/run/mod.rs

@@ -1,5 +1,7 @@
-//! Run configurations and builds; every call asks the user first.
+//! Run configurations, builds and agent commands; every start asks the user first.
 
+pub(crate) mod agent;
+mod agent_tools;
 mod build;
 mod configs;
 mod output;
@@ -11,15 +13,22 @@ use ide_core::IdeResult;
 use std::time::Duration;
 
 pub fn tools() -> Vec<Tool> {
-    vec![configs::get_run_configurations(), configs::execute_run_configuration(), build::build_project()]
+    let mut tools =
+        vec![configs::get_run_configurations(), configs::execute_run_configuration(), build::build_project()];
+    tools.extend(agent_tools::tools());
+    tools
 }
 
-/// The `timeout` argument: `default` when absent, at most `max` milliseconds. As in JetBrains
+/// Longest wait: far enough to be no limit, near enough not to overflow a deadline.
+const FOREVER_MS: u64 = 365 * 24 * 60 * 60 * 1000;
+
+/// The `timeout` argument in milliseconds, `default` when absent: the agent decides how long
+/// to wait (long waits are answered on an event stream, see `ide_mcp`). As in JetBrains
 /// (`withTimeoutOrNull`), zero or a negative value times out at once.
-fn timeout(call: &Call, default: usize, max: usize) -> IdeResult<Duration> {
+pub(crate) fn timeout(call: &Call, default: usize) -> IdeResult<Duration> {
     Ok(match call.opt_i64("timeout")? {
         None => Duration::from_millis(default as u64),
         Some(n) if n <= 0 => Duration::ZERO,
-        Some(n) => Duration::from_millis((n as u64).min(max as u64)),
+        Some(n) => Duration::from_millis((n as u64).min(FOREVER_MS)),
     })
 }

crates/ide-host/src/mcp/run/targets.rs

@@ -434,10 +434,23 @@ fn cwd_of(root: &Path, c: &RunConfig) -> String {
     cwd.trim_end_matches('/').to_owned()
 }
 
-/// Configs whose working directory most specifically contains `rel` (ties in their original order).
+/// The directory a config covers: a Cargo workspace member's own directory (its `cargo test -p`
+/// runs from the workspace root), else its working directory.
+fn scope_of(root: &Path, c: &RunConfig) -> String {
+    match c.extras.module.as_deref() {
+        Some(module) if c.kind == "cargo" => {
+            let module = module.replace('\\', "/");
+            let module = module.strip_prefix("./").unwrap_or(&module);
+            if module == "." { String::new() } else { module.trim_end_matches('/').to_owned() }
+        }
+        _ => cwd_of(root, c),
+    }
+}
+
+/// Configs whose scope ([`scope_of`]) most specifically contains `rel` (ties in their original order).
 fn all_closest<'a>(root: &Path, configs: &[&'a RunConfig], rel: &str) -> Vec<&'a RunConfig> {
     let score = |c: &RunConfig| -> Option<usize> {
-        let cwd = cwd_of(root, c);
+        let cwd = scope_of(root, c);
         if cwd.is_empty() { Some(0) } else { (rel == cwd || rel.starts_with(&format!("{cwd}/"))).then_some(cwd.len()) }
     };
     let scored: Vec<(&RunConfig, usize)> = configs.iter().filter_map(|c| score(c).map(|s| (*c, s))).collect();
@@ -922,6 +935,33 @@ mod tests {
         assert_eq!(c.args, ["test", "--", "math::tests::"]);
     }
 
+    #[test]
+    fn a_workspace_member_runs_its_own_tests() {
+        let root = Path::new("/p");
+        let member = |pkg: &str, dir: &str| {
+            let mut c = blank(
+                format!("cargo:test:{pkg}"),
+                "test",
+                "cargo",
+                "cargo".into(),
+                vec!["test".into(), "-p".into(), pkg.into()],
+            );
+            c.is_test = true;
+            c.extras.module = Some(dir.into());
+            c
+        };
+        let mut workspace = blank("cargo:test".into(), "test", "cargo", "cargo".into(), vec!["test".into()]);
+        workspace.is_test = true;
+        let configs = vec![member("ide-agent", "crates/ide-agent"), member("ide-mcp", "crates/ide-mcp"), workspace];
+        let src = "#[cfg(test)]\nmod tests {\n    #[test]\n    fn adds() {}\n}\n";
+        let rel = "crates/ide-mcp/src/stdio.rs";
+        let ts = detect(src, rel);
+        let c = target_config(root, &ts[1], rel, &configs, src).unwrap();
+        assert_eq!(c.args, ["test", "-p", "ide-mcp", "--", "stdio::tests::adds", "--exact"]);
+        let c = target_config(root, &ts[1], "src/lib.rs", &configs, src).unwrap();
+        assert!(!c.args.iter().any(|a| a == "-p"), "outside every member: the workspace's tests, {:?}", c.args);
+    }
+
     #[test]
     fn cargo_test_args_get_one_separator() {
         let root = Path::new("/p");

crates/ide-host/src/mcp/search.rs

@@ -38,6 +38,14 @@ const LINE_WINDOW: usize = 500;
 const PATHS_DESCRIPTION: &str = "Optional list of project-relative glob patterns to filter results. Supports '!' \
 excludes. Trailing '/' expands to '**'. Patterns without '/' are treated as '**/pattern'. Empty strings are ignored.";
 const LIMIT_DESCRIPTION: &str = "Maximum number of results to return";
+const CONTEXT_DESCRIPTION: &str = "Lines around each match to return besides the matched line (`lineText`): \"+N\" the \
+N lines after it (`contextAfter`), \"-N\" the N lines before it (`contextBefore`), \"N\" (or the number N) N lines on \
+each side. At most 50. Default: the matched line only.";
+/// A matched line longer than this (UTF-16 units) is cut to the match and [`SNIPPET_AROUND`] units
+/// on each side of it; a longer context line to its start.
+const MAX_LINE_TEXT: usize = 300;
+const SNIPPET_AROUND: usize = 100;
+const MAX_CONTEXT_LINES: u32 = 50;
 
 pub fn tools() -> Vec<Tool> {
     vec![search_text(), search_regex(), search_symbol(), search_file()]
@@ -49,6 +57,8 @@ fn search_text() -> Tool {
         "Searches for a text substring within project files.
 Use this tool for fast text search with match coordinates.
 Results include match coordinates when available (1-based line/column, end exclusive).
+Each result has the matched line (`lineText`; a long line cut to the match and 100 characters on each side, marked
+with …), and with `context` the lines around it.
 
 Paths are glob patterns relative to the project root.
 Examples: [\"src/**\", \"!**/test/**\"], [\"**/*.kt\"], [\"foo/\"].",
@@ -57,6 +67,7 @@ Examples: [\"src/**\", \"!**/test/**\"], [\"**/*.kt\"], [\"foo/\"].",
     .param(Param::required("q", ParamType::String, "Text to search for"))
     .param(Param::optional("paths", ParamType::StringList, PATHS_DESCRIPTION))
     .param(Param::optional("limit", ParamType::Integer, LIMIT_DESCRIPTION))
+    .param(Param::optional("context", ParamType::String, CONTEXT_DESCRIPTION))
     .output(result_schema())
 }
 
@@ -66,6 +77,8 @@ fn search_regex() -> Tool {
         "Searches for regex matches within project files.
 Use this tool when you need regex search with match coordinates.
 Results include match coordinates when available (1-based line/column, end exclusive).
+Each result has the matched line (`lineText`; a long line cut to the match and 100 characters on each side, marked
+with …), and with `context` the lines around it.
 The pattern uses Rust regex syntax and is case-sensitive; prefix `(?i)` to ignore case.
 
 Paths are glob patterns relative to the project root.
@@ -75,6 +88,7 @@ Examples: [\"src/**\", \"!**/test/**\"], [\"**/*.kt\"], [\"foo/\"].",
     .param(Param::required("q", ParamType::String, "Regex pattern to search for"))
     .param(Param::optional("paths", ParamType::StringList, PATHS_DESCRIPTION))
     .param(Param::optional("limit", ParamType::Integer, LIMIT_DESCRIPTION))
+    .param(Param::optional("context", ParamType::String, CONTEXT_DESCRIPTION))
     .output(result_schema())
 }
 
@@ -84,6 +98,7 @@ fn search_symbol() -> Tool {
         "Searches for symbols (classes, methods, fields).
 Use this tool for semantic lookup by identifier fragments.
 Results include match coordinates when available (1-based line/column, end exclusive).
+Project results have their line (`lineText`), and with `context` the lines around it.
 
 Paths are glob patterns relative to the project root.
 By default this searches project symbols only.
@@ -99,6 +114,7 @@ If you don't find a suitable result, try again with include_external=true to sea
 with include_external=true.",
     ))
     .param(Param::optional("limit", ParamType::Integer, LIMIT_DESCRIPTION))
+    .param(Param::optional("context", ParamType::String, CONTEXT_DESCRIPTION))
     .output(result_schema())
 }
 
@@ -145,6 +161,13 @@ struct SearchItem {
     name: Option<String>,
     #[serde(skip_serializing_if = "Option::is_none")]
     container: Option<String>,
+    /// The text of `start_line` (cut when long).
+    #[serde(skip_serializing_if = "Option::is_none")]
+    line_text: Option<String>,
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    context_before: Vec<String>,
+    #[serde(skip_serializing_if = "Vec::is_empty")]
+    context_after: Vec<String>,
 }
 
 impl SearchItem {
@@ -182,7 +205,9 @@ fn result_schema() -> Value {
                 "type": "object",
                 "properties": {
                     "filePath": string, "startLine": int, "startColumn": int, "endLine": int, "endColumn": int,
-                    "name": string, "container": string,
+                    "name": string, "container": string, "lineText": string,
+                    "contextBefore": { "type": "array", "items": string },
+                    "contextAfter": { "type": "array", "items": string },
                 },
                 "required": ["filePath"],
             } },
@@ -207,6 +232,87 @@ fn query(call: &Call, empty: &str) -> IdeResult<String> {
     Ok(q)
 }
 
+// --- matched lines -------------------------------------------------------------
+
+/// The `context` argument as (lines before, lines after).
+fn context(call: &Call) -> IdeResult<(u32, u32)> {
+    let invalid = || IdeError::invalid("context must be \"+N\", \"-N\" or N (lines after, before, or on each side)");
+    let (sign, n) = match call.args.get("context") {
+        None | Some(Value::Null) => return Ok((0, 0)),
+        Some(Value::Number(n)) => (None, n.as_u64().ok_or_else(invalid)?),
+        Some(Value::String(s)) => {
+            let s = s.trim();
+            match s.strip_prefix('+').map(|r| ('+', r)).or_else(|| s.strip_prefix('-').map(|r| ('-', r))) {
+                Some((sign, rest)) => (Some(sign), rest.trim().parse().map_err(|_| invalid())?),
+                None => (None, s.parse().map_err(|_| invalid())?),
+            }
+        }
+        Some(_) => return Err(invalid()),
+    };
+    let n = (n.min(MAX_CONTEXT_LINES as u64)) as u32;
+    Ok(match sign {
+        Some('+') => (0, n),
+        Some(_) => (n, 0),
+        None => (n, n),
+    })
+}
+
+/// `line`, or when longer than [`MAX_LINE_TEXT`] UTF-16 units, the part from [`SNIPPET_AROUND`]
+/// units before 0-based UTF-16 column `start` to as many after `end`, with `…` where it was cut.
+fn snippet(line: &str, start: usize, end: usize) -> String {
+    let units: usize = line.chars().map(char::len_utf16).sum();
+    if units <= MAX_LINE_TEXT {
+        return line.to_owned();
+    }
+    let from = start.saturating_sub(SNIPPET_AROUND);
+    let to = end.max(start).saturating_add(SNIPPET_AROUND).min(units);
+    let (mut out, mut at) = (String::new(), 0);
+    for c in line.chars() {
+        if at >= from && at < to {
+            out.push(c);
+        }
+        at += c.len_utf16();
+    }
+    let before = if from > 0 { "\u{2026}" } else { "" };
+    let after = if to < units { "\u{2026}" } else { "" };
+    format!("{before}{out}{after}")
+}
+
+/// A context line: its first [`MAX_LINE_TEXT`] UTF-16 units.
+fn context_line(line: &str) -> String {
+    snippet(line, 0, MAX_LINE_TEXT.saturating_sub(SNIPPET_AROUND))
+}
+
+/// Fills `line_text` and the context of `items`, whose files are `absolute(item)` (none: left
+/// as they are); each file is read once, with unsaved editor text.
+async fn fill_lines(
+    call: &Call,
+    items: &mut [SearchItem],
+    absolute: impl Fn(&SearchItem) -> Option<PathBuf>,
+    (before, after): (u32, u32),
+) {
+    let host = call.host();
+    let mut current: Option<(PathBuf, Option<Vec<String>>)> = None;
+    for item in items {
+        let (Some(path), Some(line)) = (absolute(item), item.start_line) else { continue };
+        if current.as_ref().is_none_or(|(p, _)| p != &path) {
+            let text = crate::ops::fs::read_text(&host, call.window(), path.clone()).await.ok();
+            let lines = text.map(|t| t.split('\n').map(|l| l.strip_suffix('\r').unwrap_or(l).to_owned()).collect());
+            current = Some((path, lines));
+        }
+        let Some((_, Some(lines))) = &current else { continue };
+        let index = line as usize - 1;
+        let Some(text) = lines.get(index) else { continue };
+        let start = item.start_column.unwrap_or(1) as usize - 1;
+        let end = if item.end_line == Some(line) { item.end_column.map_or(start, |c| c as usize - 1) } else { start };
+        item.line_text = Some(snippet(text, start, end));
+        let first = index.saturating_sub(before as usize);
+        item.context_before = lines[first..index].iter().map(|l| context_line(l)).collect();
+        let last = (index + after as usize).min(lines.len() - 1);
+        item.context_after = lines[index + 1..=last].iter().map(|l| context_line(l)).collect();
+    }
+}
+
 // --- path globs ----------------------------------------------------------------
 
 /// The `paths` argument: project-relative globs, `!` excludes.
@@ -416,6 +522,7 @@ struct TextHit {
 async fn text_search(call: Call, is_regex: bool) -> IdeResult<Output> {
     let pattern = query(&call, if is_regex { "Regex pattern is empty" } else { "Search text is empty" })?;
     let limit = limit(&call, DEFAULT_LIMIT)?;
+    let around = context(&call)?;
     let scope = PathScope::new(call.root(), &call.str_list("paths")?)?;
     // Globs Find in Files cannot take are applied afterwards, so the engine must not
     // stop at `limit` matches the filter may drop.
@@ -494,7 +601,7 @@ async fn text_search(call: Call, is_regex: bool) -> IdeResult<Output> {
     let more = hits.len() > limit || summary.limit_hit || timed_out;
     hits.truncate(limit);
     extend_spanning(&call, &query, &mut hits, spanning).await;
-    let items = hits
+    let mut items: Vec<SearchItem> = hits
         .into_iter()
         .map(|h| SearchItem {
             file_path: h.file_path,
@@ -505,6 +612,9 @@ async fn text_search(call: Call, is_regex: bool) -> IdeResult<Output> {
             ..Default::default()
         })
         .collect();
+    let absolute: std::collections::HashMap<&str, &Path> =
+        files.iter().map(|(path, file)| (path.as_str(), file.path.0.as_path())).collect();
+    fill_lines(&call, &mut items, |item| absolute.get(item.file_path.as_str()).map(|p| p.to_path_buf()), around).await;
     let partial_result_reason = timed_out.then_some(SEARCH_TIMEOUT_PARTIAL_RESULT_REASON);
     Output::json(SearchResult { items, more, partial_result_reason })
 }
@@ -726,6 +836,7 @@ async fn symbol_search(call: Call) -> IdeResult<Output> {
     let started = Instant::now();
     let q = query(&call, "Search query is empty")?;
     let limit = limit(&call, SYMBOL_SEARCH_DEFAULT_LIMIT)?;
+    let around = context(&call)?;
     let scope = PathScope::new(call.root(), &call.str_list("paths")?)?;
     let external = call.flag("include_external", false)?;
     let host = call.host();
@@ -775,6 +886,13 @@ async fn symbol_search(call: Call) -> IdeResult<Output> {
     }
     let more = items.len() > limit || timed_out;
     items.truncate(limit);
+    // Project files (relative paths, or absolute ones of content roots); library URIs are left out.
+    let root = call.root().to_path_buf();
+    let absolute = |item: &SearchItem| {
+        let path = Path::new(&item.file_path);
+        (!item.file_path.contains("://")).then(|| if path.is_absolute() { path.to_path_buf() } else { root.join(path) })
+    };
+    fill_lines(&call, &mut items, absolute, around).await;
     let indexing = indexing_before || project.index.status().indexing;
     let partial_result_reason = if indexing {
         Some(INDEXING_PARTIAL_RESULT_REASON)
@@ -869,6 +987,17 @@ mod tests {
         assert_eq!(byte_at("ab", 5), None);
     }
 
+    #[test]
+    fn long_lines_are_cut_around_the_match() {
+        assert_eq!(snippet("short line", 0, 5), "short line");
+        let line = format!("{}needle{}", "a".repeat(400), "b".repeat(400));
+        let cut = snippet(&line, 400, 406);
+        assert_eq!(cut, format!("\u{2026}{}needle{}\u{2026}", "a".repeat(100), "b".repeat(100)));
+        let start = snippet(&line, 0, 0);
+        assert!(start.starts_with('a') && start.ends_with('\u{2026}') && start.chars().count() == 101);
+        assert_eq!(context_line(&"x".repeat(1000)).chars().count(), MAX_LINE_TEXT + 1);
+    }
+
     #[test]
     fn path_scopes() {
         let (_dir, root) = root();

crates/ide-host/src/ops/agent.rs

@@ -381,7 +381,7 @@ fn persist_mcp_map(
     Ok(())
 }
 
-fn update_mcp_maps<F>(host: &Host, window: &str, f: F) -> IdeResult<Vec<McpServer>>
+fn update_mcp_maps<F>(host: &Host, window: &str, approve: Option<&str>, f: F) -> IdeResult<Vec<McpServer>>
 where
     F: FnOnce(&mut McpServerMap, &mut McpServerMap, Option<&std::path::Path>) -> Result<(), String>,
 {
@@ -390,43 +390,83 @@ where
     let prev_workspace = workspace.clone();
     let project_root = project.as_ref().map(|p| p.root.as_path());
     f(&mut user, &mut workspace, project_root).map_err(IdeError::invalid)?;
+    if let (Some(name), Some(p)) = (approve, &project)
+        && let Some(server) = workspace.get(name)
+    {
+        host.mcp_approvals.approve(&p.root, name, server)?;
+    }
     if workspace != prev_workspace {
         persist_mcp_map(host, project.as_ref(), McpScope::Workspace, &workspace)?;
     }
     if user != prev_user {
         persist_mcp_map(host, project.as_ref(), McpScope::User, &user)?;
     }
-    Ok(ide_agent::mcp::servers_from_settings(&user, &workspace))
+    Ok(listed(host, project.as_ref(), &user, workspace))
+}
+
+/// Workspace servers the user hasn't turned on in Settings are listed as off: agents don't start them.
+fn listed(
+    host: &Host,
+    project: Option<&std::sync::Arc<crate::Project>>,
+    user: &McpServerMap,
+    workspace: McpServerMap,
+) -> Vec<McpServer> {
+    let workspace = match project {
+        Some(p) => host.mcp_approvals.apply(&p.root, workspace),
+        None => workspace,
+    };
+    ide_agent::mcp::servers_from_settings(user, &workspace)
+}
+
+/// The MCP servers agent sessions of the project at `root` get: the user's, and the project's the
+/// user turned on.
+pub(crate) fn session_mcp_servers(
+    settings: &ide_workspace::SettingsStore,
+    approvals: &crate::trust::McpServerApprovals,
+    root: &std::path::Path,
+) -> Vec<McpServer> {
+    use ide_workspace::settings::SettingsScope;
+    let user = settings.layer(SettingsScope::Global).agents.mcp_servers;
+    let workspace = approvals.apply(root, settings.layer(SettingsScope::Project).agents.mcp_servers);
+    ide_agent::mcp::servers_from_settings(&user, &workspace)
 }
 
 /// Lists configured MCP servers across User (`settings.toml`) and Workspace (`.openidea/settings.toml`) scopes.
 pub fn mcp_list(host: &Host, window: &str) -> IdeResult<Vec<McpServer>> {
-    let (user, workspace, _) = mcp_maps(host, window);
-    Ok(ide_agent::mcp::servers_from_settings(&user, &workspace))
+    let (user, workspace, project) = mcp_maps(host, window);
+    Ok(listed(host, project.as_ref(), &user, workspace))
 }
 
-/// Creates or updates a User or Workspace MCP server and returns the updated list.
+/// Creates or updates a User or Workspace MCP server and returns the updated list. A Workspace
+/// server saved here is one the user turned on.
 pub fn mcp_save(host: &Host, window: &str, input: McpServerInput) -> IdeResult<Vec<McpServer>> {
-    update_mcp_maps(host, window, |user, workspace, project_root| {
+    let approve = (input.scope == McpScope::Workspace).then(|| input.name.trim().to_owned());
+    update_mcp_maps(host, window, approve.as_deref(), |user, workspace, project_root| {
         ide_agent::mcp::apply_save(user, workspace, project_root.is_some(), input)
     })
 }
 
 /// Enables or disables an MCP server and returns the updated list.
 pub fn mcp_set_enabled(host: &Host, window: &str, id: String, enabled: bool) -> IdeResult<Vec<McpServer>> {
-    update_mcp_maps(host, window, |user, workspace, _| {
+    let approve = ide_agent::mcp::parse_server_id(&id)
+        .filter(|(scope, _)| enabled && *scope == McpScope::Workspace)
+        .map(|(_, name)| name.to_owned());
+    update_mcp_maps(host, window, approve.as_deref(), |user, workspace, _| {
         ide_agent::mcp::apply_set_enabled(user, workspace, &id, enabled).map(|_| ())
     })
 }
 
 /// Removes a User or Workspace MCP server and returns the updated list.
 pub fn mcp_remove(host: &Host, window: &str, id: String) -> IdeResult<Vec<McpServer>> {
-    update_mcp_maps(host, window, |user, workspace, _| ide_agent::mcp::apply_remove(user, workspace, &id).map(|_| ()))
+    update_mcp_maps(host, window, None, |user, workspace, _| {
+        ide_agent::mcp::apply_remove(user, workspace, &id).map(|_| ())
+    })
 }
 
-/// Copies MCP servers from `.mcp.json` and `.vscode/mcp.json` into the workspace settings once.
+/// Copies MCP servers from `.mcp.json` and `.vscode/mcp.json` into the workspace settings once;
+/// they stay off until the user turns them on.
 pub fn mcp_import(host: &Host, window: &str) -> IdeResult<Vec<McpServer>> {
-    update_mcp_maps(host, window, |_, workspace, project_root| {
+    update_mcp_maps(host, window, None, |_, workspace, project_root| {
         let root = project_root.ok_or_else(|| "Open a project to import workspace MCP servers".to_string())?;
         ide_agent::mcp::apply_import(workspace, root);
         Ok(())
@@ -550,4 +590,43 @@ mod tests {
             assert!(validate_project_root(&root, Some(&rejected)).is_err(), "{rejected:?}");
         }
     }
+
+    #[test]
+    fn sessions_get_the_users_servers_and_the_projects_turned_on_ones() {
+        let tmp = tempfile::tempdir().unwrap();
+        let (config, root) = (tmp.path().join("config"), tmp.path().join("project"));
+        std::fs::create_dir_all(&config).unwrap();
+        std::fs::create_dir_all(root.join(".openidea")).unwrap();
+        std::fs::write(config.join("settings.toml"), "[agents.mcpServers.shared]\ncommand = \"user-cmd\"\n").unwrap();
+        std::fs::write(
+            root.join(".openidea/settings.toml"),
+            "[agents.mcpServers.shared]\ncommand = \"project-cmd\"\n\n[agents.mcpServers.extra]\ncommand = \"extra\"\n",
+        )
+        .unwrap();
+        let settings = ide_workspace::SettingsStore::load(&config, Some(&root));
+        let approvals = crate::trust::McpServerApprovals::load(&tmp.path().join("data"));
+        let on = |servers: Vec<McpServer>| -> Vec<(McpScope, String, String)> {
+            servers
+                .into_iter()
+                .filter(|s| s.enabled)
+                .map(|s| (s.scope, s.name, s.command.unwrap_or_default()))
+                .collect()
+        };
+        assert_eq!(
+            on(session_mcp_servers(&settings, &approvals, &root)),
+            [(McpScope::User, "shared".to_owned(), "user-cmd".to_owned())]
+        );
+
+        let extra = settings.layer(ide_workspace::settings::SettingsScope::Project).agents.mcp_servers["extra"].clone();
+        approvals.approve(&root, "extra", &extra).unwrap();
+        assert!(on(session_mcp_servers(&settings, &approvals, &root)).contains(&(
+            McpScope::Workspace,
+            "extra".to_owned(),
+            "extra".to_owned()
+        )));
+        // Remembered across restarts, and only for this project.
+        let reloaded = crate::trust::McpServerApprovals::load(&tmp.path().join("data"));
+        assert!(reloaded.approved(&root, "extra", &extra));
+        assert!(!reloaded.approved(&tmp.path().join("other"), "extra", &extra));
+    }
 }

crates/ide-host/src/ops/build.rs

@@ -2,16 +2,18 @@
 //! Build › Build Project (compiling with the project's build system).
 mod workspace;
 
+use super::dependencies::{MavenCentralArtifacts, MavenCentralGroups, MavenCentralVersions};
 use crate::ops::Channel;
 use crate::rpc::Dispatcher;
 use crate::{Host, Project, apply_workspace_edit};
 
 use ide_build::compile::{self, BuildEvent, BuildKind, BuildResult};
 use ide_build::maven::PomGoto;
+use ide_build::maven::completion::{PomCompletion, PomCompletionOption};
 use ide_build::pom_edit::{ArtifactKey, Exclusion};
 use ide_build::{BuildModel, BuildTool, SyncOptions, SyncProgress};
 use ide_core::settings::Settings;
-use ide_core::{FileEdit, IdeError, IdeEvent, IdeResult, Location, Pos, Range, RequestId, WorkspaceEdit};
+use ide_core::{DocId, FileEdit, IdeError, IdeEvent, IdeResult, Location, Pos, Range, RequestId, WorkspaceEdit};
 use std::path::Path;
 
 fn join_err(e: tokio::task::JoinError) -> IdeError {
@@ -311,10 +313,11 @@ pub async fn build_sync(
     if tool == BuildTool::Gradle {
         // The sync may report project folders outside the project (`includeFlat`): index and list them.
         project.refresh_index_scope();
-        project.sink.emit(ide_core::IdeEvent::ProjectRootsChanged { root: project.root.clone().into() });
         let p = project.clone();
         tokio::task::spawn_blocking(move || p.refresh_repositories());
     }
+    // New source folders and dependency versions: the Project view and External Libraries reload.
+    project.sink.emit(ide_core::IdeEvent::ProjectRootsChanged { root: project.root.clone().into() });
     if tool == BuildTool::Maven
         && model.maven.is_some()
         && let Some(bridge) = &project.kotlin_bridge
@@ -453,7 +456,8 @@ pub async fn maven_dependency_declaration(
 /// absolute for a parent POM opened from the local repository): the definition of the
 /// `${property}` at the caret, or the `<dependencyManagement>` / `<pluginManagement>`
 /// entry providing the dependency's / plugin's version, along the parent chain (into
-/// the local repository when a parent is not in the project). `None` when nothing
+/// the local repository when a parent is not in the project), else the artifact's own
+/// POM (a project module's, or the local repository's). `None` when nothing
 /// resolvable is under the caret.
 pub async fn maven_goto_declaration(host: &Host, window: &str, pom: String, pos: Pos) -> IdeResult<Option<PomGoto>> {
     let project = host.project(window)?;
@@ -464,12 +468,107 @@ pub async fn maven_goto_declaration(host: &Host, window: &str, pom: String, pos:
         let settings = project.settings.effective();
         let repo = ide_sdk::apply::maven_local_repository(&project.root, &settings)
             .or_else(ide_build::maven::default_local_repo);
-        Ok(ide_build::maven::goto_declaration(&text, &path, pos, repo))
+        let modules = || {
+            let model = load(&project.root, &project.build_cache_dir(), &settings).maven.unwrap_or_default();
+            model
+                .projects
+                .into_iter()
+                .map(|p| ide_build::maven::ModulePom {
+                    group_id: p.group_id,
+                    artifact_id: p.artifact_id,
+                    pom: project.root.join(&p.pom),
+                })
+                .collect()
+        };
+        Ok(ide_build::maven::goto_declaration_in(&text, &path, pos, repo, modules))
     })
     .await
     .map_err(join_err)?
 }
 
+/// How long completion waits for Maven Central before answering from the local repository.
+const CENTRAL_WAIT: std::time::Duration = std::time::Duration::from_secs(1);
+
+/// Completion of the `<dependency>` coordinate the caret (`offset`, UTF-16) sits
+/// in the value of in the POM `doc`: the coordinates installed in the local
+/// repository (Settings › Maven's, else `~/.m2/repository`) — group ids,
+/// the chosen group's artifacts, the chosen artifact's versions — topped up
+/// with Maven Central's (the search endpoint's popular coordinates, the
+/// published version metadata), which the shared version cache keeps for the
+/// session. `None` when the caret is not in a `<dependency>` coordinate element.
+pub async fn maven_dependency_completion(
+    host: &Host,
+    window: &str,
+    doc: DocId,
+    offset: u32,
+    request: RequestId,
+) -> IdeResult<Option<PomCompletion>> {
+    use ide_build::maven::completion::{PomCompletionKind, local_options};
+    let project = host.project(window)?;
+    let cache = host.dependency_versions.clone();
+    let cancel = host.begin_project_read_request(window, request);
+    let result = host
+        .blocking(move || {
+            let snap = project.documents.snapshot(doc)?;
+            if snap.large || snap.read_only || !snap.path.file_name().is_some_and(|name| name == "pom.xml") {
+                return Ok(None);
+            }
+            let Some(target) = ide_build::maven::completion::completion_target(&snap.text, offset) else {
+                return Ok(None);
+            };
+            let settings = project.settings.effective();
+            let repo = ide_sdk::apply::maven_local_repository(&project.root, &settings)
+                .or_else(ide_build::maven::default_local_repo);
+            let mut options = repo.map_or_else(Vec::new, |repo| local_options(&repo, &target));
+            // Central's answers are cached for the session (the shared version cache).
+            // The local repository answers at once: Central gets `CENTRAL_WAIT`, then the
+            // lookup finishes in the background and fills the cache for the next request.
+            // Offline, behind a proxy or rate-limited, a failed fetch never fails completion.
+            let remote = {
+                let (cache, target) = (cache.clone(), target.clone());
+                let (tx, rx) = std::sync::mpsc::channel();
+                std::thread::spawn(move || {
+                    let detached = ide_core::CancellationToken::new();
+                    let found = match target.kind {
+                        PomCompletionKind::GroupId if !target.typed.is_empty() => {
+                            cache.versions(&MavenCentralGroups, &target.typed, &detached).unwrap_or_default()
+                        }
+                        PomCompletionKind::ArtifactId => match &target.group {
+                            Some(group) => cache
+                                .versions(&MavenCentralArtifacts { group: group.clone() }, &target.typed, &detached)
+                                .unwrap_or_default(),
+                            None => Vec::new(),
+                        },
+                        PomCompletionKind::Version => match (&target.group, &target.artifact) {
+                            (Some(group), Some(artifact)) => cache
+                                .versions(&MavenCentralVersions, &format!("{group}:{artifact}"), &detached)
+                                .unwrap_or_default(),
+                            _ => Vec::new(),
+                        },
+                        _ => Vec::new(), // A group id from nothing: the search endpoint has no such query.
+                    };
+                    let _ = tx.send(found);
+                });
+                rx.recv_timeout(CENTRAL_WAIT).unwrap_or_default()
+            };
+            if cancel.is_cancelled() {
+                return Err(IdeError::cancelled());
+            }
+            let known: std::collections::HashSet<String> = options.iter().map(|o| o.label.clone()).collect();
+            options.extend(
+                remote
+                    .into_iter()
+                    .filter(|label| !known.contains(label))
+                    .map(|label| PomCompletionOption { label, detail: None }),
+            );
+            options.truncate(ide_build::maven::completion::MAX_OPTIONS);
+            Ok(Some(PomCompletion { from: target.from, to: target.to, kind: target.kind, options }))
+        })
+        .await;
+    host.end_request(request);
+    result
+}
+
 /// Adds an `<exclusion>` of `exclusion` to the declaration of the direct dependency
 /// `dependency` of the Maven module `pom`, through the open document when there is one
 /// (saved). Returns the declaration; nothing changes when it already excludes it.
@@ -711,6 +810,9 @@ pub(crate) fn register(d: &mut Dispatcher) {
     d.add("maven_goto_declaration", |c| async move {
         maven_goto_declaration(&c.host, &c.window, c.arg("pom")?, c.arg("pos")?).await
     });
+    d.add("maven_dependency_completion", |c| async move {
+        maven_dependency_completion(&c.host, &c.window, c.arg("doc")?, c.arg("offset")?, c.arg("request")?).await
+    });
     d.add("maven_exclude_dependency", |c| async move {
         maven_exclude_dependency(&c.host, &c.window, c.arg("pom")?, c.arg("dependency")?, c.arg("exclusion")?).await
     });
@@ -909,3 +1011,120 @@ mod build_tool_settings_tests {
         assert_eq!(model.env["GRADLE_USER_HOME"], root.join("user-home").to_string_lossy());
     }
 }
+
+#[cfg(test)]
+mod maven_completion_tests {
+    use super::*;
+    use crate::ops::dependencies::hashed_key;
+    use ide_build::maven::completion::PomCompletionKind;
+    use ide_core::CancellationToken;
+    use ide_workspace::dependencies::DependencyVersionSource;
+    use std::sync::Arc;
+
+    /// Cache answers the test plants before completing, so the op's Central
+    /// lookups hit the session cache and the network is never reached.
+    struct FakeSource(&'static str, Vec<&'static str>);
+    impl DependencyVersionSource for FakeSource {
+        fn id(&self) -> &'static str {
+            self.0
+        }
+        fn cache_key(&self, package: &str) -> Option<String> {
+            Some(hashed_key(self.0, package))
+        }
+        fn fetch(&self, _: &str, _: &CancellationToken) -> IdeResult<Vec<String>> {
+            Ok(self.1.iter().map(|s| (*s).to_owned()).collect())
+        }
+    }
+
+    const GROUPS: &str = "maven-central-groups";
+    const ARTIFACTS: &str = "maven-central-artifacts";
+    const VERSIONS: &str = "maven-central-versions";
+
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn completes_dependency_coordinates_from_the_local_repository_then_central() {
+        let temp = tempfile::tempdir().unwrap();
+        let base = dunce::canonicalize(temp.path()).unwrap();
+        let (root, repo) = (base.join("project"), base.join("repository"));
+        std::fs::create_dir_all(&root).unwrap();
+        // Settings › Maven's local repository points at the fixture, so the
+        // test machine's own ~/.m2 is never read.
+        std::fs::create_dir_all(base.join("config")).unwrap();
+        std::fs::write(
+            base.join("config/settings.toml"),
+            format!("[languages.java.maven]\nlocalRepository = \"{}\"\n", repo.to_string_lossy().replace('\\', "/")),
+        )
+        .unwrap();
+        for file in [
+            "org/apache/maven/maven-core/4.0.0-rc-5/maven-core-4.0.0-rc-5.jar",
+            "org/example/lib/2.0/lib-2.0.jar",
+            "org/lib/1.0/lib-1.0.jar",
+        ] {
+            let path = repo.join(file);
+            std::fs::create_dir_all(path.parent().unwrap()).unwrap();
+            std::fs::write(&path, b"").unwrap();
+        }
+        let text = "<project>\n  <dependencies>\n    <dependency>\n      <groupId>org</groupId>\n      <artifactId>lib</artifactId>\n      <version>1.0</version>\n    </dependency>\n    <dependency>\n      <groupId>org.example</groupId>\n      <artifactId></artifactId>\n    </dependency>\n    <dependency>\n      <groupId>org.example</groupId>\n      <artifactId>lib</artifactId>\n      <version></version>\n    </dependency>\n  </dependencies>\n</project>\n";
+        let path = root.join("pom.xml");
+        std::fs::write(&path, text).unwrap();
+
+        let host = Host::new(crate::HostConfig {
+            config_dir: base.join("config"),
+            data_dir: base.join("data"),
+            local_data_dir: base.join("local"),
+            languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+            syntax: Arc::default(),
+            sink_for: Box::new(|_| Arc::new(|_| {})),
+            owner: |w| w,
+            runtime: tokio::runtime::Handle::current(),
+            project_environment: false,
+        });
+        let project = host.open_project("main", &root).unwrap();
+        let info = project.documents.open(&path).unwrap();
+
+        let token = CancellationToken::new();
+        host.dependency_versions.versions(&FakeSource(GROUPS, vec!["org.zzz"]), "org", &token).unwrap();
+        host.dependency_versions.versions(&FakeSource(ARTIFACTS, vec!["api"]), "org.example\u{1}", &token).unwrap();
+        host.dependency_versions.versions(&FakeSource(VERSIONS, vec!["9.9"]), "org.example:lib", &token).unwrap();
+
+        let at = |needle: &str| (text.find(needle).unwrap() + needle.len()) as u32;
+        let next = std::sync::atomic::AtomicU32::new(500);
+        let complete = |offset: u32| {
+            maven_dependency_completion(
+                &host,
+                "main",
+                info.id,
+                offset,
+                RequestId(next.fetch_add(1, std::sync::atomic::Ordering::Relaxed)),
+            )
+        };
+        fn labels(c: &PomCompletion) -> Vec<&str> {
+            c.options.iter().map(|o| o.label.as_str()).collect()
+        }
+
+        let group =
+            complete(text.find("<groupId>org").unwrap() as u32 + "<groupId>org".len() as u32).await.unwrap().unwrap();
+        assert_eq!(group.kind, PomCompletionKind::GroupId);
+        // The installed groups first, Central's cached suggestions behind them.
+        assert_eq!(labels(&group), ["org", "org.apache.maven", "org.example", "org.zzz"]);
+        // Nothing outside a dependency's coordinates.
+        let outside = complete(at("<dependencies>")).await;
+        assert!(matches!(outside, Ok(None)), "{outside:?}");
+
+        let empty_artifact = text.find("<artifactId></artifactId>").unwrap() as u32 + "<artifactId>".len() as u32;
+        let artifact = complete(empty_artifact).await;
+        let artifact = match artifact {
+            Ok(Some(a)) => a,
+            other => panic!("artifact completion: {other:?}"),
+        };
+        assert_eq!(artifact.kind, PomCompletionKind::ArtifactId);
+        let installed = artifact.options.first().unwrap();
+        assert_eq!((installed.label.as_str(), installed.detail.as_deref()), ("lib", Some("2.0")));
+        assert_eq!(labels(&artifact), ["lib", "api"]);
+
+        let empty_version = text.find("<version></version>").unwrap() as u32 + "<version>".len() as u32;
+        let version = complete(empty_version).await.unwrap().unwrap();
+        assert_eq!(version.kind, PomCompletionKind::Version);
+        assert_eq!(labels(&version), ["2.0", "9.9"]);
+        host.close_project("main");
+    }
+}

crates/ide-host/src/ops/dependencies.rs

@@ -1,7 +1,7 @@
 //! Repository version lookups for manifest inspections and completion.
 use crate::{Host, rpc::Dispatcher};
 use ide_core::{CancellationToken, DocId, IdeError, IdeResult, RequestId};
-use ide_workspace::dependencies::{DependencyVersionSource, DependencyVersions, cargo, go, npm};
+use ide_workspace::dependencies::{DependencyVersionSource, DependencyVersions, cargo, go, maven, npm};
 use std::collections::BTreeMap;
 use std::hash::{DefaultHasher, Hash, Hasher};
 use std::path::{Path, PathBuf};
@@ -25,6 +25,79 @@ impl DependencyVersionSource for CratesIo {
     }
 }
 
+/// A cache key for a `package` that is not a filesystem-safe name (a Maven
+/// coordinate with dots, a query): hashed under the source's id.
+pub(crate) fn hashed_key(id: &str, package: &str) -> String {
+    let mut hash = DefaultHasher::new();
+    package.hash(&mut hash);
+    format!("{id}-{:016x}", hash.finish())
+}
+
+/// Maven Central's group-id suggestions: the search endpoint's groups matching
+/// a typed prefix, most recently updated first.
+pub(crate) struct MavenCentralGroups;
+impl DependencyVersionSource for MavenCentralGroups {
+    fn id(&self) -> &'static str {
+        "maven-central-groups"
+    }
+
+    fn cache_key(&self, prefix: &str) -> Option<String> {
+        Some(hashed_key(self.id(), prefix))
+    }
+
+    fn fetch(&self, prefix: &str, cancel: &CancellationToken) -> IdeResult<Vec<String>> {
+        let url = maven::groups_url(prefix).ok_or_else(|| IdeError::internal("invalid group prefix"))?;
+        let search_path = std::env::var_os("PATH").unwrap_or_default();
+        let text =
+            ide_tools::Http::new(&search_path)?.https_only().get_text_limited(&url, Some(1024 * 1024), cancel)?;
+        maven::parse_search_groups(&text).ok_or_else(|| IdeError::internal("invalid search response"))
+    }
+}
+
+/// The artifacts of one group matching a typed prefix, from the same endpoint.
+pub(crate) struct MavenCentralArtifacts {
+    pub group: String,
+}
+impl DependencyVersionSource for MavenCentralArtifacts {
+    fn id(&self) -> &'static str {
+        "maven-central-artifacts"
+    }
+
+    fn cache_key(&self, prefix: &str) -> Option<String> {
+        Some(hashed_key(self.id(), &format!("{}\u{1}{prefix}", self.group)))
+    }
+
+    fn fetch(&self, prefix: &str, cancel: &CancellationToken) -> IdeResult<Vec<String>> {
+        let url =
+            maven::artifacts_url(&self.group, prefix).ok_or_else(|| IdeError::internal("invalid artifact prefix"))?;
+        let search_path = std::env::var_os("PATH").unwrap_or_default();
+        let text =
+            ide_tools::Http::new(&search_path)?.https_only().get_text_limited(&url, Some(1024 * 1024), cancel)?;
+        maven::parse_search_artifacts(&text).ok_or_else(|| IdeError::internal("invalid search response"))
+    }
+}
+
+/// Every version published of one `group:artifact` on Central, newest first.
+pub(crate) struct MavenCentralVersions;
+impl DependencyVersionSource for MavenCentralVersions {
+    fn id(&self) -> &'static str {
+        "maven-central-versions"
+    }
+
+    fn cache_key(&self, coordinates: &str) -> Option<String> {
+        Some(hashed_key(self.id(), coordinates))
+    }
+
+    fn fetch(&self, coordinates: &str, cancel: &CancellationToken) -> IdeResult<Vec<String>> {
+        let (group, artifact) = coordinates.split_once(':').ok_or_else(|| IdeError::internal("invalid coordinates"))?;
+        let url = maven::metadata_url(group, artifact).ok_or_else(|| IdeError::internal("invalid coordinates"))?;
+        let search_path = std::env::var_os("PATH").unwrap_or_default();
+        let text =
+            ide_tools::Http::new(&search_path)?.https_only().get_text_limited(&url, Some(2 * 1024 * 1024), cancel)?;
+        Ok(maven::parse_metadata_versions(&text))
+    }
+}
+
 struct NpmRegistry;
 impl DependencyVersionSource for NpmRegistry {
     fn id(&self) -> &'static str {

crates/ide-host/src/ops/fs.rs

@@ -114,14 +114,28 @@ pub fn create_file(host: &Host, window: &str, path: PathBuf) -> IdeResult<()> {
             if empty && !bom.is_empty() {
                 std::fs::write(&path, bom)?;
             }
+            // A checkout backend opens the file for add; Git's hook is a no-op.
+            if let Err(e) = p.with_backend_of(&path, |r| r.files_added(std::slice::from_ref(&path))) {
+                tracing::debug!("vcs files_added for {}: {e}", path.display());
+            }
             Ok(())
         }
         Err(_) => ide_vfs::create_file(&path),
     }
 }
 
-pub async fn create_file_bytes(host: &Host, path: PathBuf, data: Vec<u8>) -> IdeResult<()> {
-    host.blocking(move || ide_vfs::create_file_bytes(&path, &data)).await
+pub async fn create_file_bytes(host: &Host, window: &str, path: PathBuf, data: Vec<u8>) -> IdeResult<()> {
+    let project = host.project(window).ok();
+    host.blocking(move || {
+        ide_vfs::create_file_bytes(&path, &data)?;
+        if let Some(p) = project
+            && let Err(e) = p.with_backend_of(&path, |r| r.files_added(std::slice::from_ref(&path)))
+        {
+            tracing::debug!("vcs files_added for {}: {e}", path.display());
+        }
+        Ok(())
+    })
+    .await
 }
 
 /// Toggle Read-only Attribute: sets the writable bit (and the open document's
@@ -135,25 +149,54 @@ pub fn set_writable(host: &Host, window: &str, path: PathBuf, writable: bool) ->
 
 /// Moves to the trash; Local History keeps the contents so deleted files can be restored.
 pub async fn delete(host: &Host, window: &str, path: PathBuf) -> IdeResult<()> {
-    let history = host.project(window).ok().map(|p| p.history.clone());
+    let project = host.project(window).ok();
+    let history = project.as_ref().map(|p| p.history.clone());
     host.blocking(move || {
         let paths = ide_workspace::file_ops::deletion_paths(&path)?;
         if let Some(h) = history {
-            for p in paths {
-                h.record_deletion(&p, DELETE_SNAPSHOT_LIMIT);
+            for p in &paths {
+                h.record_deletion(p, DELETE_SNAPSHOT_LIMIT);
             }
         }
-        ide_workspace::file_ops::delete(&path)
+        ide_workspace::file_ops::delete(&path)?;
+        // A checkout backend opens the paths for delete; Git's hook is a no-op.
+        if let Some(p) = project {
+            let _ = p.with_backend_of(&path, |r| r.files_deleted(&paths));
+        }
+        Ok(())
     })
     .await
 }
 
-pub async fn copy(host: &Host, from: PathBuf, to: PathBuf) -> IdeResult<()> {
-    host.blocking(move || ide_workspace::file_ops::copy(&from, &to)).await
+pub async fn copy(host: &Host, window: &str, from: PathBuf, to: PathBuf) -> IdeResult<()> {
+    let project = host.project(window).ok();
+    host.blocking(move || {
+        ide_workspace::file_ops::copy(&from, &to)?;
+        // A copy is an add at the destination; Git's hook is a no-op.
+        if let Some(p) = project
+            && let Err(e) = p.with_backend_of(&to, |r| r.files_added(std::slice::from_ref(&to)))
+        {
+            tracing::debug!("vcs files_added for {}: {e}", to.display());
+        }
+        Ok(())
+    })
+    .await
 }
 
-pub async fn rename(host: &Host, from: PathBuf, to: PathBuf) -> IdeResult<()> {
-    host.blocking(move || ide_workspace::file_ops::rename(&from, &to)).await
+pub async fn rename(host: &Host, window: &str, from: PathBuf, to: PathBuf) -> IdeResult<()> {
+    let project = host.project(window).ok();
+    host.blocking(move || {
+        ide_workspace::file_ops::rename(&from, &to)?;
+        // A checkout backend records the rename so history follows the file;
+        // Git's hook is a no-op.
+        if let Some(p) = project
+            && let Err(e) = p.with_backend_of(&to, |r| r.file_moved(&from, &to))
+        {
+            tracing::debug!("vcs file_moved {} → {}: {e}", from.display(), to.display());
+        }
+        Ok(())
+    })
+    .await
 }
 
 /// Reads a text file without opening it as a document; prefers the unsaved buffer.

crates/ide-host/src/ops/java.rs

@@ -48,7 +48,7 @@ async fn resolve_launch(
     let build = policy != BuildPolicy::NoBuild;
     let full = policy == BuildPolicy::Rebuild;
     let build_kind = if full { compile::BuildKind::Rebuild } else { compile::BuildKind::Build };
-    let (model, external, delegated, prefer_maven) = {
+    let (model, external, mut delegated, prefer_maven, is_maven) = {
         let project = project.clone();
         let settings = settings.clone();
         let module = module.clone();
@@ -68,13 +68,29 @@ async fn resolve_launch(
                     prefer_maven,
                 );
             let external = non_java || delegated;
-            (model, external, delegated, prefer_maven)
+            (model, external, delegated, prefer_maven, is_maven)
         })
         .await
         .map_err(|e| IdeError::internal(e.to_string()))?
     };
-    let external_build = if delegated { Some(project.lsp.java_external_build(&module, cancel).await?) } else { None };
+    let mut external_build =
+        if delegated { Some(project.lsp.java_external_build(&module, cancel).await?) } else { None };
     let mut info = project.lsp.java_launch(&module, test, build && !delegated, full, delegated, cancel).await?;
+    if info.errors.iter().any(|e| processor_recreated_a_file(&e.message)) {
+        if build && !delegated && is_maven {
+            // JDT runs an annotation processor again over sources it generated in the same build
+            // (MapStruct over MapStruct-Plus's mappers) and fails on the file it already wrote;
+            // javac doesn't, so Maven builds the module.
+            tracing::info!("Annotation processing failed in JDT; building with Maven");
+            delegated = true;
+            external_build = Some(project.lsp.java_external_build(&module, cancel).await?);
+            info = project.lsp.java_launch(&module, test, false, false, true, cancel).await?;
+        }
+        if delegated {
+            // Maven runs the annotation processors itself; JDT's failure to rerun one is no compile error.
+            drop_processor_recreate_errors(&mut info);
+        }
+    }
     let lsp_ms = started.elapsed().as_millis();
     let data_dir = host.local_data_dir.clone();
     let cancel = cancel.clone();
@@ -338,10 +354,60 @@ pub(crate) fn register(d: &mut Dispatcher) {
     });
 }
 
+/// An annotation processor's error for writing a file this build already wrote (JDT's
+/// `IdeFilerImpl`: "Source file already created", javac's Filer: "Attempt to recreate a file").
+fn processor_recreated_a_file(message: &str) -> bool {
+    message.contains("FilerException")
+        && (message.contains("Source file already created") || message.contains("Attempt to recreate a file"))
+}
+
+fn drop_processor_recreate_errors(info: &mut JavaLaunchInfo) {
+    let before = info.errors.len();
+    info.errors.retain(|e| !processor_recreated_a_file(&e.message));
+    info.error_count = info.error_count.saturating_sub((before - info.errors.len()) as u32);
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
 
+    #[test]
+    fn recognises_a_processor_recreating_its_output() {
+        assert!(processor_recreated_a_file(
+            "Internal error in the mapping processor: java.lang.RuntimeException: \
+             javax.annotation.processing.FilerException: Source file already created: /m/target/generated-sources/annotations/a/AMapper__4Impl.java"
+        ));
+        assert!(processor_recreated_a_file(
+            "javax.annotation.processing.FilerException: Attempt to recreate a file for type a.B"
+        ));
+        assert!(!processor_recreated_a_file("Source file already created"));
+        assert!(!processor_recreated_a_file("cannot find symbol"));
+    }
+
+    #[test]
+    fn a_delegated_launch_ignores_jdt_processor_recreate_errors() {
+        let error = |message: &str| ide_lsp::jdtls::JavaCompileError {
+            path: "src/main/java/a/A.java".into(),
+            line: 1,
+            column: 1,
+            message: message.into(),
+        };
+        let mut info = JavaLaunchInfo {
+            error_count: 2,
+            errors: vec![
+                error(
+                    "javax.annotation.processing.FilerException: Source file already created: /m/AMapper__1Impl.java",
+                ),
+                error("cannot find symbol"),
+            ],
+            ..Default::default()
+        };
+        drop_processor_recreate_errors(&mut info);
+        assert_eq!(info.error_count, 1);
+        assert_eq!(info.errors.len(), 1);
+        assert_eq!(info.errors[0].message, "cannot find symbol");
+    }
+
     #[test]
     fn delegated_launches_with_jdt_errors_recompile_with_maven() {
         assert_eq!(delegated_policy(BuildPolicy::Make, true, 1), BuildPolicy::Rebuild);

crates/ide-host/src/ops/run.rs

@@ -234,7 +234,19 @@ pub async fn start_request(
 ) -> IdeResult<RunInfo> {
     let cancel = request.map(|id| host.begin_request(id)).unwrap_or_default();
     let operation = config.extras.params.get("plugin.operation").cloned();
-    let result = start_inner(host, window, config, on_output, &cancel).await;
+    let mut config = config;
+    let agent = match host.project(window) {
+        Ok(project) => host.mcp_agent_runs.launch(&project.root, window, &mut config),
+        Err(_) => None,
+    };
+    let on_output = match &agent {
+        Some(agent) => agent.wrap_output(on_output),
+        None => on_output,
+    };
+    let result = start_inner(host, window, config, on_output, agent.as_ref(), &cancel).await;
+    if let Some(agent) = &agent {
+        agent.started(&result);
+    }
     if let Some(id) = request {
         host.end_request(id);
     }
@@ -249,6 +261,7 @@ async fn start_inner(
     window: &str,
     mut config: RunConfig,
     on_output: Emit<OutputChunk>,
+    agent: Option<&crate::mcp::run::agent::Launch>,
     cancel: &ide_core::CancellationToken,
 ) -> IdeResult<RunInfo> {
     if cancel.is_cancelled() {
@@ -282,6 +295,9 @@ async fn start_inner(
     if let Some(plugins) = host.plugin_host() {
         sink = plugins.run_operation_sink(window, &mut config, sink)?;
     }
+    if let Some(agent) = agent {
+        sink = agent.wrap_sink(sink);
+    }
     if config.command.is_empty() {
         return Err(IdeError::invalid("run configuration has no command"));
     }
@@ -450,6 +466,7 @@ pub fn stop(host: &Host, window: &str, id: RunId) -> IdeResult<()> {
     if let Some(plugins) = host.plugin_host() {
         plugins.run_operation_stopped(id);
     }
+    host.mcp_agent_runs.stopping(id);
     let settings = match host.project(window) {
         Ok(p) => p.settings.effective(),
         Err(_) => host.global_settings.effective(),
@@ -461,7 +478,9 @@ pub fn stop(host: &Host, window: &str, id: RunId) -> IdeResult<()> {
     host.processes.stop_with_grace(id, grace)
 }
 
+/// Input the user typed into a run (the agent's goes to the process directly).
 pub fn stdin(host: &Host, id: RunId, data: &str) -> IdeResult<()> {
+    host.mcp_agent_runs.user_input(id, data);
     if host.remote.runs.contains(id) {
         return host.remote.runs.write_stdin(id, data);
     }

crates/ide-host/src/ops/sdk.rs

@@ -7,6 +7,8 @@ use ide_core::{IdeError, IdeResult, RequestId};
 use ide_sdk::python::PythonPackage;
 use ide_sdk::{Sdk, SdkKind};
 use std::path::PathBuf;
+use std::sync::Mutex;
+use std::sync::atomic::{AtomicUsize, Ordering};
 
 fn join_err(e: impl std::fmt::Display) -> IdeError {
     IdeError::internal(e.to_string())
@@ -20,6 +22,14 @@ pub struct LocatedTools {
     pub compile_dir: ide_core::IpcPath,
 }
 
+/// An interpreter another project uses: the project root and the SDK itself.
+#[derive(Clone, Debug, serde::Serialize, specta::Type)]
+#[serde(rename_all = "camelCase")]
+pub struct ProjectInterpreter {
+    pub project: ide_core::IpcPath,
+    pub sdk: Sdk,
+}
+
 /// Installed interpreters / toolchains of `kind`; project-local ones first.
 pub async fn sdk_detect(host: &Host, window: &str, kind: SdkKind) -> IdeResult<Vec<Sdk>> {
     host.require_trust(window)?;
@@ -45,6 +55,50 @@ pub async fn sdk_detect(host: &Host, window: &str, kind: SdkKind) -> IdeResult<V
     .map_err(join_err)
 }
 
+/// The Python interpreters of the projects opened recently (newest first), each with the
+/// project it belongs to. The open project is skipped: [`sdk_detect`] lists its own.
+pub async fn sdk_python_project_interpreters(host: &Host, window: &str) -> IdeResult<Vec<ProjectInterpreter>> {
+    host.require_trust(window)?;
+    let current = host.project(window).ok().map(|p| p.root.clone());
+    let config = host.config_dir.clone();
+    tokio::task::spawn_blocking(move || {
+        let roots: Vec<PathBuf> = ide_workspace::RecentProjects::load(&config)
+            .list()
+            .into_iter()
+            .map(|p| p.path.into_path_buf())
+            .filter(|root| current.as_deref() != Some(root.as_path()))
+            .collect();
+        // Each project resolves its configured interpreter, else its own virtualenv. The
+        // probes run `python`, so keep them off the async runtime and bound how many run at
+        // once: the recent list can hold ~30 projects, and each probe starts a process.
+        const PROBES: usize = 4;
+        let results = Mutex::new(Vec::with_capacity(roots.len()));
+        let next = AtomicUsize::new(0);
+        std::thread::scope(|scope| {
+            for _ in 0..roots.len().min(PROBES) {
+                scope.spawn(|| {
+                    loop {
+                        let index = next.fetch_add(1, Ordering::Relaxed);
+                        let Some(root) = roots.get(index) else { break };
+                        let settings = ide_workspace::SettingsStore::load(&config, Some(root)).effective();
+                        let Some(python) = ide_sdk::apply::python_interpreter(root, &settings) else { continue };
+                        let Some(sdk) = ide_sdk::python_interpreter_sdk(&python, Some(root)) else { continue };
+                        results
+                            .lock()
+                            .unwrap()
+                            .push((index, ProjectInterpreter { project: root.as_path().into(), sdk }));
+                    }
+                });
+            }
+        });
+        let mut found = results.into_inner().unwrap();
+        found.sort_by_key(|(index, _)| *index);
+        found.into_iter().map(|(_, interpreter)| interpreter).collect()
+    })
+    .await
+    .map_err(join_err)
+}
+
 /// An existing Python executable or virtualenv folder as an SDK; `None` if Python cannot run.
 pub async fn sdk_python_interpreter(host: &Host, window: &str, path: PathBuf) -> IdeResult<Option<Sdk>> {
     host.require_trust(window)?;
@@ -310,6 +364,10 @@ pub async fn sdk_python_pip(
 /// Commands of this module the remote server answers.
 pub(crate) fn register(d: &mut Dispatcher) {
     d.add("sdk_detect", |c| async move { sdk_detect(&c.host, &c.window, c.arg("kind")?).await });
+    d.add(
+        "sdk_python_project_interpreters",
+        |c| async move { sdk_python_project_interpreters(&c.host, &c.window).await },
+    );
     d.add(
         "sdk_python_interpreter",
         |c| async move { sdk_python_interpreter(&c.host, &c.window, c.arg("path")?).await },
@@ -425,4 +483,49 @@ mod tests {
         assert!(sdk_python_interpreter(&host, "main", root.join("README.md")).await.unwrap().is_none());
         host.close_project("main");
     }
+
+    #[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+    async fn another_projects_interpreter_is_listed_with_its_project() {
+        let temp = tempfile::tempdir().unwrap();
+        let base = dunce::canonicalize(temp.path()).unwrap();
+        let root = base.join("project");
+        let other = base.join("shop");
+        std::fs::create_dir_all(other.join(".openidea")).unwrap();
+        std::fs::create_dir_all(&root).unwrap();
+        let python = fake_venv(&other, ".venv");
+        std::fs::write(
+            other.join(".openidea/settings.toml"),
+            "[languages.python]\ninterpreter = \".venv/bin/python\"\n",
+        )
+        .unwrap();
+        // The projects the user opened before this one.
+        let config = base.join("config");
+        std::fs::create_dir_all(&config).unwrap();
+        let recent = serde_json::json!([
+            { "path": other.to_str().unwrap(), "name": "shop", "openedAtMs": 2.0, "branch": null },
+            { "path": root.to_str().unwrap(), "name": "project", "openedAtMs": 1.0, "branch": null },
+        ]);
+        std::fs::write(config.join("recent.json"), serde_json::to_vec(&recent).unwrap()).unwrap();
+
+        let host = Host::new(HostConfig {
+            config_dir: config,
+            data_dir: base.join("data"),
+            local_data_dir: base.join("local"),
+            languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+            syntax: Arc::default(),
+            sink_for: Box::new(|_| Arc::new(|_| {})),
+            owner: |w| w,
+            runtime: tokio::runtime::Handle::current(),
+            project_environment: false,
+        });
+        host.trust.decide(&root, true, false).unwrap();
+        host.open_project("main", &root).unwrap();
+
+        let list = sdk_python_project_interpreters(&host, "main").await.unwrap();
+        assert_eq!(list.len(), 1, "{list:?}");
+        assert_eq!(&*list[0].project, other.as_path());
+        assert_eq!(&*list[0].sdk.path, python.as_path());
+        assert_eq!(list[0].sdk.name, "Python 3.12 (shop)");
+        host.close_project("main");
+    }
 }

crates/ide-host/src/ops/vcs/commands.rs

@@ -138,6 +138,11 @@ impl LogAccess {
             .ok_or_else(|| ide_core::IdeError::unavailable("external Git log is not open"))?
             .with_log_repo_at(at, f)
     }
+
+    /// `with_log_repo_at` through the backend-agnostic Changes-view surface.
+    fn with_log_backend_at<T>(&self, at: Option<&Path>, f: impl FnOnce(&dyn Backend) -> IdeResult<T>) -> IdeResult<T> {
+        self.with_log_repo_at(at, |r| f(r as &dyn Backend))
+    }
 }
 
 /// A repository of the project (IDEA's VCS root).
@@ -280,6 +285,16 @@ fn per_repo(
     Ok(())
 }
 
+/// `per_repo` through the backend-agnostic Changes-view surface.
+fn per_backend(
+    project: &Project,
+    paths: &[PathBuf],
+    recorded: Option<&str>,
+    f: impl Fn(&dyn Backend, &[PathBuf]) -> IdeResult<()>,
+) -> IdeResult<()> {
+    per_repo(project, paths, recorded, |r, paths| f(r as &dyn Backend, paths))
+}
+
 /// A shelf is one patch for one owning repository. Validate the whole selection before reverting files.
 fn shelf_repository(project: &Project, paths: &[PathBuf]) -> IdeResult<PathBuf> {
     let repos = project.repos();
@@ -348,7 +363,7 @@ pub async fn vcs_line_hunks(host: &Host, window: &str, path: PathBuf) -> IdeResu
     let project = host.project(window)?;
     blocking(move || {
         let text = project.text_of(&path)?;
-        project.with_repo_of(&path, |r| r.line_hunks(&path, &text, false, project.vcs_encoding(&path, None)?))
+        project.with_backend_of(&path, |r| r.line_hunks(&path, &text, false, project.vcs_encoding(&path, None)?))
     })
     .await
 }
@@ -360,7 +375,7 @@ pub async fn vcs_file_at(host: &Host, window: &str, path: PathBuf, rev: Option<S
     });
     blocking(move || {
         if let Some(project) = project {
-            return project.with_log_repo_of(&path, |r| {
+            return project.with_log_backend_of(&path, |r| {
                 r.file_at(&path, rev.as_deref(), project.vcs_encoding(&path, rev.as_deref())?)
             });
         }
@@ -383,7 +398,7 @@ pub async fn vcs_file_mode(host: &Host, window: &str, path: PathBuf, rev: Option
     });
     blocking(move || {
         if let Some(project) = project {
-            return project.with_log_repo_of(&path, |r| r.file_mode_at(&path, rev.as_deref()));
+            return project.with_log_backend_of(&path, |r| r.file_mode_at(&path, rev.as_deref()));
         }
         external
             .ok_or_else(|| ide_core::IdeError::unavailable("external Git log is not open"))?
@@ -403,7 +418,7 @@ pub async fn vcs_blame(
     // An explicit text wins (merge view annotates its side panes, not the worktree).
     blocking(move || {
         let text = text.or_else(|| project.documents.text_of(&path));
-        project.with_repo_of(&path, |r| {
+        project.with_backend_of(&path, |r| {
             r.blame(&path, text.as_deref(), revision.as_deref(), project.vcs_encoding(&path, revision.as_deref())?)
         })
     })
@@ -424,7 +439,7 @@ pub async fn vcs_block_history(
     let cancel = host.begin_request(request);
     let result = blocking(move || {
         let text = text.or_else(|| project.documents.text_of(&path));
-        project.with_repo_of(&path, |r| {
+        project.with_backend_of(&path, |r| {
             r.block_history(&path, text.as_deref(), lines, project.vcs_encoding(&path, None)?, &cancel)
         })
     })
@@ -441,7 +456,7 @@ pub async fn vcs_log(host: &Host, window: &str, repo: Option<PathBuf>, query: Lo
     let result = blocking(move || {
         project.with_log_repo_at(repo.as_deref(), |r| {
             r.enable_log_index(&project.cache);
-            r.log_cancellable(&query, &cancel)
+            (r as &dyn Backend).log(&query, &cancel)
         })
     })
     .await;
@@ -540,7 +555,7 @@ pub async fn vcs_commit_files(
     commit: String,
 ) -> IdeResult<Vec<ChangedFile>> {
     let project = LogAccess::new(host, window, repo.as_deref());
-    blocking(move || project.with_log_repo_at(repo.as_deref(), |r| r.commit_files(&commit))).await
+    blocking(move || project.with_log_backend_at(repo.as_deref(), |r| r.commit_files(&commit))).await
 }
 
 /// Combined changes of several commits, `commits` oldest first.
@@ -551,7 +566,7 @@ pub async fn vcs_commits_changes(
     commits: Vec<String>,
 ) -> IdeResult<Vec<RevisionChange>> {
     let project = LogAccess::new(host, window, repo.as_deref());
-    blocking(move || project.with_log_repo_at(repo.as_deref(), |r| r.commits_changes(&commits))).await
+    blocking(move || project.with_log_backend_at(repo.as_deref(), |r| r.commits_changes(&commits))).await
 }
 
 pub async fn vcs_branches(host: &Host, window: &str, repo: Option<PathBuf>) -> IdeResult<Vec<Branch>> {
@@ -567,7 +582,7 @@ pub async fn vcs_stashes(host: &Host, window: &str, repo: Option<PathBuf>) -> Id
 pub async fn vcs_stage(host: &Host, window: &str, paths: Vec<PathBuf>) -> IdeResult<()> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    blocking(move || per_repo(&project, &paths, None, |r, paths| r.stage(paths))).await
+    blocking(move || per_backend(&project, &paths, None, |r, paths| r.stage(paths))).await
 }
 
 /// Project-host operation (also registered with the remote dispatcher).
@@ -602,7 +617,7 @@ pub async fn vcs_add_to_ignore(
 pub async fn vcs_unstage(host: &Host, window: &str, paths: Vec<PathBuf>) -> IdeResult<()> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    blocking(move || per_repo(&project, &paths, None, |r, paths| r.unstage(paths))).await
+    blocking(move || per_backend(&project, &paths, None, |r, paths| r.unstage(paths))).await
 }
 
 pub async fn vcs_stage_patch(host: &Host, window: &str, patch: String) -> IdeResult<()> {
@@ -614,7 +629,7 @@ pub async fn vcs_stage_patch(host: &Host, window: &str, patch: String) -> IdeRes
 pub async fn vcs_discard(host: &Host, window: &str, paths: Vec<PathBuf>) -> IdeResult<()> {
     host.require_trust(window)?;
     let project = host.project(window)?;
-    blocking(move || per_repo(&project, &paths, Some("Rollback"), |r, paths| r.discard(paths))).await
+    blocking(move || per_backend(&project, &paths, Some("Rollback"), |r, paths| r.discard(paths))).await
 }
 
 pub async fn vcs_commit(
@@ -628,8 +643,8 @@ pub async fn vcs_commit(
     // Commit hooks may run for a long time.
     let project = host.project(window)?;
     blocking(move || {
-        project.with_repo_recorded(repo.as_deref(), None, |r| {
-            r.commit_with(&message, &options, &|path| project.vcs_encoding(path, None))
+        project.with_backend_recorded(repo.as_deref(), None, |r| {
+            r.commit(&message, &options, &|path| project.vcs_encoding(path, None))
         })
     })
     .await
@@ -886,7 +901,7 @@ pub async fn vcs_conflict_versions(host: &Host, window: &str, path: PathBuf) ->
 
 pub async fn vcs_diff_text(host: &Host, window: &str, path: PathBuf, staged: bool) -> IdeResult<String> {
     let project = host.project(window)?;
-    blocking(move || project.with_repo_of(&path, |r| r.diff_text(&path, staged, project.vcs_encoding(&path, None)?)))
+    blocking(move || project.with_backend_of(&path, |r| r.diff_text(&path, staged, project.vcs_encoding(&path, None)?)))
         .await
 }
 
@@ -1201,7 +1216,7 @@ pub async fn vcs_diff_with_worktree(
     rev: String,
 ) -> IdeResult<Vec<ChangedFile>> {
     let project = LogAccess::new(host, window, repo.as_deref());
-    blocking(move || project.with_log_repo_at(repo.as_deref(), |r| r.diff_with_worktree(&rev))).await
+    blocking(move || project.with_log_backend_at(repo.as_deref(), |r| r.diff_with_worktree(&rev))).await
 }
 
 /// Files that differ between two revisions (the "N files updated" of Update Project).
@@ -1213,7 +1228,7 @@ pub async fn vcs_diff_revisions(
     to: String,
 ) -> IdeResult<Vec<ChangedFile>> {
     let project = LogAccess::new(host, window, repo.as_deref());
-    blocking(move || project.with_log_repo_at(repo.as_deref(), |r| r.diff_revisions(&from, &to))).await
+    blocking(move || project.with_log_backend_at(repo.as_deref(), |r| r.diff_revisions(&from, &to))).await
 }
 
 /// Added and deleted lines between two revisions. `paths` limits the diff; empty diffs every file.

crates/ide-host/src/plugins/api.rs

@@ -179,7 +179,7 @@ impl SecretStore for FileSecretStore {
 }
 
 /// Largest response body a plugin receives.
-const MAX_RESPONSE: usize = 8 << 20;
+const MAX_RESPONSE: usize = 16 << 20;
 /// Largest stdout / stderr kept from a process.
 const MAX_OUTPUT: usize = 16 << 20;
 /// Most processes one plugin keeps running at once.
@@ -1276,12 +1276,13 @@ pub(super) fn commit_draft(
         };
         // Both callers have checked that the window's project is trusted.
         r.set_execution_allowed(true);
-        let pending = r.pending_changes(&repo.options, budget, &|path| Ok(workspace.vcs_encoding(path))).map_err(
-            |e| match e.kind {
+        let backend = &r as &dyn ide_vcs::Backend;
+        let pending = backend
+            .pending_changes(&repo.options, budget, &|path| Ok(workspace.vcs_encoding(path)))
+            .map_err(|e| match e.kind {
                 ide_core::error::ErrorKind::InvalidInput => HostError::Invalid(e.message),
                 _ => HostError::Failed(e.message),
-            },
-        )?;
+            })?;
         let root = to_ipc(r.root());
         for c in pending {
             budget -= c.diff.as_ref().map_or(0, String::len).min(budget);
@@ -1530,6 +1531,19 @@ impl HostApi for PluginApi {
         }
         Ok(())
     }
+    fn open_diff(
+        &self,
+        client: &str,
+        diff: ide_plugin::ContentDiff,
+        file_name: Option<String>,
+    ) -> Result<(), HostError> {
+        super::execution::validate_diff(&diff)?;
+        if let Some(name) = &file_name {
+            super::execution::label(name, 256)?;
+        }
+        self.shared.sink.emit(Some(client), PluginEvent::OpenDiff { plugin_id: self.id().into(), diff, file_name });
+        Ok(())
+    }
     fn reply_content_tab(
         &self,
         client: &str,
@@ -2267,7 +2281,7 @@ impl HostApi for PluginApi {
                 let mut response = response;
                 while let Some(chunk) = response.chunk().await.map_err(|e| HostError::Failed(e.to_string()))? {
                     if body.len() + chunk.len() > MAX_RESPONSE {
-                        return Err(HostError::Failed("response larger than 8 MiB".into()));
+                        return Err(HostError::Failed(format!("response larger than {} MiB", MAX_RESPONSE >> 20)));
                     }
                     body.extend_from_slice(&chunk);
                 }
@@ -3949,6 +3963,72 @@ mod tests {
         worker.join().unwrap();
     }
 
+    #[test]
+    fn fetch_accepts_responses_up_to_16_mib_and_rejects_larger_bodies() {
+        fn serve_bytes(total: usize) -> (u16, std::thread::JoinHandle<()>) {
+            let listener = std::net::TcpListener::bind("127.0.0.1:0").unwrap();
+            let port = listener.local_addr().unwrap().port();
+            let handle = std::thread::spawn(move || {
+                use std::io::{Read, Write};
+                let (mut stream, _) = listener.accept().unwrap();
+                let mut buf = [0; 4096];
+                let _ = stream.read(&mut buf);
+                let header = format!("HTTP/1.1 200 OK\r\nContent-Length: {total}\r\nConnection: close\r\n\r\n");
+                if stream.write_all(header.as_bytes()).is_err() {
+                    return;
+                }
+                let chunk = [b'x'; 64 << 10];
+                let mut sent = 0;
+                while sent < total {
+                    let n = (total - sent).min(chunk.len());
+                    if stream.write_all(&chunk[..n]).is_err() {
+                        break;
+                    }
+                    sent += n;
+                }
+            });
+            (port, handle)
+        }
+
+        let dir = tempfile::tempdir().unwrap();
+        let api = api(dir.path(), Arc::default());
+
+        let (ok_port, ok_worker) = serve_bytes(10 << 20);
+        let resp = api
+            .fetch(
+                HttpRequest {
+                    method: "GET".into(),
+                    url: format!("http://127.0.0.1:{ok_port}/"),
+                    headers: Vec::new(),
+                    body: None,
+                    timeout: Duration::from_secs(10),
+                    grants: vec![Capability::Net("127.0.0.1".into())],
+                },
+                &CancellationToken::new(),
+            )
+            .expect("10 MiB response within 16 MiB limit succeeds");
+        assert_eq!(resp.status, 200);
+        assert_eq!(resp.body.len(), 10 << 20);
+        ok_worker.join().unwrap();
+
+        let (big_port, big_worker) = serve_bytes(MAX_RESPONSE + (1 << 20));
+        let err = api
+            .fetch(
+                HttpRequest {
+                    method: "GET".into(),
+                    url: format!("http://127.0.0.1:{big_port}/"),
+                    headers: Vec::new(),
+                    body: None,
+                    timeout: Duration::from_secs(10),
+                    grants: vec![Capability::Net("127.0.0.1".into())],
+                },
+                &CancellationToken::new(),
+            )
+            .expect_err("response exceeding 16 MiB fails explicitly");
+        assert!(matches!(&err, HostError::Failed(msg) if msg.contains("response larger than 16 MiB")), "{err:?}");
+        big_worker.join().unwrap();
+    }
+
     #[test]
     fn output_ring_keeps_utf8_and_is_withdrawn_on_stop() {
         let dir = tempfile::tempdir().unwrap();

crates/ide-host/src/plugins/execution.rs

@@ -72,14 +72,19 @@ pub(super) fn validate_reply(reply: &ContentTabReply) -> Result<(), HostError> {
         return Err(HostError::Invalid("content status or error too long".into()));
     }
     if let Some(diff) = &reply.diff {
-        body(&diff.left)?;
-        body(&diff.right)?;
-        for value in [&diff.left_label, &diff.right_label].into_iter().flatten() {
-            label(value, 128)?;
-        }
-        if let Some(title) = &diff.title {
-            label(title, 256)?;
-        }
+        validate_diff(diff)?;
+    }
+    Ok(())
+}
+
+pub(super) fn validate_diff(diff: &ide_plugin::ContentDiff) -> Result<(), HostError> {
+    body(&diff.left)?;
+    body(&diff.right)?;
+    for value in [&diff.left_label, &diff.right_label].into_iter().flatten() {
+        label(value, 128)?;
+    }
+    if let Some(title) = &diff.title {
+        label(title, 256)?;
     }
     Ok(())
 }

crates/ide-host/src/plugins/remote_host.rs

@@ -47,6 +47,48 @@ pub const SECRET_REQUEST: &str = "plugin_secret";
 pub const SECRET_WRITE: &str = "plugin_secret_write";
 /// OAuth listeners bound on the desktop, never the project server.
 pub const AUTH_REQUEST: &str = "plugin_auth";
+/// What [`RemotePlugins::register`] adds to a server's commands.
+pub const COMMANDS: &[&str] = &[
+    SYNC_PACKAGES,
+    "plugin_run_command",
+    "plugin_set_ui_locale",
+    "plugin_select_tests",
+    "plugin_parse_test_results",
+    "plugin_terminal_session_close",
+    "plugin_terminal_session_spawn",
+    "plugin_prepare_debug_run",
+    "plugin_finish_operation",
+    "plugin_content_tab_action",
+    "plugin_post_events",
+    "plugin_event_kinds",
+    "plugin_status_items",
+    "plugin_context_keys",
+    "plugin_cancel_task",
+    "plugin_answer_prompt",
+    "plugin_choose_program",
+    "plugin_program",
+    "plugin_answer_command",
+    "plugin_answer_commit",
+    "plugin_commit_checks",
+    "mcp_set_open_editors",
+    "mcp_set_focused_editor",
+    "mcp_report_problems",
+    "plugin_decoration_sets",
+    "plugin_set_active_file",
+    "plugin_view_render",
+    "plugin_view_event",
+    "plugin_service_detail",
+    "plugin_service_log",
+    "plugin_navigation_files",
+    "plugin_navigation_invalidate",
+    "plugin_navigation_index",
+    "plugin_navigation_goto",
+    "plugin_navigation_markers",
+    "plugin_endpoints",
+    "plugin_run_targets",
+    "plugin_answer_run_target",
+    "plugin_line_markers",
+];
 
 #[derive(Clone, Serialize, Deserialize)]
 pub struct SecretWrite {
@@ -134,20 +176,25 @@ pub fn package_digest(dir: &Path, files: &[PathBuf]) -> IdeResult<String> {
 }
 
 /// Whether a plugin event means something to a remote window (the desktop
-/// owns the plugin list, themes and consent).
+/// owns the plugin list, themes and consent). The desktop checks it again on
+/// arrival: a server may send anything, and only what acts on the remote project
+/// passes. A command may only be another plugin command, which runs on the server.
 pub fn forwarded(event: &PluginEvent) -> bool {
+    if let PluginEvent::ExecuteCommand { id, .. } = event {
+        return plugin_command(id);
+    }
     matches!(
         event,
         PluginEvent::RunTargetsChanged
             | PluginEvent::WindowRequest { .. }
             | PluginEvent::ContentTabReply { .. }
+            | PluginEvent::OpenDiff { .. }
             | PluginEvent::DecorationsChanged { .. }
             | PluginEvent::EditorOpen { .. }
             | PluginEvent::EditorRanges { .. }
             | PluginEvent::Notification { .. }
             | PluginEvent::StatusItemChanged { .. }
             | PluginEvent::WindowStatusItemChanged { .. }
-            | PluginEvent::ExecuteCommand { .. }
             | PluginEvent::OutputChanged { .. }
             | PluginEvent::RevealOutput { .. }
             | PluginEvent::ContextChanged { .. }
@@ -163,7 +210,6 @@ pub fn forwarded(event: &PluginEvent) -> bool {
             | PluginEvent::OpenLogTab { .. }
             | PluginEvent::CopyToClipboard { .. }
             | PluginEvent::OpenUrl { .. }
-            | PluginEvent::OpenProject { .. }
             | PluginEvent::PromptRequested { .. }
             | PluginEvent::PromptClosed { .. }
             | PluginEvent::PromptWaiting { .. }
@@ -173,6 +219,13 @@ pub fn forwarded(event: &PluginEvent) -> bool {
     )
 }
 
+/// `plugin.<plugin id>.<command id>`, as the workbench names plugin commands.
+fn plugin_command(id: &str) -> bool {
+    id.strip_prefix("plugin.")
+        .and_then(|rest| rest.split_once('.'))
+        .is_some_and(|(plugin, command)| !plugin.is_empty() && !command.is_empty() && !command.ends_with('.'))
+}
+
 // ---- desktop side -----------------------------------------------------------
 
 impl PluginHost {
@@ -951,4 +1004,43 @@ mod tests {
         assert!(valid_id("ai-completion"));
         assert!(!valid_id("../x") && !valid_id(".data") && !valid_id(""));
     }
+
+    fn execute(id: &str) -> PluginEvent {
+        PluginEvent::ExecuteCommand {
+            request_id: "1".into(),
+            id: id.into(),
+            arg: Some(r"\\host.example\share\pkg".into()),
+            chain: vec!["tools".into()],
+        }
+    }
+
+    #[test]
+    fn a_server_runs_only_plugin_commands_in_the_desktop_window() {
+        assert!(forwarded(&execute("plugin.tools.build")));
+        assert!(forwarded(&execute("plugin.acme.tools.build.all")));
+        for id in [
+            "plugins.installFromDisk",
+            "project.revokeTrust",
+            "project.removeTrustedLocation",
+            "ssh.startSession",
+            "file.openProjectPath",
+            "terminal.runCommand",
+            "plugin.",
+            "plugin.tools",
+            "plugin..build",
+            "plugin.tools.",
+        ] {
+            assert!(!forwarded(&execute(id)), "{id}");
+        }
+    }
+
+    #[test]
+    fn a_server_does_not_open_desktop_folders() {
+        let open = PluginEvent::OpenProject {
+            plugin_id: "tools".into(),
+            path: r"\\host.example\share\project".into(),
+            new_window: true,
+        };
+        assert!(!forwarded(&open));
+    }
 }

crates/ide-host/src/plugins/types.rs

@@ -218,6 +218,9 @@ pub enum PluginEvent {
     /// Reply to a content action in this window.
     #[serde(rename_all = "camelCase")]
     ContentTabReply { plugin_id: String, request_id: String, reply: ide_plugin::ContentTabReply },
+    /// Open two texts in this window's diff viewer.
+    #[serde(rename_all = "camelCase")]
+    OpenDiff { plugin_id: String, diff: ide_plugin::ContentDiff, file_name: Option<String> },
 
     /// Plugins, their status or their contributions changed: re-fetch `plugin_list`.
     CommandsChanged,

crates/ide-host/src/project.rs

@@ -8,7 +8,7 @@ use ide_language::{FileTypes, LanguageRegistry, SyntaxCache};
 use ide_lsp::LspManager;
 use ide_syntax::StructureService;
 use ide_text::{AppliedChange, ByteEdit};
-use ide_vcs::{Repo, Repos};
+use ide_vcs::{Backend, Repo, Repos};
 use ide_vfs::Watcher;
 use ide_workspace::documents::DocumentObserver;
 use ide_workspace::{DocumentInfo, Documents, FileMoves, LocalHistory, ProjectRoots, SettingsStore, SourceFolder};
@@ -541,7 +541,7 @@ impl Host {
         mark("git");
         tracing::info!("opened {} in window {window} in {} ms {laps:?}", root.display(), started.elapsed().as_millis());
 
-        let (db, http_history, agents) = self.project_services(&root, &project_key, &settings);
+        let (db, http_history, agents) = self.project_services(&root, &project_key, &settings, &sink);
         let db_sources_watch = db_sources_watch(&db, &sink, &self.runtime);
         let notebooks = crate::notebook::NotebookService::new(
             self.local_data_dir.join("notebook-runtime").join(uuid::Uuid::new_v4().to_string()),
@@ -634,6 +634,7 @@ impl Host {
         root: &Path,
         project_key: &str,
         settings: &Arc<SettingsStore>,
+        sink: &SharedSink,
     ) -> (Arc<ide_db::DbManager>, Arc<ide_http::History>, Arc<ide_agent::AgentManager>) {
         let db = Arc::new(
             ide_db::DbManager::new(
@@ -660,12 +661,23 @@ impl Host {
                 models_file: self.data_dir.join("agents").join("models.json"),
                 custom_agents_dir: Some(self.config_dir.join("agents")),
                 home_dir: dirs::home_dir(),
+                env_secrets: Some(Arc::new(AgentEnvSecrets {
+                    secrets: self.agent_secrets.clone(),
+                    sink: sink.clone(),
+                    told: AtomicBool::new(false),
+                })),
             },
             self.runtime.clone(),
         ));
         let settings = settings.clone();
+        {
+            let settings = settings.clone();
+            agents.set_new_task_approvals_hook(Arc::new(move || settings.effective().agents.new_task_approvals));
+        }
+        let approvals = self.mcp_approvals.clone();
+        let root = root.to_path_buf();
         agents.set_mcp_servers_hook(Box::new(move || {
-            ide_agent::mcp::servers_from_settings(&Default::default(), &settings.effective().agents.mcp_servers)
+            crate::ops::agent::session_mcp_servers(&settings, &approvals, &root)
         }));
         (db, http_history, agents)
     }
@@ -708,7 +720,7 @@ impl Host {
         documents.add_observer(Arc::new(HistoryObserver(history.clone())));
         let watcher = light_watcher(&dir, &sink, &documents, &history)?;
         let project_key = project_key(&dir);
-        let (db, http_history, agents) = self.project_services(&dir, &project_key, &settings);
+        let (db, http_history, agents) = self.project_services(&dir, &project_key, &settings, &sink);
         let notebooks = crate::notebook::NotebookService::new(
             self.local_data_dir.join("notebook-runtime").join(uuid::Uuid::new_v4().to_string()),
             sink.clone(),
@@ -959,6 +971,11 @@ impl Project {
         }
     }
 
+    /// `with_repo_of` through the backend-agnostic Changes-view surface.
+    pub fn with_backend_of<T>(&self, path: &Path, f: impl FnOnce(&dyn Backend) -> IdeResult<T>) -> IdeResult<T> {
+        self.with_repo_of(path, |r| f(r as &dyn Backend))
+    }
+
     fn run_in<T>(&self, repo: &Repo, f: impl FnOnce(&Repo) -> IdeResult<T>) -> IdeResult<T> {
         let settings = self.settings.effective();
         if self.is_trusted() {
@@ -968,6 +985,40 @@ impl Project {
         f(repo)
     }
 
+    /// `with_repo_at` through the backend-agnostic Changes-view surface.
+    pub fn with_backend_at<T>(&self, at: Option<&Path>, f: impl FnOnce(&dyn Backend) -> IdeResult<T>) -> IdeResult<T> {
+        self.with_repo_at(at, |r| f(r as &dyn Backend))
+    }
+
+    /// `with_log_repo_at` through the backend-agnostic Changes-view surface.
+    pub fn with_log_backend_at<T>(
+        &self,
+        at: Option<&Path>,
+        f: impl FnOnce(&dyn Backend) -> IdeResult<T>,
+    ) -> IdeResult<T> {
+        self.with_log_repo_at(at, |r| f(r as &dyn Backend))
+    }
+
+    /// `with_log_repo_of` through the backend-agnostic Changes-view surface.
+    pub fn with_log_backend_of<T>(&self, path: &Path, f: impl FnOnce(&dyn Backend) -> IdeResult<T>) -> IdeResult<T> {
+        self.with_log_repo_of(path, |r| f(r as &dyn Backend))
+    }
+
+    /// `with_repo` through the backend-agnostic Changes-view surface.
+    pub fn with_backend<T>(&self, f: impl FnOnce(&dyn Backend) -> IdeResult<T>) -> IdeResult<T> {
+        self.with_backend_at(None, f)
+    }
+
+    /// `with_repo_recorded` through the backend-agnostic Changes-view surface.
+    pub fn with_backend_recorded<T>(
+        &self,
+        at: Option<&Path>,
+        operation: Option<&str>,
+        f: impl FnOnce(&dyn Backend) -> IdeResult<T>,
+    ) -> IdeResult<T> {
+        self.with_repo_recorded(at, operation, |r| f(r as &dyn Backend))
+    }
+
     /// Runs `f` with the project's primary git repository, or fails when the project is not under git.
     pub fn with_repo<T>(&self, f: impl FnOnce(&Repo) -> IdeResult<T>) -> IdeResult<T> {
         self.with_repo_at(None, f)
@@ -992,7 +1043,7 @@ impl Project {
     ) -> IdeResult<T> {
         let Some(name) = operation else { return self.with_disk_sync(|| self.with_repo_at(at, f)) };
         self.history_label(&format!("Before {name}"));
-        if let Ok(changed) = self.with_repo_at(at, |r| r.status()) {
+        if let Ok(changed) = self.with_backend_at(at, |r| r.status()) {
             for file in changed.iter().take(HISTORY_BATCH_LIMIT) {
                 if let Err(e) = self.history.record_file(&file.path, &format!("Before {name}"), false) {
                     tracing::debug!("local history: {e}");
@@ -1586,6 +1637,37 @@ pub(crate) fn project_key(root: &Path) -> String {
     format!("{h:016x}")
 }
 
+/// The environment values of agent files in [`crate::agent_secrets::AgentSecrets`]; the
+/// window is told (once) when they had to go to the owner-only file instead.
+struct AgentEnvSecrets {
+    secrets: Arc<crate::agent_secrets::AgentSecrets>,
+    sink: SharedSink,
+    told: AtomicBool,
+}
+
+impl ide_agent::EnvSecrets for AgentEnvSecrets {
+    fn get(&self, key: &str) -> Option<String> {
+        self.secrets.get(key)
+    }
+
+    fn set(&self, key: &str, value: &str) -> IdeResult<()> {
+        if self.secrets.set(key, value)? == crate::agent_secrets::Kept::LocalFile
+            && !self.told.swap(true, Ordering::Relaxed)
+        {
+            self.secrets.notify_kept_locally(&self.sink);
+        }
+        Ok(())
+    }
+
+    fn delete(&self, key: &str) {
+        self.secrets.delete(key);
+    }
+
+    fn keys(&self, prefix: &str) -> Vec<String> {
+        self.secrets.keys(prefix)
+    }
+}
+
 struct LspObserver(Arc<LspManager>);
 
 impl DocumentObserver for LspObserver {

crates/ide-host/src/rpc.rs

@@ -185,15 +185,15 @@ impl Dispatcher {
         .add("fs_entry_kind", |c| async move { ops::fs::entry_kind(&c.host, c.arg("path")?).await })
         .add("fs_create_file", |c| async move { ops::fs::create_file(&c.host, &c.window, c.arg("path")?) })
         .add("fs_create_file_bytes", |c| async move {
-            ops::fs::create_file_bytes(&c.host, c.arg("path")?, c.arg("data")?).await
+            ops::fs::create_file_bytes(&c.host, &c.window, c.arg("path")?, c.arg("data")?).await
         })
         .add("fs_create_dir", |c| async move { ide_vfs::create_dir(&c.arg::<PathBuf>("path")?) })
-        .add("fs_rename", |c| async move { ops::fs::rename(&c.host, c.arg("from")?, c.arg("to")?).await })
+        .add("fs_rename", |c| async move { ops::fs::rename(&c.host, &c.window, c.arg("from")?, c.arg("to")?).await })
         .add("fs_set_writable", |c| async move {
             ops::fs::set_writable(&c.host, &c.window, c.arg("path")?, c.arg("writable")?)
         })
         .add("fs_delete", |c| async move { ops::fs::delete(&c.host, &c.window, c.arg("path")?).await })
-        .add("fs_copy", |c| async move { ops::fs::copy(&c.host, c.arg("from")?, c.arg("to")?).await })
+        .add("fs_copy", |c| async move { ops::fs::copy(&c.host, &c.window, c.arg("from")?, c.arg("to")?).await })
         .add("fs_copy_merge", |c| async move {
             ops::fs::copy_merge(
                 &c.host,
@@ -298,6 +298,56 @@ pub fn event_sink(peer: Arc<OnceLock<Peer>>, window: Option<String>) -> ide_core
     Arc::new(PeerSink { peer, window })
 }
 
+/// Whether a desktop shows an `event` notification of its server in the window. A server reports
+/// on its project; what this machine answers or owns itself (MCP approvals, app updates, window
+/// groups) never comes from it.
+pub fn client_accepts(event: &IdeEvent) -> bool {
+    match event {
+        IdeEvent::McpRequest { .. }
+        | IdeEvent::McpRequestClosed { .. }
+        | IdeEvent::WindowGroupsChanged
+        | IdeEvent::WindowFullscreenChanged
+        | IdeEvent::UpdateStatusChanged { .. }
+        | IdeEvent::UpdateAvailable { .. } => false,
+        IdeEvent::DbSourcesChanged
+        | IdeEvent::ProjectTrustChanged { .. }
+        | IdeEvent::FsChanged { .. }
+        | IdeEvent::ExcludedDirsChanged { .. }
+        | IdeEvent::DocPatched { .. }
+        | IdeEvent::DocDirty { .. }
+        | IdeEvent::WorkspaceEditApplied { .. }
+        | IdeEvent::DocLanguage { .. }
+        | IdeEvent::Diagnostics { .. }
+        | IdeEvent::Task { .. }
+        | IdeEvent::IndexState { .. }
+        | IdeEvent::VcsChanged { .. }
+        | IdeEvent::LanguageServer { .. }
+        | IdeEvent::LanguageServerWarning { .. }
+        | IdeEvent::LanguageServerRemoved { .. }
+        | IdeEvent::LspRefresh { .. }
+        | IdeEvent::TerminalExited { .. }
+        | IdeEvent::RunExited { .. }
+        | IdeEvent::Debug { .. }
+        | IdeEvent::Notify { .. }
+        | IdeEvent::SettingsChanged { .. }
+        | IdeEvent::ProjectRootsChanged { .. }
+        | IdeEvent::Askpass { .. }
+        | IdeEvent::AskpassDone { .. }
+        | IdeEvent::NotebookKernel { .. } => true,
+    }
+}
+
+/// The commands a desktop routes to its server: what `openidea-server` of this build answers,
+/// fixed here rather than taken from the server, so a server cannot move a command to this machine.
+pub fn client_commands() -> Vec<&'static str> {
+    let mut out = Dispatcher::standard().commands();
+    out.extend(crate::plugins::remote_host::COMMANDS);
+    out.push(crate::plugins::remote::SYNC_COMMAND);
+    out.sort_unstable();
+    out.dedup();
+    out
+}
+
 struct PeerSink {
     peer: Arc<OnceLock<Peer>>,
     window: Option<String>,
@@ -364,3 +414,56 @@ pub fn error_from_reply(e: ide_jsonrpc::RpcError) -> IdeError {
         other => other.into(),
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use ide_core::event::{AskpassKind, McpUiRequest, NotifyLevel};
+
+    #[test]
+    fn a_server_cannot_raise_desktop_prompts() {
+        let confirm = McpUiRequest::Confirm {
+            client: "agent".into(),
+            tool: "run".into(),
+            subject: "rm -rf".into(),
+            project: "/srv/app".into(),
+            detail: None,
+        };
+        let update = ide_core::updates::UpdateInfo {
+            version: "9.9.9".into(),
+            current_version: "0.1.0".into(),
+            notes: None,
+            date: None,
+        };
+        for event in [
+            IdeEvent::McpRequest { id: 1, request: confirm },
+            IdeEvent::McpRequestClosed { id: 1 },
+            IdeEvent::UpdateAvailable { update },
+            IdeEvent::UpdateStatusChanged {
+                status: ide_core::updates::UpdateStatus { last_checked: None, checking: true },
+            },
+            IdeEvent::WindowGroupsChanged,
+            IdeEvent::WindowFullscreenChanged,
+        ] {
+            assert!(!client_accepts(&event), "{event:?}");
+        }
+    }
+
+    #[test]
+    fn a_server_reports_its_project_to_the_desktop() {
+        for event in [
+            IdeEvent::FsChanged {
+                created: vec!["/srv/app/a".into()],
+                modified: vec![],
+                removed: vec![],
+                ignore_rules: vec![],
+            },
+            IdeEvent::VcsChanged { root: "/srv/app".into() },
+            IdeEvent::Notify { level: NotifyLevel::Info, title: "Build".into(), body: None },
+            IdeEvent::Askpass { id: 1, prompt: "Password".into(), kind: AskpassKind::Secret, remember: false },
+            IdeEvent::ProjectTrustChanged { root: "/srv/app".into(), trusted: true },
+        ] {
+            assert!(client_accepts(&event), "{event:?}");
+        }
+    }
+}

crates/ide-host/src/trust.rs

@@ -18,6 +18,15 @@ pub struct TrustStore {
     state: Mutex<IdeResult<TrustDecisions>>,
     /// Folders trusted for this process only, by the client that started it ([`TRUSTED_ROOT_ENV`]).
     inherited: Mutex<Vec<PathBuf>>,
+    remote_file: PathBuf,
+    remote: Mutex<IdeResult<RemoteDecisions>>,
+}
+
+/// This machine's decisions about remote projects, by location (see [`TrustStore::remote_decision`]).
+#[derive(Clone, Default, Serialize, Deserialize)]
+struct RemoteDecisions {
+    trusted: Vec<String>,
+    restricted: Vec<String>,
 }
 
 /// Set by the desktop when it starts the server in a dev container of a folder the user trusts
@@ -40,7 +49,37 @@ impl TrustStore {
             }
             Err(e) => Err(e.into()),
         };
-        Self { file, state: Mutex::new(state), inherited: Mutex::default() }
+        let remote_file = data.join("remote-project-trust.json");
+        let remote = match std::fs::read(&remote_file) {
+            Ok(bytes) => serde_json::from_slice(&bytes).map_err(|e| IdeError::invalid(e.to_string())),
+            Err(e) if e.kind() == std::io::ErrorKind::NotFound => Ok(RemoteDecisions::default()),
+            Err(e) => Err(e.into()),
+        };
+        Self { file, state: Mutex::new(state), inherited: Mutex::default(), remote_file, remote: Mutex::new(remote) }
+    }
+
+    /// The decision made on this machine for the remote project at `location` (`None`: none yet).
+    /// Commands a remote window runs here follow it, not the server's own trust.
+    pub fn remote_decision(&self, location: &str) -> IdeResult<Option<bool>> {
+        let remote = self.remote.lock().clone()?;
+        Ok(if remote.restricted.iter().any(|l| l == location) {
+            Some(false)
+        } else if remote.trusted.iter().any(|l| l == location) {
+            Some(true)
+        } else {
+            None
+        })
+    }
+
+    pub fn decide_remote(&self, location: &str, trusted: bool) -> IdeResult<()> {
+        let mut state = self.remote.lock();
+        let mut next = state.clone()?;
+        next.trusted.retain(|l| l != location);
+        next.restricted.retain(|l| l != location);
+        if trusted { &mut next.trusted } else { &mut next.restricted }.push(location.to_owned());
+        persist(&self.remote_file, &next)?;
+        *state = Ok(next);
+        Ok(())
     }
 
     pub fn decisions(&self) -> IdeResult<TrustDecisions> {
@@ -133,7 +172,7 @@ impl TrustStore {
     }
 }
 
-fn persist(file: &Path, state: &TrustDecisions) -> IdeResult<()> {
+fn persist<T: Serialize>(file: &Path, state: &T) -> IdeResult<()> {
     if let Some(parent) = file.parent() {
         std::fs::create_dir_all(parent)?;
     }
@@ -142,6 +181,61 @@ fn persist(file: &Path, state: &TrustDecisions) -> IdeResult<()> {
     Ok(())
 }
 
+type McpServers = std::collections::BTreeMap<String, ide_core::settings::AgentMcpServer>;
+
+/// Workspace MCP servers (a project's `agents.mcpServers`) the user turned on in Settings, by a
+/// fingerprint of the project and the server's definition. Agents start a workspace server only
+/// while its definition is one the user turned on, so a server added or changed in the project's
+/// file stays off until then.
+pub struct McpServerApprovals {
+    file: PathBuf,
+    approved: Mutex<std::collections::BTreeSet<String>>,
+}
+
+impl McpServerApprovals {
+    pub fn load(data: &Path) -> Self {
+        let file = data.join("mcp-server-approvals.json");
+        let approved = std::fs::read(&file).ok().and_then(|b| serde_json::from_slice(&b).ok()).unwrap_or_default();
+        Self { file, approved: Mutex::new(approved) }
+    }
+
+    fn fingerprint(root: &Path, name: &str, server: &ide_core::settings::AgentMcpServer) -> String {
+        // Turning a server off and on again doesn't change what it runs.
+        let server = ide_core::settings::AgentMcpServer { enabled: true, ..server.clone() };
+        let bytes = serde_json::to_vec(&(root, name, server)).expect("MCP server serializes");
+        blake3::hash(&bytes).to_hex().to_string()
+    }
+
+    pub fn approved(&self, root: &Path, name: &str, server: &ide_core::settings::AgentMcpServer) -> bool {
+        self.approved.lock().contains(&Self::fingerprint(root, name, server))
+    }
+
+    pub fn approve(&self, root: &Path, name: &str, server: &ide_core::settings::AgentMcpServer) -> IdeResult<()> {
+        let fingerprint = Self::fingerprint(root, name, server);
+        let mut approved = self.approved.lock();
+        if approved.contains(&fingerprint) {
+            return Ok(());
+        }
+        let mut next = approved.clone();
+        next.insert(fingerprint);
+        if let Some(parent) = self.file.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+        let bytes = serde_json::to_vec_pretty(&next).map_err(|e| IdeError::internal(e.to_string()))?;
+        ide_vfs::write_atomic(&self.file, &bytes)?;
+        *approved = next;
+        Ok(())
+    }
+
+    /// `workspace` with the servers the user hasn't turned on switched off.
+    pub fn apply(&self, root: &Path, mut workspace: McpServers) -> McpServers {
+        for (name, server) in &mut workspace {
+            server.enabled &= self.approved(root, name, server);
+        }
+        workspace
+    }
+}
+
 impl crate::Host {
     pub async fn set_project_trust(&self, path: &Path, trusted: bool, folder: bool) -> IdeResult<()> {
         self.trust.decide(path, trusted, folder)?;
@@ -317,6 +411,8 @@ pub fn restricted_command_allowed(cmd: &str) -> bool {
             | "remote_current"
             | "remote_disconnect"
             | "remote_connect"
+            | "remote_trust_status"
+            | "remote_trust_set"
             | "remote_bootstrap_list"
             | "wsl_distros"
             | "wsl_resolve"
@@ -471,4 +567,18 @@ mod tests {
     fn restricted_mode_allows_clipboard_write_text() {
         assert!(super::restricted_command_allowed("clipboard_write_text"));
     }
+
+    #[test]
+    fn remote_project_decisions_are_kept_on_this_machine() {
+        let tmp = tempfile::tempdir().unwrap();
+        let load = || super::TrustStore::load(&tmp.path().join("config"), &tmp.path().join("data"));
+        let store = load();
+        let here = r#"[{"kind":"ssh","config":"box"},"/srv/app"]"#;
+        assert_eq!(store.remote_decision(here).unwrap(), None);
+        store.decide_remote(here, true).unwrap();
+        assert_eq!(store.remote_decision(here).unwrap(), Some(true));
+        assert_eq!(store.remote_decision(r#"[{"kind":"ssh","config":"box"},"/srv/other"]"#).unwrap(), None);
+        store.decide_remote(here, false).unwrap();
+        assert_eq!(load().remote_decision(here).unwrap(), Some(false));
+    }
 }

crates/ide-host/tests/agent_approvals.rs

@@ -0,0 +1,57 @@
+//! The mode new agent tasks start in.
+
+use ide_core::NullSink;
+use ide_host::{Host, HostConfig};
+use serde_json::json;
+use std::path::Path;
+use std::sync::Arc;
+
+/// Codex's modes as it reported them last time, in "ask".
+fn remember_codex_modes(data: &Path) {
+    std::fs::create_dir_all(data.join("agents")).unwrap();
+    let modes = json!({ "codex": { "config": [ {
+        "id": "mode", "name": "Mode", "description": null, "category": "mode", "current": "ask",
+        "values": [ { "value": "read-only", "name": "Read Only", "description": null },
+                    { "value": "ask", "name": "Ask", "description": null },
+                    { "value": "full-access", "name": "Full Access", "description": null } ],
+        "via": "option" } ] } });
+    std::fs::write(data.join("agents/models.json"), modes.to_string()).unwrap();
+}
+
+fn codex_mode(host: &Host) -> Option<String> {
+    let providers = ide_host::ops::agent::providers(host, "main").unwrap();
+    let codex = providers.into_iter().find(|p| p.id == "codex").expect("codex is listed");
+    codex.config.into_iter().find(|o| o.id == "mode").and_then(|o| o.current)
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn new_tasks_start_asking_for_approval_when_the_user_chose_so() {
+    let tmp = tempfile::tempdir().unwrap();
+    let root = dunce::canonicalize(tmp.path()).unwrap().join("project");
+    std::fs::create_dir_all(root.join(".openidea")).unwrap();
+    let (config, data) = (tmp.path().join("config"), tmp.path().join("data"));
+    remember_codex_modes(&data);
+    std::fs::create_dir_all(&config).unwrap();
+    std::fs::write(config.join("settings.toml"), "[agents]\nnewTaskApprovals = \"ask\"\n").unwrap();
+    // A project's own settings don't choose this.
+    std::fs::write(root.join(".openidea/settings.toml"), "[agents]\nnewTaskApprovals = \"bypass\"\n").unwrap();
+    let host = Arc::new(Host::new(HostConfig {
+        config_dir: config.clone(),
+        data_dir: data,
+        local_data_dir: tmp.path().join("local"),
+        languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+        syntax: Arc::default(),
+        sink_for: Box::new(|_| Arc::new(NullSink)),
+        owner: |w| w,
+        runtime: tokio::runtime::Handle::current(),
+        project_environment: false,
+    }));
+    host.trust.decide(&root, true, false).unwrap();
+    host.open_project("main", &root).unwrap();
+    assert_eq!(codex_mode(&host).as_deref(), Some("ask"));
+
+    // The default keeps starting new tasks without approvals.
+    std::fs::remove_file(config.join("settings.toml")).unwrap();
+    host.project("main").unwrap().settings.reload();
+    assert_eq!(codex_mode(&host).as_deref(), Some("full-access"));
+}

crates/ide-host/tests/agent_env_secrets.rs

@@ -0,0 +1,86 @@
+//! Values of agents' environment variables live in the credential store; agent files keep only their names.
+
+use ide_core::NullSink;
+use ide_host::{Host, HostConfig};
+use ide_ssh::secrets::testing::{files_containing, use_memory_store};
+use std::collections::BTreeMap;
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+
+const VALUE: &str = "agent-env-value-5b2d81";
+
+fn host(dir: &Path) -> Arc<Host> {
+    Arc::new(Host::new(HostConfig {
+        config_dir: dir.join("config"),
+        data_dir: dir.join("data"),
+        local_data_dir: dir.join("data"),
+        languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+        syntax: Arc::default(),
+        sink_for: Box::new(|_| Arc::new(NullSink)),
+        owner: |w| w,
+        runtime: tokio::runtime::Handle::current(),
+        project_environment: false,
+    }))
+}
+
+fn open(host: &Host, tmp: &tempfile::TempDir) {
+    let root = dunce::canonicalize(tmp.path()).unwrap().join("project");
+    std::fs::create_dir_all(&root).unwrap();
+    host.trust.decide(&root, true, false).unwrap();
+    host.open_project("main", &root).unwrap();
+}
+
+fn env_of(host: &Host, id: &str) -> BTreeMap<String, String> {
+    let providers = ide_host::ops::agent::providers(host, "main").unwrap();
+    providers.into_iter().find(|p| p.id == id).unwrap_or_else(|| panic!("{id}")).env
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn agent_environment_values_stay_out_of_agent_files() {
+    use_memory_store();
+    let tmp = tempfile::tempdir().unwrap();
+    let host = host(tmp.path());
+    open(&host, &tmp);
+    let env = BTreeMap::from([("ANTHROPIC_API_KEY".to_owned(), VALUE.to_owned())]);
+    ide_host::ops::agent::set_env(&host, "main", "claude".into(), env.clone()).unwrap();
+    ide_host::ops::agent::save_custom_agent(
+        &host,
+        "main",
+        ide_agent::CustomAgentInput {
+            id: "mine".into(),
+            name: "Mine".into(),
+            command: "/opt/mine".into(),
+            args: vec![],
+            env: env.clone(),
+        },
+    )
+    .unwrap();
+    host.close_project("main");
+    assert_eq!(files_containing(tmp.path(), VALUE), Vec::<PathBuf>::new());
+
+    let host = self::host(tmp.path());
+    open(&host, &tmp);
+    assert_eq!(env_of(&host, "claude"), env);
+    assert_eq!(env_of(&host, "mine"), env);
+    ide_host::ops::agent::remove_custom_agent(&host, "main", "mine".into()).unwrap();
+    ide_host::ops::agent::set_env(&host, "main", "claude".into(), BTreeMap::new()).unwrap();
+    assert_eq!(host.agent_secrets.keys("agent/"), Vec::<String>::new());
+    host.close_project("main");
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn values_in_agent_files_move_to_the_credential_store() {
+    use_memory_store();
+    let tmp = tempfile::tempdir().unwrap();
+    std::fs::create_dir_all(tmp.path().join("config/agents")).unwrap();
+    std::fs::write(
+        tmp.path().join("config/agents/mine.toml"),
+        format!("command = \"/opt/mine\"\n[env]\nTOKEN = \"{VALUE}\"\n"),
+    )
+    .unwrap();
+    let host = host(tmp.path());
+    open(&host, &tmp);
+    assert_eq!(files_containing(tmp.path(), VALUE), Vec::<PathBuf>::new());
+    assert_eq!(env_of(&host, "mine"), BTreeMap::from([("TOKEN".to_owned(), VALUE.to_owned())]));
+    host.close_project("main");
+}

crates/ide-host/tests/agent_mcp.rs

@@ -0,0 +1,77 @@
+//! External MCP servers in Settings › Agents, as the host stores and lists them.
+
+use ide_agent::{McpScope, McpServer, McpServerInput};
+use ide_core::NullSink;
+use ide_core::settings::McpTransport;
+use ide_host::ops::agent::{mcp_import, mcp_list, mcp_save, mcp_set_enabled};
+use ide_host::{Host, HostConfig};
+use std::path::{Path, PathBuf};
+use std::sync::Arc;
+
+fn open(base: &Path) -> (Arc<Host>, PathBuf) {
+    let root = dunce::canonicalize(base).unwrap().join("project");
+    std::fs::create_dir_all(root.join(".openidea")).unwrap();
+    let host = Arc::new(Host::new(HostConfig {
+        config_dir: base.join("config"),
+        data_dir: base.join("data"),
+        local_data_dir: base.join("data"),
+        languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+        syntax: Arc::default(),
+        sink_for: Box::new(|_| Arc::new(NullSink)),
+        owner: |w| w,
+        runtime: tokio::runtime::Handle::current(),
+        project_environment: false,
+    }));
+    host.trust.decide(&root, true, false).unwrap();
+    host.open_project("main", &root).unwrap();
+    (host, root)
+}
+
+fn enabled(list: &[McpServer], id: &str) -> bool {
+    list.iter().find(|s| s.id == id).unwrap_or_else(|| panic!("{id} not listed: {list:?}")).enabled
+}
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn workspace_servers_from_the_project_file_stay_off_until_the_user_turns_them_on() {
+    let tmp = tempfile::tempdir().unwrap();
+    let (host, root) = open(tmp.path());
+    let settings_file = root.join(".openidea/settings.toml");
+    std::fs::write(&settings_file, "[agents.mcpServers.helper]\ncommand = \"node\"\nargs = [\"helper.js\"]\n").unwrap();
+    host.project("main").unwrap().settings.reload();
+
+    assert!(!enabled(&mcp_list(&host, "main").unwrap(), "workspace::helper"));
+    assert!(enabled(&mcp_set_enabled(&host, "main", "workspace::helper".into(), true).unwrap(), "workspace::helper"));
+    assert!(enabled(&mcp_list(&host, "main").unwrap(), "workspace::helper"));
+
+    // A changed definition is off again until turned back on.
+    std::fs::write(&settings_file, "[agents.mcpServers.helper]\ncommand = \"node\"\nargs = [\"other.js\"]\n").unwrap();
+    host.project("main").unwrap().settings.reload();
+    assert!(!enabled(&mcp_list(&host, "main").unwrap(), "workspace::helper"));
+
+    // What the user adds in Settings is on.
+    let saved = mcp_save(
+        &host,
+        "main",
+        McpServerInput {
+            id: None,
+            name: "mine".into(),
+            scope: McpScope::Workspace,
+            transport: McpTransport::Stdio,
+            enabled: true,
+            command: Some("uvx".into()),
+            args: vec!["mcp-server-git".into()],
+            env: vec![],
+            url: None,
+            headers: vec![],
+            agents: vec![],
+        },
+    )
+    .unwrap();
+    assert!(enabled(&saved, "workspace::mine"));
+
+    // Imported servers come from the project's own files: off until turned on.
+    std::fs::write(root.join(".mcp.json"), r#"{"mcpServers":{"imported":{"command":"uvx","args":["x"]}}}"#).unwrap();
+    let imported = mcp_import(&host, "main").unwrap();
+    assert!(!enabled(&imported, "workspace::imported"));
+    assert!(enabled(&imported, "workspace::mine"));
+}

crates/ide-host/tests/mcp.rs

@@ -112,6 +112,16 @@ async fn reads_unsaved_text_and_searches_the_overlay_with_a_limit() {
     assert_eq!(found["more"], true);
     let all = h.json("search_text", json!({"q":"fresh","limit":20})).await;
     assert_eq!(all["items"][0]["filePath"], "src/a.txt");
+    // The matched line comes with the result (unsaved text included), and lines around it on request.
+    assert_eq!(all["items"][0]["lineText"], "fresh needle text");
+    assert!(all["items"][0].get("contextAfter").is_none());
+    let after = h.json("search_text", json!({"q":"fresh","context":"+1"})).await;
+    assert_eq!(after["items"][0]["contextAfter"], json!(["needle needle"]));
+    let before = h.json("search_regex", json!({"q":"needle needle","context":"-1"})).await;
+    assert_eq!(before["items"][0]["lineText"], "needle needle");
+    assert_eq!(before["items"][0]["contextBefore"], json!(["fresh needle text"]));
+    let bad = h.error("search_text", json!({"q":"fresh","context":"around"})).await;
+    assert!(bad.contains("context must be"), "{bad}");
     let all = h.json("search_text", json!({"q":"needle","limit":20})).await;
     assert!(all["items"].as_array().unwrap().iter().all(|v| !v["filePath"].as_str().unwrap().contains("ignored")));
     let files = h.json("search_file", json!({"q":"*.txt","paths":["src/**"]})).await;
@@ -453,3 +463,166 @@ async fn brave_mode_runs_tools_without_asking_only_from_the_global_settings() {
     assert!(!format!("{result:?}").contains("denied"), "{result:?}");
     assert!(!h.events.lock().unwrap().iter().any(|e| matches!(e, IdeEvent::McpRequest { .. })), "nothing asked");
 }
+
+#[tokio::test(flavor = "multi_thread")]
+async fn check_files_says_why_a_file_could_not_be_checked() {
+    let h = Harness::new();
+    let untrusted = h.json("check_files", json!({"filePaths": ["src/a.txt"]})).await;
+    assert_eq!(untrusted["files"][0]["status"], "untrusted", "{untrusted}");
+    h.trust().await;
+    let files = h.json("check_files", json!({"filePaths": ["src/a.txt", "src/gone.txt"], "timeout": 5000})).await;
+    assert_eq!(files["files"][0]["filePath"], "src/a.txt");
+    assert_eq!(files["files"][0]["status"], "noLanguageServer", "{files}");
+    assert_eq!(files["files"][0]["problems"], json!([]));
+    assert_eq!(files["files"][1]["status"], "failed", "{files}");
+    assert!(files["files"][1]["error"].is_string());
+    // No cap of the tool's own: a very long timeout is taken as given, without overflowing.
+    let long = h.json("check_files", json!({"filePaths": ["src/a.txt"], "timeout": 9_000_000_000_000_i64})).await;
+    assert_eq!(long["files"][0]["status"], "noLanguageServer", "{long}");
+    let none = h.error("check_files", json!({"filePaths": []})).await;
+    assert!(none.contains("at least one file"), "{none}");
+}
+
+/// Answers `run_command`'s window requests the way the Run tool window does: starts the
+/// agent tab's configuration (shell from the default) and says whether it started. Returns
+/// the configurations it started, for reruns.
+#[cfg(unix)]
+fn run_tool_window(h: &Harness) -> Arc<std::sync::Mutex<Vec<ide_run::RunConfig>>> {
+    let started = Arc::new(std::sync::Mutex::new(Vec::new()));
+    let (host, events, out) = (h.host.clone(), h.events.clone(), started.clone());
+    tokio::spawn(async move {
+        let mut handled = std::collections::HashSet::new();
+        loop {
+            let request = events.lock().unwrap().iter().find_map(|e| match e {
+                IdeEvent::McpRequest {
+                    id,
+                    request: ide_core::event::McpUiRequest::AgentRun { name, command, cwd, env },
+                } if !handled.contains(id) => Some((*id, name.clone(), command.clone(), cwd.clone(), env.clone())),
+                _ => None,
+            });
+            let Some((id, name, command, cwd, env)) = request else {
+                tokio::time::sleep(std::time::Duration::from_millis(10)).await;
+                continue;
+            };
+            handled.insert(id);
+            let mut config = ide_run::RunConfig {
+                id: format!("mcp-agent:{name}"),
+                name: name.clone(),
+                kind: "shell".into(),
+                command,
+                args: Vec::new(),
+                cwd: Some(cwd),
+                env,
+                detected: false,
+                is_test: false,
+                debug_adapter: None,
+                allow_parallel: true,
+                extras: Default::default(),
+            };
+            config.extras.params.insert(ide_host::mcp::AGENT_PARAM.into(), name);
+            config.extras.target = Some(String::new());
+            out.lock().unwrap().push(config.clone());
+            let result = ide_host::ops::run::start(&host, "main", config, Arc::new(|_| {})).await;
+            let error = result.err().map(|e| e.message);
+            let _ = host.mcp_requests.answer("main", id, error.is_none(), error);
+        }
+    });
+    started
+}
+
+#[cfg(unix)]
+fn agent_process(h: &Harness, name: &str) -> ide_core::RunId {
+    let id = format!("mcp-agent:{name}");
+    h.host.processes.list().into_iter().filter(|r| r.config_id == id && r.running).map(|r| r.id).max().unwrap()
+}
+
+#[cfg(unix)]
+#[tokio::test(flavor = "multi_thread")]
+async fn agent_commands_run_in_named_tabs_and_report_what_the_user_did() {
+    let h = Harness::new();
+    h.trust().await;
+    h.host.mcp_requests.set_ready("main", true);
+    h.host
+        .global_settings
+        .set(ide_workspace::SettingsScope::Global, "mcpServer.runWithoutConfirmation", json!(true))
+        .unwrap();
+    let started = run_tool_window(&h);
+
+    // A command that finishes within the wait, in a tab named with the prefix.
+    let done = h.json("run_command", json!({"name": "check", "command": "echo hel''lo; exit 3"})).await;
+    assert_eq!(done["name"], "_agent_check", "{done}");
+    assert_eq!(done["state"], "failed", "{done}");
+    assert_eq!(done["exitCode"], 3);
+    assert_eq!(done["startedBy"], "agent");
+    assert!(done["output"].as_str().unwrap().contains("hello"), "{done}");
+    assert!(done.get("interventions").is_none());
+
+    // The finished name runs the next command; a running one is refused, never stopped.
+    let running =
+        h.json("run_command", json!({"name": "_agent_check", "command": "echo ready; sleep 30", "timeout": 0})).await;
+    assert_eq!(running["state"], "running", "{running}");
+    let matched = h.json("wait_for_run", json!({"name": "check", "pattern": "(?m)^ready", "timeout": 10000})).await;
+    assert_eq!(matched["waitEnded"], "matched", "{matched}");
+    let refused = h.error("run_command", json!({"name": "check", "command": "true"})).await;
+    assert!(refused.contains("still running `echo ready; sleep 30`"), "{refused}");
+    assert!(refused.contains("Last output:\nready"), "the refusal quotes the last output: {refused}");
+
+    // What the user types (a line from the Run console's input) ends a wait at once, with advice for the agent.
+    let process = agent_process(&h, "_agent_check");
+    ide_host::ops::run::stdin(&h.host, process, "yes\n").unwrap();
+    let typed = h.json("wait_for_run", json!({"name": "check", "timeout": 10000})).await;
+    assert_eq!(typed["waitEnded"], "userIntervened", "{typed}");
+    assert_eq!(typed["interventions"][0]["message"], "User input: yes");
+    assert!(typed["advice"].as_str().unwrap().contains("Do not stop the process"));
+    let input = h.json("send_run_input", json!({"name": "check", "text": "abc", "keys": ["Enter"]})).await;
+    assert!(input.get("interventions").is_none(), "the agent's own input is no intervention: {input}");
+
+    let stopped = h.json("stop_run", json!({"name": "check", "force": true, "timeout": 10000})).await;
+    assert_eq!(stopped["state"], "stoppedByAgent", "{stopped}");
+    assert!(stopped.get("interventions").is_none());
+
+    // The user's Stop, rerun and closing the tab are reported with their time.
+    h.json("run_command", json!({"name": "server", "command": "sleep 30", "timeout": 0})).await;
+    ide_host::ops::run::stop(&h.host, "main", agent_process(&h, "_agent_server")).unwrap();
+    let stop = h.json("wait_for_run", json!({"name": "server", "timeout": 10000})).await;
+    assert!(stop["interventions"][0]["message"].as_str().unwrap().starts_with("The user stopped this command at"));
+    let ended = h.json("wait_for_run", json!({"name": "server", "timeout": 10000})).await;
+    assert_eq!(ended["state"], "stoppedByUser", "{ended}");
+
+    let config = started.lock().unwrap().last().cloned().unwrap();
+    ide_host::ops::run::start(&h.host, "main", config, Arc::new(|_| {})).await.unwrap();
+    let status = h.json("get_run_status", json!({"name": "server"})).await;
+    assert_eq!(status["startedBy"], "user", "{status}");
+    assert!(status["interventions"][0]["message"].as_str().unwrap().starts_with("The user reran this command at"));
+    h.json("stop_run", json!({"name": "server", "force": true, "timeout": 10000})).await;
+    h.host.mcp_agent_runs.closed(&h.root, "_agent_server");
+    let closed = h.json("get_run_status", json!({"name": "server"})).await;
+    assert!(closed["tabClosedAt"].is_string(), "{closed}");
+    assert!(closed["interventions"][0]["message"].as_str().unwrap().starts_with("The user closed this tab at"));
+
+    let log = h.json("read_run_output", json!({"name": "check", "maxLinesCount": 20})).await;
+    assert!(log["output"].as_str().unwrap().contains("ready"), "{log}");
+    let from_start = h.json("read_run_output", json!({"name": "check", "offset": 0})).await;
+    assert!(from_start["output"].as_str().unwrap().contains("hello"), "one log across the tab's commands");
+    let runs = h.json("list_runs", json!({})).await;
+    assert_eq!(runs["runs"].as_array().unwrap().len(), 2, "{runs}");
+    let missing = h.error("get_run_status", json!({"name": "nothing"})).await;
+    assert!(missing.contains("no agent tab named `_agent_nothing`"), "{missing}");
+
+    // Pipes: plain lines, cleaned of escapes and cut to maxLinesCount (the end stays by default).
+    let printf = "printf '\\033[31mone\\033[0m\\ntwo\\nthree\\n'";
+    let lines =
+        h.json("run_command", json!({"name": "lines", "command": printf, "maxLinesCount": 2, "timeout": 10000})).await;
+    assert_eq!(lines["output"], "<<<...content truncated...>>>\ntwo\nthree\n", "{lines}");
+    assert_eq!(lines["truncatedLines"], 1);
+    let head = h.json("read_run_output", json!({"name": "lines", "maxLinesCount": 1, "truncateMode": "END"})).await;
+    assert_eq!(head["output"], "one\n<<<...content truncated...>>>\n", "{head}");
+
+    // Ctrl+C stops the command as stop_run does; terminal keys have no meaning on pipes.
+    h.json("run_command", json!({"name": "interrupt", "command": "sleep 30", "timeout": 0})).await;
+    let key = h.error("send_run_input", json!({"name": "interrupt", "keys": ["Up"]})).await;
+    assert!(key.contains("runs on pipes"), "{key}");
+    h.json("send_run_input", json!({"name": "interrupt", "keys": ["Ctrl+C"]})).await;
+    let interrupted = h.json("wait_for_run", json!({"name": "interrupt", "timeout": 10000})).await;
+    assert_eq!(interrupted["state"], "stoppedByAgent", "{interrupted}");
+}

crates/ide-host/tests/plugins.rs

@@ -6352,6 +6352,26 @@ fn api14_stage3_configurations_test_results_and_content_actions_use_real_exports
     assert!(f.host.parse_test_results("main", "plugin:execution:dynamic", "trap".into()).unwrap().is_none());
 }
 
+#[cfg(unix)]
+#[test]
+fn a_plugin_command_opens_a_diff_in_its_window() {
+    let f = execution_fixture();
+    f.take_events();
+    f.run("execution", "diff", None).unwrap();
+    f.host.flush_events_at(Instant::now() + Duration::from_secs(3));
+    assert!(eventually(|| {
+        f.events.lock().iter().any(|(client, event)| {
+            client.as_deref() == Some("main")
+                && matches!(event, PluginEvent::OpenDiff { plugin_id, diff, file_name }
+                    if plugin_id == "execution"
+                        && diff.left == "before\n"
+                        && diff.right == "after\n"
+                        && diff.title.as_deref() == Some("Review")
+                        && file_name.as_deref() == Some("src/review.rs"))
+        })
+    }));
+}
+
 #[test]
 fn api14_fixture_exports_test_selection() {
     let f = fixture(Limits::default());
@@ -6682,7 +6702,11 @@ fn project_write_cannot_replace_the_git_file_of_a_linked_worktree() {
     }
     for rel in spellings {
         let err = f.run("misbehave", "projwrite", Some(rel)).unwrap_err();
-        assert!(err.contains("git's own files"), "{rel}: {err}");
+        // On Windows a stream name is refused before the path is looked at at all; elsewhere a colon
+        // is an ordinary character and the `.git` rule applies.
+        let refused =
+            if cfg!(windows) && rel.contains(':') { "file streams are not allowed" } else { "git's own files" };
+        assert!(err.contains(refused), "{rel}: {err}");
         assert_eq!(std::fs::read_to_string(&pointer).unwrap(), gitdir, "{rel}");
     }
 }

crates/ide-host/tests/rpc.rs

@@ -455,3 +455,29 @@ async fn properties_conversion_through_remote_dispatch_without_a_remote_host() {
     invoke(&peer, "close_project", json!({})).await.unwrap();
     peer.kill();
 }
+
+#[tokio::test(flavor = "multi_thread", worker_threads = 2)]
+async fn the_desktop_routes_exactly_what_a_server_of_this_build_answers() {
+    let tmp = tempfile::tempdir().unwrap();
+    let base = tmp.path().join("server");
+    let peer_slot = Arc::new(OnceLock::new());
+    let host = Arc::new(Host::new(HostConfig {
+        config_dir: base.join("config"),
+        data_dir: base.join("data"),
+        local_data_dir: base.join("data"),
+        languages: Arc::new(ide_language::LanguageRegistry::load(None).unwrap()),
+        syntax: Arc::default(),
+        sink_for: Box::new(|_| Arc::new(ide_core::NullSink)),
+        owner: |w| w,
+        runtime: tokio::runtime::Handle::current(),
+        project_environment: false,
+    }));
+    // As `openidea-server` assembles its commands.
+    let plugins = ide_host::plugins::remote_host::RemotePlugins::start(&base.join("data"), &host, peer_slot).unwrap();
+    let mut dispatcher = Dispatcher::standard();
+    plugins.register(&mut dispatcher);
+    dispatcher.add(ide_host::plugins::remote::SYNC_COMMAND, |_| async { Ok(()) });
+    assert_eq!(rpc::client_commands(), dispatcher.commands());
+    assert!(rpc::client_commands().contains(&"term_spawn"));
+    plugins.host().shutdown();
+}

crates/ide-host/tests/unity.rs

@@ -83,10 +83,10 @@ async fn opens_unity_without_generated_solutions_and_excludes_caches_from_the_in
     };
     let original_metadata = "fileFormatVersion: 2\nguid: 11111111111111111111111111111111\n";
     std::fs::write(meta(&original), original_metadata).unwrap();
-    ops::fs::rename(&host, original.clone(), renamed.clone()).await.unwrap();
+    ops::fs::rename(&host, "main", original.clone(), renamed.clone()).await.unwrap();
     assert!(!original.exists() && !meta(&original).exists());
     assert_eq!(std::fs::read_to_string(meta(&renamed)).unwrap(), original_metadata);
-    ops::fs::copy(&host, renamed.clone(), copied.clone()).await.unwrap();
+    ops::fs::copy(&host, "main", renamed.clone(), copied.clone()).await.unwrap();
     assert!(copied.exists());
     assert_ne!(std::fs::read_to_string(meta(&copied)).unwrap(), original_metadata);
     assert_eq!(std::fs::read_to_string(meta(&renamed)).unwrap(), original_metadata);

crates/ide-index/Cargo.toml

@@ -21,6 +21,9 @@ ignore.workspace = true
 globset.workspace = true
 postcard = { version = "1.1", default-features = false, features = ["use-std"] }
 
+[build-dependencies]
+blake3.workspace = true
+
 [dev-dependencies]
 tempfile.workspace = true
 criterion = { version = "0.5", default-features = false }

crates/ide-index/build.rs

@@ -0,0 +1,33 @@
+//! Hashes this crate's sources into `INDEX_SOURCE_HASH`: what is extracted and stored for a
+//! file (ignored state, size limit, record layout) is decided here as well as in
+//! `ide-language`, so the persistent index is rebuilt when either changes.
+
+use std::path::{Path, PathBuf};
+
+fn main() {
+    let src = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap()).join("src");
+    println!("cargo:rerun-if-changed={}", src.display());
+    let mut files = Vec::new();
+    collect(&src, &mut files);
+    files.sort();
+    let mut h = blake3::Hasher::new();
+    for file in files {
+        h.update(file.strip_prefix(&src).unwrap_or(&file).to_string_lossy().replace('\\', "/").as_bytes());
+        h.update(b"\0");
+        h.update(&std::fs::read(&file).unwrap());
+        h.update(b"\0");
+    }
+    println!("cargo:rustc-env=INDEX_SOURCE_HASH={}", &h.finalize().to_hex()[..16]);
+}
+
+fn collect(dir: &Path, out: &mut Vec<PathBuf>) {
+    let Ok(entries) = std::fs::read_dir(dir) else { return };
+    for entry in entries.flatten() {
+        let path = entry.path();
+        if path.is_dir() {
+            collect(&path, out);
+        } else {
+            out.push(path);
+        }
+    }
+}

crates/ide-index/src/store.rs

@@ -45,7 +45,7 @@ impl Store {
             }
         };
         let store = Self { db: RwLock::new(db) };
-        let stamp = format!("{SCHEMA}\n{fingerprint}\n{}", root.display());
+        let stamp = format!("{SCHEMA}\n{}\n{fingerprint}\n{}", env!("INDEX_SOURCE_HASH"), root.display());
         match store.meta("stamp") {
             Ok(Some(v)) if v == stamp.as_bytes() => {}
             _ => {

crates/ide-language/Cargo.toml

@@ -58,6 +58,9 @@ tree-sitter-graphql = "0.3.0"
 tree-sitter-prisma-io = "1.6.0"
 tree-sitter-gdscript = "6.1.0"
 
+[build-dependencies]
+blake3.workspace = true
+
 [dev-dependencies]
 criterion = { version = "0.5", default-features = false }
 tempfile.workspace = true

crates/ide-language/build.rs

@@ -0,0 +1,61 @@
+//! Hashes everything that decides what `Syntax::tags` extracts (this crate's
+//! sources, queries, language definitions and the locked tree-sitter crates)
+//! into `SYNTAX_SOURCE_HASH`, so persistent caches survive releases that leave
+//! extraction untouched.
+
+use std::path::{Path, PathBuf};
+
+fn main() {
+    let manifest = PathBuf::from(std::env::var("CARGO_MANIFEST_DIR").unwrap());
+    let workspace = manifest.join("../..");
+    let lock = workspace.join("Cargo.lock");
+    let inputs = [manifest.join("src"), manifest.join("queries"), workspace.join("languages")];
+
+    let mut h = blake3::Hasher::new();
+    for dir in &inputs {
+        println!("cargo:rerun-if-changed={}", dir.display());
+        let mut files = Vec::new();
+        collect(dir, &mut files);
+        files.sort();
+        for file in files {
+            let rel = file.strip_prefix(&workspace).unwrap_or(&file);
+            h.update(rel.to_string_lossy().replace('\\', "/").as_bytes());
+            h.update(b"\0");
+            h.update(&std::fs::read(&file).unwrap());
+            h.update(b"\0");
+        }
+    }
+    println!("cargo:rerun-if-changed={}", lock.display());
+    match std::fs::read_to_string(&lock) {
+        Ok(text) => h.update(tree_sitter_packages(&text).as_bytes()),
+        // Built outside the workspace: fall back to the crate version.
+        Err(_) => h.update(std::env::var("CARGO_PKG_VERSION").unwrap().as_bytes()),
+    };
+    println!("cargo:rustc-env=SYNTAX_SOURCE_HASH={}", &h.finalize().to_hex()[..16]);
+}
+
+fn collect(dir: &Path, out: &mut Vec<PathBuf>) {
+    let Ok(entries) = std::fs::read_dir(dir) else { return };
+    for entry in entries.flatten() {
+        let path = entry.path();
+        if path.is_dir() {
+            collect(&path, out);
+        } else {
+            out.push(path);
+        }
+    }
+}
+
+/// `name version checksum` of every locked `tree-sitter*` package.
+fn tree_sitter_packages(lock: &str) -> String {
+    let mut out = String::new();
+    for package in lock.split("[[package]]") {
+        let field = |key: &str| {
+            package.lines().find_map(|l| l.strip_prefix(key)?.strip_prefix(" = ")).unwrap_or("").trim_matches('"')
+        };
+        if field("name").starts_with("tree-sitter") {
+            out.push_str(&format!("{} {} {}\n", field("name"), field("version"), field("checksum")));
+        }
+    }
+    out
+}

crates/ide-language/src/syntax/mod.rs

@@ -132,29 +132,11 @@ impl Syntax {
         SPECS.iter().map(|s| s.name)
     }
 
-    /// Changes whenever extraction output may change (grammar set, queries,
-    /// crate version); persistent caches of [`Syntax::tags`] key on it.
+    /// Changes whenever extraction output may change (this crate's sources,
+    /// queries, language definitions, tree-sitter crate versions; see
+    /// `build.rs`); persistent caches of [`Syntax::tags`] key on it.
     pub fn fingerprint(&self) -> String {
-        static FP: OnceLock<String> = OnceLock::new();
-        FP.get_or_init(|| {
-            let mut h = blake3::Hasher::new();
-            h.update(env!("CARGO_PKG_VERSION").as_bytes());
-            // Bump when web definitions (`.class`, `#id`, `--var` tags) change.
-            h.update(b"web-definitions-1");
-            for s in SPECS {
-                h.update(s.name.as_bytes());
-                h.update(&Language::new(s.language).abi_version().to_le_bytes());
-                h.update(s.outline.as_bytes());
-                for list in [s.fold_nodes, s.fold_bodies, s.imports, s.constructors] {
-                    for k in list {
-                        h.update(k.as_bytes());
-                        h.update(b"\0");
-                    }
-                }
-            }
-            h.finalize().to_hex()[..16].to_owned()
-        })
-        .clone()
+        env!("SYNTAX_SOURCE_HASH").to_owned()
     }
 
     /// Whether a tree-sitter grammar is bundled for this language.

crates/ide-lsp/src/inspect.rs

@@ -22,6 +22,9 @@ use std::time::{Duration, Instant};
 /// How long Inspect Code waits for a server that is still starting (jdtls,
 /// rust-analyzer on a large workspace).
 const INSPECT_START_WAIT: Duration = Duration::from_secs(60);
+/// Quiet period after a publish before a checked file counts as done (follow-up publishes:
+/// syntax first, semantics later).
+const CHECK_SETTLE: Duration = Duration::from_millis(500);
 
 #[derive(Clone, Copy, Debug)]
 pub struct InspectOptions {
@@ -48,6 +51,29 @@ pub trait InspectHost: Send + Sync + 'static {
     fn close(&self, doc: DocId);
 }
 
+/// One language server's part in a [`DocumentCheck`].
+#[derive(Clone, Debug)]
+pub struct CheckedServer {
+    pub name: String,
+    /// Its state when the check ended: not `Ready`/`Busy` means it could not check.
+    pub status: ide_core::event::ServerStatus,
+    /// Why it isn't running (not installed, misconfigured, crashed), as the status bar says.
+    pub message: Option<String>,
+    /// Its diagnostics are in the result.
+    pub checked: bool,
+    /// It was still analysing (or had not published for this change) when the wait ended.
+    pub incomplete: bool,
+    /// Asking it failed.
+    pub error: Option<String>,
+}
+
+/// Fresh diagnostics of a document, with every language server that serves it.
+#[derive(Clone, Debug, Default)]
+pub struct DocumentCheck {
+    pub diagnostics: Vec<Diagnostic>,
+    pub servers: Vec<CheckedServer>,
+}
+
 /// What became of one file.
 #[derive(Clone, Debug)]
 pub enum FileInspection {
@@ -198,6 +224,96 @@ impl LspManager {
         }
     }
 
+    /// Fresh diagnostics of the open document `doc`, whose text the caller just synced
+    /// (`changed`: at that instant, so diagnostics published before it are stale). Tells the
+    /// servers the document was saved, since checks that run on save (rust-analyzer's
+    /// `cargo check`) don't run for a change made outside the IDE, then waits for each server
+    /// to be ready, to answer for this text and to finish the background work it started, up
+    /// to `timeout`. Every server serving the document is reported, so a caller can tell "no
+    /// problems" from "nothing could check".
+    pub async fn check_document(
+        &self,
+        doc: DocId,
+        changed: Option<Instant>,
+        timeout: Duration,
+        cancel: &CancellationToken,
+    ) -> IdeResult<DocumentCheck> {
+        let snap = self.snapshot(doc)?;
+        let deadline = tokio::time::Instant::now() + timeout;
+        let left = || deadline.saturating_duration_since(tokio::time::Instant::now());
+        let ready = tokio::select! {
+            r = futures::future::join_all(snap.servers.iter().map(|s| s.wait_ready(left()))) => r,
+            () = cancel.cancelled() => return Err(IdeError::cancelled()),
+        };
+        // Once the servers have the document: a save sent while one starts would not reach it.
+        self.did_save(doc, snap.text.as_str());
+        let per_server = snap.servers.iter().zip(ready).map(|(server, run)| async {
+            let mut report = CheckedServer {
+                name: server.name.clone(),
+                status: server.status(),
+                message: server.status_message(),
+                checked: false,
+                incomplete: false,
+                error: None,
+            };
+            let Some(run) = run else { return Some((report, Vec::new())) };
+            let t = Target { server: server.clone(), run };
+            if !t.caps().restriction.diagnostics() {
+                return None;
+            }
+            let pull = t.caps().has("diagnosticProvider");
+            let mut since = changed;
+            let raw = loop {
+                // A pull asks for this text; a push server is waited on to publish for it.
+                let raw = if pull {
+                    server.wait_idle(left(), cancel).await;
+                    self.pull_diagnostics(&t, &snap.uri, cancel, left()).await
+                } else {
+                    let opts = InspectOptions { concurrency: 1, timeout: left(), settle: CHECK_SETTLE };
+                    wait_for_publish(server, &snap.path, since, opts, cancel).await
+                };
+                // The save may have started work (a `cargo check`) that publishes when it ends.
+                if raw.is_err() || pull || !server.is_busy() || left().is_zero() {
+                    break raw;
+                }
+                if !server.wait_idle(left(), cancel).await {
+                    break raw.map(|_| server.diagnostics_for(&snap.path));
+                }
+                // Idle: its last publish is final once quiet.
+                since = None;
+            };
+            report.status = server.status();
+            match raw {
+                Ok(items) => {
+                    report.checked = true;
+                    let fresh =
+                        pull || changed.is_none_or(|c| server.last_published(&snap.path).is_some_and(|p| p >= c));
+                    report.incomplete = !fresh || server.is_busy();
+                    let conv = self.conv(t.enc());
+                    let items = items
+                        .into_iter()
+                        .map(|d| convert::diagnostic(&conv, &snap.path, d, &t.server.name))
+                        .collect::<Vec<_>>();
+                    Some((report, items))
+                }
+                Err(e) => {
+                    report.error = Some(e.message);
+                    Some((report, Vec::new()))
+                }
+            }
+        });
+        let results = tokio::select! {
+            r = futures::future::join_all(per_server) => r,
+            () = cancel.cancelled() => return Err(IdeError::cancelled()),
+        };
+        let mut out = DocumentCheck::default();
+        for (report, items) in results.into_iter().flatten() {
+            out.servers.push(report);
+            out.diagnostics.extend(items);
+        }
+        Ok(out)
+    }
+
     async fn pull_diagnostics(
         &self,
         t: &Target,

crates/ide-lsp/src/lib.rs

@@ -40,7 +40,7 @@ mod vue_navigation;
 mod vue_refs;
 
 pub use injections::{InjectedRange, InjectionProvider, MAX_INJECTED_DOCUMENT_BYTES};
-pub use inspect::{FileInspection, InspectHost, InspectOptions};
+pub use inspect::{CheckedServer, DocumentCheck, FileInspection, InspectHost, InspectOptions};
 pub use jdtls::jvm_inspect::JdtJvmInspector;
 pub use kotlin_lsp::{KotlinDebugServer, KotlinDebugUnavailable};
 pub use launch::{LaunchError, Launcher, ProcessLauncher};
@@ -378,15 +378,32 @@ fn read_jar_source(uri: &str, encoding: Option<&str>) -> Option<(String, ide_vfs
 /// Library classes in `jar:` targets (the official Kotlin LSP) go to their source
 /// in the artifact's sources jar when it is cached, at the declaration of the
 /// name navigated from; [`LspManager::virtual_document`] serves it.
-async fn library_sources(snap: &DocSnap, pos: Pos, locs: Vec<Location>) -> Vec<Location> {
-    if !locs.iter().any(|l| l.uri.as_deref().is_some_and(|u| u.starts_with("jar:") && u.ends_with(".class"))) {
+async fn library_sources(snap: &DocSnap, root: &Path, pos: Pos, locs: Vec<Location>) -> Vec<Location> {
+    let jar_class = |u: &str| u.starts_with("jar:") && u.ends_with(".class");
+    // The path names the class's source file (`Db.kt`); the handle in the query, the class.
+    let jdt_class = |u: &str| u.starts_with("jdt://contents/") && u.contains(".class");
+    if !locs.iter().any(|l| l.uri.as_deref().is_some_and(|u| jar_class(u) || jdt_class(u))) {
         return locs;
     }
     let name = library_source::identifier_at(snap.text.line(pos.line as usize), pos.col).map(str::to_owned);
+    let root = root.to_owned();
     tokio::task::spawn_blocking(move || {
         locs.into_iter()
             .map(|loc| {
-                let Some(uri) = loc.uri.as_deref().filter(|u| u.starts_with("jar:") && u.ends_with(".class")) else {
+                // A class JDT finds in a project's class folder (Kotlin compiled for Java code):
+                // the project's source file, not the decompiled class.
+                if let Some(uri) = loc.uri.as_deref().filter(|u| jdt_class(u)) {
+                    let source = library_source::folder_class(uri)
+                        .and_then(|(package, class)| library_source::project_class_source(&root, &package, &class));
+                    let Some(source) = source else { return loc };
+                    let range = name
+                        .as_deref()
+                        .zip(std::fs::read_to_string(&source).ok())
+                        .map(|(n, text)| library_source::declaration_range(&text, n))
+                        .unwrap_or_default();
+                    return Location { path: source.into(), range, uri: None };
+                }
+                let Some(uri) = loc.uri.as_deref().filter(|u| jar_class(u)) else {
                     return loc;
                 };
                 let Some((source, loaded)) = library_source::class_source(uri, None) else { return loc };
@@ -1683,7 +1700,7 @@ impl LspManager {
             Ok(found) => {
                 let locs =
                     convert::goto_response(&self.conv(t.enc()), lsp::GotoDefinitionResponse::Array(found.locations));
-                let locs = library_sources(snap, pos, locs).await;
+                let locs = library_sources(snap, &self.project_root, pos, locs).await;
                 self.note_virtual(&t.server, locs.iter().map(|l| l.uri.as_deref()));
                 (locs, found.complete)
             }
@@ -1732,7 +1749,7 @@ impl LspManager {
             match r {
                 Ok(Some(r)) => {
                     let locs = convert::goto_response(&self.conv(t.enc()), r);
-                    let locs = library_sources(snap, pos, locs).await;
+                    let locs = library_sources(snap, &self.project_root, pos, locs).await;
                     self.note_virtual(&t.server, locs.iter().map(|l| l.uri.as_deref()));
                     self.note_arduino_sources(&t.server, &locs);
                     let locs = merge_locations(first, locs);

crates/ide-lsp/src/library_source.rs

@@ -226,6 +226,66 @@ pub(crate) fn identifier_at(line: &str, col: u32) -> Option<&str> {
     (!word.is_empty() && !word.starts_with(|c: char| c.is_ascii_digit())).then_some(word)
 }
 
+/// A class of a class folder on JDT's classpath, as `(package path, class name)`, read
+/// from the element handle in the query:
+/// `jdt://contents/<folder>/<pkg>/<File>?=<project>/<escaped folder>[=/<attribute>=/<value>]…<pkg(Name.class`
+/// (`<File>` is the class's SourceFile, `Db.kt` for a Kotlin class). A folder is a project's
+/// own build output (the Kotlin classes the IDE compiles for JDT among them), never a
+/// dependency, which is a jar or a JDK module.
+pub(crate) fn folder_class(uri: &str) -> Option<(String, String)> {
+    uri.strip_prefix("jdt://contents/")?;
+    let query = percent_decode_str(uri.split_once('?')?.1).decode_utf8().ok()?;
+    let (root, element) = query.split_once('/')?.1.split_once('<')?;
+    let folder = PathBuf::from(root.split("=/").next()?.replace('\\', ""));
+    let (package, file) = element.split_once('(')?;
+    let name = file.strip_suffix(".class")?;
+    if name.is_empty() || !folder.is_dir() {
+        return None;
+    }
+    Some((package.replace('.', "/"), name.to_owned()))
+}
+
+/// The project's source of `class` (`Name`, `Outer$Inner`, `FileKt`) in `package`
+/// (`/`-separated): a `.kt` / `.java` file of that name declaring the package. Build
+/// output and ignored files are skipped.
+pub(crate) fn project_class_source(root: &Path, package: &str, class: &str) -> Option<PathBuf> {
+    let outer = class.split('$').next().unwrap_or(class);
+    let mut names = vec![format!("{outer}.kt"), format!("{outer}.java")];
+    if let Some(file) = outer.strip_suffix("Kt").filter(|f| !f.is_empty()) {
+        names.push(format!("{file}.kt"));
+    }
+    let package = package.replace('/', ".");
+    let mut found: Vec<PathBuf> = ignore::WalkBuilder::new(root)
+        .filter_entry(|e| {
+            let output = matches!(e.file_name().to_str(), Some("target" | "build" | "out" | "node_modules"));
+            // A package may be named `build`: only outside source trees is it output.
+            !output || e.path().components().any(|c| c.as_os_str() == "src")
+        })
+        .build()
+        .flatten()
+        .filter(|e| e.file_type().is_some_and(|t| t.is_file()))
+        .filter(|e| e.file_name().to_str().is_some_and(|n| names.iter().any(|name| name == n)))
+        .map(|e| e.into_path())
+        .filter(|p| std::fs::read_to_string(p).is_ok_and(|text| declared_package(&text) == package))
+        .collect();
+    // The directory matching the package first, then by name order.
+    found.sort_by_key(|p| {
+        let dir = p.parent().map(|d| d.to_string_lossy().replace('\\', "/")).unwrap_or_default();
+        let name = p.file_name().and_then(|n| n.to_str()).unwrap_or_default();
+        (!dir.ends_with(&format!("/{}", package.replace('.', "/"))), names.iter().position(|n| n == name))
+    });
+    found.into_iter().next()
+}
+
+/// The `package` a Kotlin or Java file declares; empty for the default package.
+fn declared_package(text: &str) -> String {
+    text.lines()
+        .map(str::trim)
+        .find(|line| line.starts_with("package "))
+        .map(|line| line["package ".len()..].trim_end_matches(';').trim().replace('`', ""))
+        .unwrap_or_default()
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -414,6 +474,58 @@ mod tests {
         assert_eq!((reloaded.text.as_str(), reloaded.encoding.as_str()), (GBK_SAMPLE, "gbk"));
     }
 
+    #[test]
+    fn maps_class_folder_classes_to_project_sources() {
+        let dir = tempfile::tempdir().unwrap();
+        let root = dir.path();
+        let output = root.join(".cache/kotlin/main-0");
+        std::fs::create_dir_all(output.join("test001")).unwrap();
+        // As jdtls writes it: the class's source file name in the path, the library's
+        // classpath attributes after the folder.
+        let escaped = output.to_string_lossy().replace('/', "\\/");
+        let handle = format!("=demo/{escaped}=/ai.openidea.kotlin=/true=/<test001(Db.class");
+        let uri = format!("jdt://contents/main-0/test001/Db.kt?{}", utf8_percent_encode(&handle, PATH));
+        assert_eq!(folder_class(&uri), Some(("test001".into(), "Db".into())));
+        let plain = format!(
+            "jdt://contents/main-0/test001/Db.class?{}",
+            utf8_percent_encode(&format!("=demo/{escaped}<test001(Db.class"), PATH)
+        );
+        assert_eq!(folder_class(&plain), Some(("test001".into(), "Db".into())));
+        let nested = format!(
+            "jdt://contents/main-0/a.b/Db.kt?{}",
+            utf8_percent_encode(&format!("=demo/{escaped}<a.b(Db$Companion.class"), PATH)
+        );
+        assert_eq!(folder_class(&nested), Some(("a/b".into(), "Db$Companion".into())));
+        let jar = "jdt://contents/a.jar/p/C.class?=p/%5C/m2%5C/a.jar%3Cp%28C.class";
+        assert_eq!(folder_class(jar), None, "a dependency jar");
+        assert_eq!(folder_class(&uri.replace("main-0", "gone")), None);
+
+        let write = |path: &str, text: &str| {
+            let path = root.join(path);
+            std::fs::create_dir_all(path.parent().unwrap()).unwrap();
+            std::fs::write(path, text).unwrap();
+        };
+        write("src/main/kotlin/test001/Db.kt", "package test001\n\nclass Db\n");
+        write("src/main/kotlin/other/Db.kt", "package other\n\nclass Db\n");
+        write("target/generated/test001/Db.kt", "package test001\n\nclass Db\n");
+        write("src/main/kotlin/util/Strings.kt", "@file:JvmName(\"Strings\")\npackage util\n\nfun shout() = 1\n");
+        write("src/main/kotlin/com/x/build/Tool.kt", "package com.x.build\n\nclass Tool\n");
+        write("src/main/kotlin/flat/Elsewhere.kt", "");
+        write("src/main/kotlin/Loose.kt", "package flat\n\nobject Loose\n");
+        let source = |package: &str, class: &str| {
+            project_class_source(root, package, class).map(|p| p.strip_prefix(root).unwrap().to_owned())
+        };
+        assert_eq!(source("test001", "Db"), Some(PathBuf::from("src/main/kotlin/test001/Db.kt")));
+        assert_eq!(source("test001", "Db$Companion"), Some(PathBuf::from("src/main/kotlin/test001/Db.kt")));
+        assert_eq!(source("other", "Db"), Some(PathBuf::from("src/main/kotlin/other/Db.kt")));
+        assert_eq!(source("util", "StringsKt"), Some(PathBuf::from("src/main/kotlin/util/Strings.kt")));
+        assert_eq!(source("com/x/build", "Tool"), Some(PathBuf::from("src/main/kotlin/com/x/build/Tool.kt")));
+        assert_eq!(source("flat", "Loose"), Some(PathBuf::from("src/main/kotlin/Loose.kt")), "any directory");
+        assert_eq!(source("test001", "Missing"), None);
+        assert_eq!(declared_package("package a.b.c;\n"), "a.b.c");
+        assert_eq!(declared_package("class A"), "");
+    }
+
     #[test]
     fn locates_declarations_in_kotlin_and_java_sources() {
         let at = |text: &str, name: &str| {

crates/ide-lsp/src/server.rs

@@ -658,6 +658,24 @@ impl Server {
         }
     }
 
+    /// Waits until no `$/progress` task is active, background work included (jdtls' builds,
+    /// rust-analyzer's `cargo check`), unlike [`Server::wait_indexed`]; false on timeout or
+    /// cancellation.
+    pub async fn wait_idle(&self, timeout: Duration, cancel: &CancellationToken) -> bool {
+        let deadline = tokio::time::Instant::now() + timeout;
+        loop {
+            let notified = self.phase_notify.notified();
+            if !self.is_busy() || self.running().is_none() {
+                return !self.is_busy();
+            }
+            tokio::select! {
+                () = notified => {}
+                () = tokio::time::sleep_until(deadline) => return !self.is_busy(),
+                () = cancel.cancelled() => return false,
+            }
+        }
+    }
+
     // ---- transiently opened files ----
 
     /// Registers a holder of the transient file `path` on instance `generation`;

crates/ide-lsp/tests/mock_server.rs

@@ -2178,6 +2178,57 @@ async fn missing_server_reports_once() {
     assert!(h.mgr.semantic_tokens(doc).await.unwrap().is_none());
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn checking_a_document_saves_it_and_waits_for_fresh_diagnostics() {
+    let h = harness(&[("mock", incremental_caps())]);
+    let s = h.launcher.state("mock");
+    let (doc, path) = h.open("a.mk", "bad\n");
+    h.wait_status("mock", ServerStatus::Ready).await;
+    // The server answers the save with a publish, as an on-save check (`cargo check`) does.
+    let (server, uri) = (s.clone(), uri_of(&path));
+    let publisher = tokio::spawn(async move {
+        eventually(|| !server.notified("textDocument/didSave").is_empty()).await;
+        let diag = json!({ "range": {"start":{"line":0,"character":0},"end":{"line":0,"character":3}},
+                           "severity": 1, "message": "on save" });
+        server.peer().notify("textDocument/publishDiagnostics", json!({ "uri": uri, "diagnostics": [diag] })).unwrap();
+    });
+    let cancel = CancellationToken::new();
+    let changed = Some(std::time::Instant::now());
+    let check = h.mgr.check_document(doc, changed, Duration::from_secs(20), &cancel).await.unwrap();
+    publisher.await.unwrap();
+    assert_eq!(check.diagnostics.iter().map(|d| d.message.as_str()).collect::<Vec<_>>(), ["on save"]);
+    assert!(check.servers[0].checked && !check.servers[0].incomplete, "{:?}", check.servers);
+
+    // A change the server never answered: what it has is reported as not fresh.
+    let changed = Some(std::time::Instant::now());
+    let stale = h.mgr.check_document(doc, changed, Duration::from_millis(800), &cancel).await.unwrap();
+    assert!(stale.servers[0].checked && stale.servers[0].incomplete, "{:?}", stale.servers);
+    assert_eq!(stale.diagnostics.len(), 1);
+}
+
+#[tokio::test(flavor = "multi_thread")]
+async fn checking_a_document_reports_servers_that_cannot_check() {
+    let cancel = CancellationToken::new();
+    let h = harness(&[("ghost", json!({}))]);
+    h.launcher.state("ghost").missing.store(true, Ordering::SeqCst);
+    let (doc, _) = h.open("a.mk", "x");
+    h.wait_status("ghost", ServerStatus::Missing).await;
+    let check = h.mgr.check_document(doc, None, Duration::from_secs(5), &cancel).await.unwrap();
+    assert!(check.diagnostics.is_empty());
+    let s = &check.servers[0];
+    assert_eq!((s.name.as_str(), s.status, s.checked), ("ghost", ServerStatus::Missing, false));
+    assert_eq!(s.message.as_deref(), Some("install ghost"));
+
+    let h = harness(&[("mock", incremental_caps())]);
+    h.mgr.set_config_hook(Box::new(|cfg, _| cfg.launch_error = Some("needs JDK 21".into())));
+    let (doc, _) = h.open("a.mk", "x");
+    h.wait_status("mock", ServerStatus::Misconfigured).await;
+    let check = h.mgr.check_document(doc, None, Duration::from_secs(5), &cancel).await.unwrap();
+    assert_eq!(check.servers[0].status, ServerStatus::Misconfigured);
+    assert!(check.servers[0].message.as_deref().is_some_and(|m| m.contains("needs JDK 21")), "{:?}", check.servers);
+    assert!(!check.servers[0].checked);
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn launch_error_fails_without_starting_the_server() {
     let h = harness(&[("mock", incremental_caps())]);

crates/ide-mcp/src/server.rs

@@ -3,17 +3,39 @@
 use crate::discovery::Discovery;
 use crate::{CancellationToken, PROJECT_HEADER, ToolRegistry, protocol};
 use bytes::Bytes;
-use http_body_util::{BodyExt, Full, Limited};
-use hyper::body::Incoming;
+use http_body_util::{BodyExt, Either, Full, Limited};
+use hyper::body::{Frame, Incoming};
 use hyper::header::{self, HeaderMap, HeaderValue};
 use hyper::{Method, Request, Response, StatusCode};
+use serde_json::{Value, json};
 use std::convert::Infallible;
 use std::path::{Path, PathBuf};
+use std::pin::Pin;
 use std::sync::Arc;
+use std::task::{Context, Poll};
+use std::time::Duration;
 use tokio::sync::watch;
+use tokio::task::{JoinError, JoinHandle};
+use tokio_util::sync::DropGuard;
 
 /// Largest request body.
 const MAX_BODY: usize = 8 << 20;
+/// A call still running after this long is answered on an event stream (when the client
+/// takes one), so that it can take as long as it needs: clients give up on a POST whose
+/// response has not started (Claude Code after a minute).
+#[cfg(not(test))]
+const STREAM_AFTER: Duration = Duration::from_secs(1);
+#[cfg(test)]
+const STREAM_AFTER: Duration = Duration::from_millis(100);
+/// How often a streamed call reports that it is still running: progress notifications reset
+/// the client's idle timeout (Claude Code's is five minutes).
+#[cfg(not(test))]
+const HEARTBEAT: Duration = Duration::from_secs(15);
+#[cfg(test)]
+const HEARTBEAT: Duration = Duration::from_millis(100);
+
+type Handled = Result<Option<Value>, Value>;
+type Body = Either<Full<Bytes>, EventStream>;
 
 struct Shared {
     registry: Arc<dyn ToolRegistry>,
@@ -140,15 +162,11 @@ async fn accept(listener: tokio::net::TcpListener, shared: Arc<Shared>, mut stop
     }
 }
 
-async fn serve(
-    req: Request<Incoming>,
-    shared: Arc<Shared>,
-    scope: String,
-) -> Result<Response<Full<Bytes>>, Infallible> {
+async fn serve(req: Request<Incoming>, shared: Arc<Shared>, scope: String) -> Result<Response<Body>, Infallible> {
     Ok(respond(req, &shared, scope).await)
 }
 
-type Reply = Response<Full<Bytes>>;
+type Reply = Response<Body>;
 
 async fn respond(req: Request<Incoming>, shared: &Arc<Shared>, scope: String) -> Reply {
     if req.uri().path() != "/mcp" {
@@ -163,7 +181,7 @@ async fn respond(req: Request<Incoming>, shared: &Arc<Shared>, scope: String) ->
         return response;
     }
     if req.method() != Method::POST {
-        // No server-sent event streams: every answer is in the POST's response.
+        // No stream of server-initiated messages: every answer is in the POST's response.
         let mut response = plain(StatusCode::METHOD_NOT_ALLOWED, "only POST");
         response.headers_mut().insert(header::ALLOW, HeaderValue::from_static("POST"));
         return response;
@@ -175,25 +193,41 @@ async fn respond(req: Request<Incoming>, shared: &Arc<Shared>, scope: String) ->
     }
     let scope = req.headers().get("mcp-session-id").and_then(|v| v.to_str().ok()).unwrap_or(&scope).to_owned();
     let project = project_of(&req);
+    let streams =
+        req.headers().get_all(header::ACCEPT).iter().any(|v| v.to_str().is_ok_and(|v| v.contains("text/event-stream")));
     let body = match Limited::new(req.into_body(), MAX_BODY).collect().await {
         Ok(body) => body.to_bytes(),
         Err(e) => return plain(StatusCode::PAYLOAD_TOO_LARGE, &format!("request body: {e}")),
     };
-    let initializing = serde_json::from_slice::<serde_json::Value>(&body)
-        .is_ok_and(|m| m.get("method").and_then(|v| v.as_str()) == Some("initialize"));
+    let message = serde_json::from_slice::<Value>(&body).ok();
+    let initializing = message.as_ref().is_some_and(|m| m.get("method").and_then(|v| v.as_str()) == Some("initialize"));
+    let id = message.as_ref().and_then(|m| m.get("id")).cloned().unwrap_or(Value::Null);
+    let progress_token = message.as_ref().and_then(|m| m.pointer("/params/_meta/progressToken")).cloned();
     let response_scope = scope.clone();
     let registry = shared.registry.clone();
     let shared = shared.clone();
     let cancel = shared.cancel.child_token();
-    let _guard = cancel.clone().drop_guard();
-    let handled = tokio::task::spawn_blocking(move || {
+    // Cancels the call when the client goes away (the response is dropped).
+    let guard = cancel.clone().drop_guard();
+    let mut handled = tokio::task::spawn_blocking(move || {
         protocol::handle_body(registry.as_ref(), project.as_deref(), &body, &shared.requests, &scope, cancel)
-    })
-    .await;
+    });
+    if streams && !initializing {
+        match tokio::time::timeout(STREAM_AFTER, &mut handled).await {
+            Ok(done) => return answer(done, false, &response_scope),
+            Err(_) => return event_stream(handled, id, progress_token, guard),
+        }
+    }
+    let done = handled.await;
+    drop(guard);
+    answer(done, initializing, &response_scope)
+}
+
+fn answer(handled: Result<Handled, JoinError>, initializing: bool, scope: &str) -> Reply {
     match handled {
         Ok(Ok(Some(reply))) => {
             let mut response = json(StatusCode::OK, &reply);
-            if initializing && let Ok(value) = HeaderValue::from_str(&response_scope) {
+            if initializing && let Ok(value) = HeaderValue::from_str(scope) {
                 response.headers_mut().insert("mcp-session-id", value);
             }
             response
@@ -204,6 +238,71 @@ async fn respond(req: Request<Incoming>, shared: &Arc<Shared>, scope: String) ->
     }
 }
 
+/// Answers a call that is still running on an event stream: a progress notification every
+/// [`HEARTBEAT`] while it runs (a comment when the client gave no progress token), then its
+/// answer. The call is cancelled as soon as the client goes away.
+fn event_stream(mut handled: JoinHandle<Handled>, id: Value, token: Option<Value>, guard: DropGuard) -> Reply {
+    let (tx, rx) = tokio::sync::mpsc::channel::<Bytes>(4);
+    tokio::spawn(async move {
+        let _guard = guard;
+        let started = tokio::time::Instant::now();
+        let mut beat = tokio::time::interval_at(started + HEARTBEAT, HEARTBEAT);
+        loop {
+            tokio::select! {
+                done = &mut handled => {
+                    let reply = match done {
+                        Ok(Ok(Some(reply)) | Err(reply)) => reply,
+                        Ok(Ok(None)) => return,
+                        Err(e) => protocol::error_response(id, -32603, &format!("the request failed: {e}")),
+                    };
+                    let _ = tx.send(event(&reply)).await;
+                    return;
+                }
+                _ = beat.tick() => {
+                    let elapsed = started.elapsed();
+                    let still_running = match &token {
+                        Some(token) => event(&json!({
+                            "jsonrpc": "2.0",
+                            "method": "notifications/progress",
+                            "params": {
+                                "progressToken": token,
+                                "progress": elapsed.as_secs_f64(),
+                                "message": format!("running for {}s", elapsed.as_secs()),
+                            },
+                        })),
+                        None => Bytes::from_static(b": running\n\n"),
+                    };
+                    if tx.send(still_running).await.is_err() {
+                        return;
+                    }
+                }
+                _ = tx.closed() => return,
+            }
+        }
+    });
+    let mut response = Response::new(Either::Right(EventStream(rx)));
+    response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static("text/event-stream"));
+    response.headers_mut().insert(header::CACHE_CONTROL, HeaderValue::from_static("no-cache"));
+    response
+}
+
+/// One server-sent event carrying a JSON-RPC message.
+fn event(message: &Value) -> Bytes {
+    Bytes::from(format!("event: message\ndata: {message}\n\n"))
+}
+
+/// A `text/event-stream` body, written by [`event_stream`]'s task.
+pub(crate) struct EventStream(tokio::sync::mpsc::Receiver<Bytes>);
+
+impl hyper::body::Body for EventStream {
+    type Data = Bytes;
+    type Error = Infallible;
+
+    fn poll_frame(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Option<Result<Frame<Bytes>, Infallible>>> {
+        self.get_mut().0.poll_recv(cx).map(|data| data.map(|data| Ok(Frame::data(data))))
+    }
+}
+
 /// No `Origin` other than this server's own, and a loopback `Host`: a web
 /// page (DNS rebinding) can't reach the tools even before the token check.
 fn local_request(headers: &HeaderMap, port: u16) -> bool {
@@ -242,22 +341,22 @@ fn project_of(req: &Request<Incoming>) -> Option<String> {
     })
 }
 
-fn plain(status: StatusCode, text: &str) -> Response<Full<Bytes>> {
-    let mut response = Response::new(Full::new(Bytes::from(text.to_owned())));
+fn plain(status: StatusCode, text: &str) -> Reply {
+    let mut response = Response::new(Either::Left(Full::new(Bytes::from(text.to_owned()))));
     *response.status_mut() = status;
     response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static("text/plain; charset=utf-8"));
     response
 }
 
-fn json(status: StatusCode, value: &serde_json::Value) -> Response<Full<Bytes>> {
-    let mut response = Response::new(Full::new(Bytes::from(value.to_string())));
+fn json(status: StatusCode, value: &Value) -> Reply {
+    let mut response = Response::new(Either::Left(Full::new(Bytes::from(value.to_string()))));
     *response.status_mut() = status;
     response.headers_mut().insert(header::CONTENT_TYPE, HeaderValue::from_static("application/json"));
     response
 }
 
-fn empty(status: StatusCode) -> Response<Full<Bytes>> {
-    let mut response = Response::new(Full::new(Bytes::new()));
+fn empty(status: StatusCode) -> Reply {
+    let mut response = Response::new(Either::Left(Full::new(Bytes::new())));
     *response.status_mut() = status;
     response
 }
@@ -265,6 +364,134 @@ fn empty(status: StatusCode) -> Response<Full<Bytes>> {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use std::sync::atomic::{AtomicBool, Ordering};
+    use tokio::io::{AsyncReadExt, AsyncWriteExt};
+
+    /// `slow` sleeps `ms` milliseconds; `wait` runs until it is cancelled, which it records.
+    struct Slow(Arc<AtomicBool>);
+
+    impl ToolRegistry for Slow {
+        fn projects(&self) -> Vec<PathBuf> {
+            vec![PathBuf::from("/project")]
+        }
+        fn tools(&self, _: &Path) -> Result<Vec<crate::Tool>, String> {
+            Ok(Vec::new())
+        }
+        fn call(
+            &self,
+            _: &Path,
+            name: &str,
+            arguments: &str,
+            cancel: CancellationToken,
+        ) -> Result<String, crate::ToolCallError> {
+            if name == "wait" {
+                while !cancel.is_cancelled() {
+                    std::thread::sleep(Duration::from_millis(10));
+                }
+                self.0.store(true, Ordering::SeqCst);
+                return Err(crate::ToolCallError::Failed("cancelled".into()));
+            }
+            let ms = serde_json::from_str::<Value>(arguments).unwrap()["ms"].as_u64().unwrap();
+            std::thread::sleep(Duration::from_millis(ms));
+            Ok("done".into())
+        }
+    }
+
+    fn start() -> (McpServer, Arc<AtomicBool>) {
+        let cancelled = Arc::new(AtomicBool::new(false));
+        let registry = Arc::new(Slow(cancelled.clone()));
+        (McpServer::start(registry, None, &tokio::runtime::Handle::current()).unwrap(), cancelled)
+    }
+
+    fn call(name: &str, ms: u64, token: Option<&str>) -> Value {
+        let mut params = json!({ "name": name, "arguments": { "ms": ms } });
+        if let Some(token) = token {
+            params["_meta"] = json!({ "progressToken": token });
+        }
+        json!({ "jsonrpc": "2.0", "id": 3, "method": "tools/call", "params": params })
+    }
+
+    async fn send(server: &McpServer, accept: &str, body: &Value) -> tokio::net::TcpStream {
+        let body = body.to_string();
+        let port = server.port();
+        let mut stream = tokio::net::TcpStream::connect(("127.0.0.1", port)).await.unwrap();
+        let request = format!(
+            "POST /mcp HTTP/1.1\r\nHost: 127.0.0.1:{port}\r\nAuthorization: Bearer {}\r\nContent-Type: application/json\r\nAccept: {accept}\r\nContent-Length: {}\r\nConnection: close\r\n\r\n{body}",
+            server.token(),
+            body.len()
+        );
+        stream.write_all(request.as_bytes()).await.unwrap();
+        stream
+    }
+
+    /// The whole response, lowercased headers and the body as sent (chunked or not).
+    async fn exchange(server: &McpServer, accept: &str, body: &Value) -> (String, String) {
+        let mut out = String::new();
+        send(server, accept, body).await.read_to_string(&mut out).await.unwrap();
+        let (head, body) = out.split_once("\r\n\r\n").unwrap();
+        (head.to_ascii_lowercase(), body.to_owned())
+    }
+
+    fn events(body: &str) -> Vec<Value> {
+        body.lines().filter_map(|l| l.strip_prefix("data: ")).map(|d| serde_json::from_str(d).unwrap()).collect()
+    }
+
+    const BOTH: &str = "application/json, text/event-stream";
+
+    #[tokio::test(flavor = "multi_thread")]
+    async fn long_calls_are_answered_on_an_event_stream_that_reports_progress() {
+        let (server, _) = start();
+
+        let (head, body) = exchange(&server, BOTH, &call("slow", 0, Some("p"))).await;
+        assert!(head.contains("content-type: application/json"), "{head}");
+        assert_eq!(serde_json::from_str::<Value>(&body).unwrap()["result"]["content"][0]["text"], "done");
+
+        let (head, body) = exchange(&server, BOTH, &call("slow", 450, Some("p"))).await;
+        assert!(head.contains("content-type: text/event-stream"), "{head}");
+        let messages = events(&body);
+        let (answer, progress) = messages.split_last().unwrap();
+        assert_eq!(answer["id"], 3);
+        assert_eq!(answer["result"]["content"][0]["text"], "done");
+        assert!(progress.len() >= 2, "{body}");
+        for pair in progress.windows(2) {
+            assert!(pair[0]["params"]["progress"].as_f64() < pair[1]["params"]["progress"].as_f64(), "{body}");
+        }
+        for p in progress {
+            assert_eq!((&p["method"], &p["params"]["progressToken"]), (&json!("notifications/progress"), &json!("p")));
+        }
+
+        // Without a progress token, comments keep the stream going.
+        let (_, body) = exchange(&server, BOTH, &call("slow", 300, None)).await;
+        assert!(body.contains(": running"), "{body}");
+        assert_eq!(events(&body).len(), 1, "{body}");
+
+        // A client that takes only JSON waits for it.
+        let (head, body) = exchange(&server, "application/json", &call("slow", 300, Some("p"))).await;
+        assert!(head.contains("content-type: application/json"), "{head}");
+        assert_eq!(serde_json::from_str::<Value>(&body).unwrap()["id"], 3);
+    }
+
+    #[tokio::test(flavor = "multi_thread")]
+    async fn a_streamed_call_is_cancelled_when_the_client_goes_away() {
+        let (server, cancelled) = start();
+        let mut stream = send(&server, BOTH, &call("wait", 0, Some("p"))).await;
+        let mut head = Vec::new();
+        while !String::from_utf8_lossy(&head).contains("\r\n\r\n") {
+            let mut buf = [0u8; 1024];
+            let n = stream.read(&mut buf).await.unwrap();
+            assert!(n > 0, "the stream ended early");
+            head.extend_from_slice(&buf[..n]);
+        }
+        assert!(String::from_utf8_lossy(&head).to_ascii_lowercase().contains("text/event-stream"));
+        drop(stream);
+        tokio::time::timeout(Duration::from_secs(10), async {
+            while !cancelled.load(Ordering::SeqCst) {
+                tokio::time::sleep(Duration::from_millis(20)).await;
+            }
+        })
+        .await
+        .expect("the call was cancelled");
+    }
 
     #[test]
     fn only_loopback_hosts_and_origins_of_this_server_pass() {

crates/ide-mcp/src/stdio.rs

@@ -35,7 +35,8 @@ pub fn run(discovery: &Path, project: Option<PathBuf>) -> i32 {
 }
 
 /// Relays each line of `input` (a JSON-RPC message or batch) to the IDE and
-/// writes its answer, if any, as one line to `output`.
+/// writes what it answers, if anything, one message per line to `output`: the
+/// answer, and before it the progress notifications of a long call.
 pub async fn bridge<R, W>(discovery: &Path, project: &Path, input: R, mut output: W) -> std::io::Result<()>
 where
     R: AsyncBufRead + Unpin,
@@ -44,23 +45,37 @@ where
     let scope = crate::server::new_token()?;
     let mut lines = input.lines();
     let mut pending = tokio::task::JoinSet::new();
+    let (sent, mut received) = tokio::sync::mpsc::unbounded_channel::<Value>();
     let mut eof = false;
     loop {
+        if eof && pending.is_empty() && received.is_empty() {
+            break;
+        }
         let reply = tokio::select! {
             line = lines.next_line(), if !eof => {
                 let Some(line) = line? else { eof = true; continue };
                 if line.trim().is_empty() { continue; }
                 match serde_json::from_str::<Value>(&line) {
                     Ok(message) => {
-                        let (discovery, project, scope) = (discovery.to_owned(), project.to_owned(), scope.clone());
-                        pending.spawn(async move { relay(&discovery, &project, &message, &scope).await });
+                        let (discovery, project, scope, sent) =
+                            (discovery.to_owned(), project.to_owned(), scope.clone(), sent.clone());
+                        pending.spawn(async move {
+                            if let Some(reply) = relay(&discovery, &project, &message, &scope, &sent).await {
+                                let _ = sent.send(reply);
+                            }
+                        });
                         continue;
                     }
                     Err(e) => Some(error_response(Value::Null, -32700, &format!("not JSON: {e}"))),
                 }
             }
-            reply = pending.join_next(), if !pending.is_empty() => match reply { Some(reply) => reply.map_err(std::io::Error::other)?, None => None },
-            else => break,
+            Some(message) = received.recv() => Some(message),
+            done = pending.join_next(), if !pending.is_empty() => {
+                if let Some(Err(e)) = done {
+                    return Err(std::io::Error::other(e));
+                }
+                continue;
+            }
         };
         if let Some(reply) = reply {
             output.write_all(reply.to_string().as_bytes()).await?;
@@ -72,15 +87,24 @@ where
 }
 
 /// The IDE's answer to `message`, or an error response for each request in
-/// it when the IDE can't be reached.
-async fn relay(discovery: &Path, project: &Path, message: &Value, scope: &str) -> Option<Value> {
-    let failure = match post(discovery, project, message, scope).await {
-        Ok((StatusCode::ACCEPTED, _)) => return None,
-        Ok((_, body)) if !body.is_empty() => match serde_json::from_slice::<Value>(&body) {
+/// it when the IDE can't be reached. An answer on an event stream goes to `sent`
+/// with the messages before it.
+async fn relay(
+    discovery: &Path,
+    project: &Path,
+    message: &Value,
+    scope: &str,
+    sent: &tokio::sync::mpsc::UnboundedSender<Value>,
+) -> Option<Value> {
+    let failure = match post(discovery, project, message, scope, sent).await {
+        Ok(Answer::Streamed { answered: true }) => return None,
+        Ok(Answer::Streamed { answered: false }) => "OpenIDEA's answer ended early".to_owned(),
+        Ok(Answer::Body(StatusCode::ACCEPTED, _)) => return None,
+        Ok(Answer::Body(_, body)) if !body.is_empty() => match serde_json::from_slice::<Value>(&body) {
             Ok(reply) => return Some(reply),
             Err(_) => String::from_utf8_lossy(&body).trim().to_owned(),
         },
-        Ok((status, _)) => format!("OpenIDEA answered {status}"),
+        Ok(Answer::Body(status, _)) => format!("OpenIDEA answered {status}"),
         Err(e) => e,
     };
     let errors: Vec<Value> = requests(message).into_iter().map(|id| error_response(id, NOT_OPEN, &failure)).collect();
@@ -100,9 +124,23 @@ fn requests(message: &Value) -> Vec<Value> {
     }
 }
 
+enum Answer {
+    Body(StatusCode, Bytes),
+    /// The messages of an event stream went to the channel; `answered`: one was a response.
+    Streamed {
+        answered: bool,
+    },
+}
+
 /// POSTs `message` to the server in the discovery file; a message for the
 /// user when that fails.
-async fn post(discovery: &Path, project: &Path, message: &Value, scope: &str) -> Result<(StatusCode, Bytes), String> {
+async fn post(
+    discovery: &Path,
+    project: &Path,
+    message: &Value,
+    scope: &str,
+    sent: &tokio::sync::mpsc::UnboundedSender<Value>,
+) -> Result<Answer, String> {
     let not_running = || {
         format!(
             "OpenIDEA's MCP server is not running. Start OpenIDEA, open {} in it, and turn on Settings › Agents › MCP Server",
@@ -125,6 +163,60 @@ async fn post(discovery: &Path, project: &Path, message: &Value, scope: &str) ->
         .map_err(|e| e.to_string())?;
     let response = sender.send_request(request).await.map_err(|e| format!("cannot reach OpenIDEA: {e}"))?;
     let status = response.status();
-    let body = response.into_body().collect().await.map_err(|e| format!("OpenIDEA's answer: {e}"))?.to_bytes();
-    Ok((status, body))
+    let streamed = response
+        .headers()
+        .get(header::CONTENT_TYPE)
+        .is_some_and(|v| v.to_str().is_ok_and(|v| v.starts_with("text/event-stream")));
+    let mut body = response.into_body();
+    if !streamed {
+        let body = body.collect().await.map_err(|e| format!("OpenIDEA's answer: {e}"))?.to_bytes();
+        return Ok(Answer::Body(status, body));
+    }
+    let (mut buffer, mut answered) = (Vec::new(), false);
+    while let Some(frame) = body.frame().await {
+        let frame = frame.map_err(|e| format!("OpenIDEA's answer: {e}"))?;
+        let Ok(data) = frame.into_data() else { continue };
+        buffer.extend_from_slice(&data);
+        for data in take_events(&mut buffer) {
+            if let Ok(message) = serde_json::from_str::<Value>(&data) {
+                answered |= message.get("method").is_none();
+                let _ = sent.send(message);
+            }
+        }
+    }
+    Ok(Answer::Streamed { answered })
+}
+
+/// The `data` of each complete server-sent event at the start of `buffer`, which keeps
+/// the rest. Comments and other fields are skipped.
+fn take_events(buffer: &mut Vec<u8>) -> Vec<String> {
+    let mut events = Vec::new();
+    while let Some(end) = buffer.windows(2).position(|w| w == b"\n\n") {
+        let block: Vec<u8> = buffer.drain(..end + 2).collect();
+        let block = String::from_utf8_lossy(&block).replace("\r\n", "\n");
+        let data: Vec<&str> = block
+            .lines()
+            .filter_map(|line| line.strip_prefix("data:"))
+            .map(|d| d.strip_prefix(' ').unwrap_or(d))
+            .collect();
+        if !data.is_empty() {
+            events.push(data.join("\n"));
+        }
+    }
+    events
+}
+
+#[cfg(test)]
+mod tests {
+    use super::take_events;
+
+    #[test]
+    fn events_are_taken_whole_and_comments_skipped() {
+        let mut buffer = b": running\n\nevent: message\ndata: {\"a\":1}\n\nevent: message\ndata: {\"b\"".to_vec();
+        assert_eq!(take_events(&mut buffer), ["{\"a\":1}"]);
+        assert_eq!(buffer, b"event: message\ndata: {\"b\"");
+        buffer.extend_from_slice(b":2}\n\n");
+        assert_eq!(take_events(&mut buffer), ["{\"b\":2}"]);
+        assert!(buffer.is_empty());
+    }
 }

crates/ide-mcp/tests/server.rs

@@ -39,6 +39,10 @@ impl ToolRegistry for Registry {
         match name {
             "echo" if args["text"] == "fail" => Err(ToolCallError::Failed("it failed".into())),
             "echo" => Ok(format!("{} in {}", args["text"].as_str().unwrap_or(""), project.display())),
+            "sleep" => {
+                std::thread::sleep(std::time::Duration::from_millis(args["ms"].as_u64().unwrap()));
+                Ok("slept".into())
+            }
             _ => Err(ToolCallError::UnknownTool(format!("no tool {name:?}"))),
         }
     }
@@ -252,6 +256,20 @@ async fn the_stdio_bridge_relays_lines_and_explains_a_missing_ide() {
     assert!(reply["error"]["message"].as_str().unwrap().contains("MCP server is not running"), "{reply}");
 }
 
+#[tokio::test(flavor = "multi_thread")]
+async fn the_stdio_bridge_relays_a_long_call_answered_on_an_event_stream() {
+    let s = setup();
+    let call = json!({ "jsonrpc": "2.0", "id": 4, "method": "tools/call",
+        "params": { "name": "sleep", "arguments": { "ms": 1500 }, "_meta": { "progressToken": 4 } } });
+    let mut output = Vec::new();
+    stdio::bridge(&s.discovery, &s.project, format!("{call}\n").as_bytes(), &mut output).await.unwrap();
+    let replies: Vec<Value> =
+        String::from_utf8(output).unwrap().lines().map(|l| serde_json::from_str(l).unwrap()).collect();
+    let answer = replies.last().unwrap();
+    assert_eq!(answer["id"], 4, "{replies:?}");
+    assert_eq!(answer["result"]["content"][0]["text"], "slept");
+}
+
 #[tokio::test(flavor = "multi_thread")]
 async fn routing_an_argument_overrides_the_header_and_ambiguity_lists_projects() {
     struct Many(Vec<PathBuf>);

crates/ide-plugin/Cargo.toml

@@ -23,5 +23,5 @@ wasmtime-wasi = { version = "49.0.4", default-features = false, features = ["p2"
 
 [dev-dependencies]
 tempfile.workspace = true
-tokio = { workspace = true, features = ["rt-multi-thread", "macros", "time"] }
+tokio = { workspace = true, features = ["rt-multi-thread", "macros", "time", "net"] }
 wat = "1.258"

crates/ide-plugin/src/runtime.rs

@@ -55,7 +55,7 @@ use views_bindings::exports::openidea::plugin::view_provider as wit_view;
 use views_bindings::openidea::plugin::view_types as wit_vt;
 
 /// The API version of the world above, `major.minor` of [`host_api`].
-pub const API_VERSION: &str = "1.6";
+pub const API_VERSION: &str = "1.7";
 const EPOCH_TICK: Duration = Duration::from_millis(10);
 pub(crate) const MAX_TEXT: usize = 1 << 20;
 pub(crate) const MAX_TITLE: usize = 256;
@@ -170,6 +170,11 @@ pub trait HostApi: Send + Sync {
         let _ = (client, tab, cancel, timeout);
         Err(HostError::Failed("content tabs unavailable".into()))
     }
+    /// Opens a diff of two texts in the invoking window.
+    fn open_diff(&self, client: &str, diff: crate::ContentDiff, file_name: Option<String>) -> Result<(), HostError> {
+        let _ = (client, diff, file_name);
+        Err(HostError::Failed("diffs unavailable".into()))
+    }
     /// Answers a content action in the invoking window.
     fn reply_content_tab(&self, client: &str, request: &str, reply: crate::ContentTabReply) -> Result<(), HostError> {
         let _ = (client, request, reply);
@@ -365,14 +370,7 @@ pub trait HostApi: Send + Sync {
     }
     /// The most specific open project containing a document (including a new file).
     fn project_of(&self, path: &Path) -> Option<std::path::PathBuf> {
-        if !path.is_absolute() {
-            return None;
-        }
-        let real = crate::resolve_real(path);
-        self.projects()
-            .into_iter()
-            .filter(|root| real.starts_with(crate::resolve_real(root)))
-            .max_by_key(|root| root.components().count())
+        crate::sandbox::innermost_root(self.projects(), path)
     }
 
     /// Searches the current in-memory index of an open project.

crates/ide-plugin/src/sandbox.rs

@@ -1,7 +1,9 @@
 //! Capability checks for host functions that touch the file system.
 
+use ide_core::real_path::reaches_git_dir;
+pub use ide_core::real_path::resolve_real;
 use ide_extension::Capability;
-use std::path::{Path, PathBuf};
+use std::path::{Component, Path, PathBuf, Prefix};
 
 /// Largest file `read-file` returns.
 /// The most entries `fs.read-dir` hands over: the same cap as `find-files`.
@@ -11,53 +13,114 @@ pub const MAX_READ_BYTES: u64 = 16 << 20;
 /// The largest file s.write may write, in bytes.
 pub const MAX_WRITE_BYTES: usize = 16 << 20;
 
-/// The canonical `root` and the absolute form of `path` (absolute, or
-/// relative to `root`) — before any symlink or existence check.
-fn joined_path(root: &Path, path: &str) -> Result<(PathBuf, PathBuf), String> {
+/// What a requested path is, judged from its text alone — before anything opens it. On
+/// Windows even resolving a path opens it, and opening a network or pipe path connects to
+/// that host or pipe, so every resolver asks this first and checks the real path after.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum Lexical {
+    /// A local path, or a network path under one of the allowed bases.
+    Resolvable,
+    /// A network path outside every allowed base.
+    Outside,
+    /// A device, pipe or file stream, which is never a file a plugin may use.
+    Refused,
+}
+
+/// Judges `path` against `bases` (absolute paths a resolver allows) from the text alone.
+fn judge(path: &Path, bases: &[&Path]) -> Lexical {
+    let Some((parts, remote)) = lexical_parts(path) else {
+        return Lexical::Refused;
+    };
+    let under =
+        |base: &&Path| base.is_absolute() && lexical_parts(base).is_some_and(|(base, _)| parts.starts_with(&base));
+    if remote && !bases.iter().any(under) { Lexical::Outside } else { Lexical::Resolvable }
+}
+
+/// `path` split into comparable parts, `.` and `..` applied, a verbatim drive or share
+/// spelled like the plain one and, on Windows, case-folded; with whether it names a network
+/// location. `None` for a device or pipe (`\\.\…`, `\\?\GLOBALROOT\…`, `NUL`, `COM1`) or an
+/// NTFS stream (`a.txt:s`).
+fn lexical_parts(path: &Path) -> Option<(Vec<String>, bool)> {
+    let mut parts = Vec::new();
+    let mut remote = false;
+    let mut anchored = 0;
+    for part in path.components() {
+        match part {
+            Component::Prefix(prefix) => {
+                parts.push(match prefix.kind() {
+                    Prefix::Disk(drive) | Prefix::VerbatimDisk(drive) => format!("{}:", char::from(drive)),
+                    Prefix::UNC(server, share) | Prefix::VerbatimUNC(server, share) => {
+                        remote = true;
+                        format!(r"\\{}\{}", server.to_string_lossy(), share.to_string_lossy())
+                    }
+                    Prefix::Verbatim(_) | Prefix::DeviceNS(_) => return None,
+                });
+                anchored = parts.len();
+            }
+            Component::RootDir => {
+                parts.push(std::path::MAIN_SEPARATOR_STR.to_owned());
+                anchored = parts.len();
+            }
+            Component::CurDir => {}
+            Component::ParentDir => {
+                if parts.len() > anchored {
+                    parts.pop();
+                }
+            }
+            Component::Normal(name) => {
+                let name = name.to_string_lossy();
+                if cfg!(windows) && (name.contains(':') || names_device(&name)) {
+                    return None;
+                }
+                parts.push(name.into_owned());
+            }
+        }
+    }
+    if cfg!(windows) {
+        parts.iter_mut().for_each(|part| *part = part.to_lowercase());
+    }
+    Some((parts, remote))
+}
+
+/// A name Windows opens as a device in every folder (`NUL`, `COM1`, `con.txt`): what comes
+/// before the first `.`, trailing spaces ignored.
+fn names_device(name: &str) -> bool {
+    let stem = name.split('.').next().unwrap_or_default().trim_end_matches(' ').to_ascii_uppercase();
+    match stem.as_str() {
+        "CON" | "PRN" | "AUX" | "NUL" | "CONIN$" | "CONOUT$" => true,
+        _ => stem.strip_prefix("COM").or_else(|| stem.strip_prefix("LPT")).is_some_and(|number| {
+            matches!(number, "0" | "1" | "2" | "3" | "4" | "5" | "6" | "7" | "8" | "9" | "¹" | "²" | "³")
+        }),
+    }
+}
+
+fn refused(path: &str) -> String {
+    format!("{path}: devices, pipes and file streams are not allowed")
+}
+
+/// The canonical `root` and the absolute form of `path` (absolute, or relative to `root`) —
+/// before any symlink or existence check — when [`judge`] lets it be resolved inside `root`.
+/// `Ok(None)` for a network path outside `root`.
+fn joined_path(root: &Path, path: &str) -> Result<Option<(PathBuf, PathBuf)>, String> {
     if path.is_empty() {
         return Err("empty path".into());
     }
-    let root = dunce::canonicalize(root).map_err(|e| format!("project root unavailable: {e}"))?;
+    let real_root = dunce::canonicalize(root).map_err(|e| format!("project root unavailable: {e}"))?;
     let requested = Path::new(path);
-    let joined = if requested.is_absolute() { requested.to_path_buf() } else { root.join(requested) };
-    Ok((root, joined))
-}
-
-/// `joined` after `..`/symlink resolution as far as the file system allows:
-/// the canonical path when it exists, else the canonicalized deepest existing
-/// ancestor with the still-missing tail resolved textually — so the location
-/// of a missing path is still judged where it would really land.
-pub fn resolve_real(joined: &Path) -> PathBuf {
-    let mut tail = Vec::new();
-    let mut candidate = joined.to_path_buf();
-    let mut real = loop {
-        match dunce::canonicalize(&candidate) {
-            Ok(real) => break real,
-            Err(_) => {
-                let Some(last) = candidate.components().next_back() else {
-                    return joined.to_path_buf();
-                };
-                tail.push(last.as_os_str().to_owned());
-                if !candidate.pop() {
-                    return joined.to_path_buf();
-                }
-            }
-        }
-    };
-    for part in tail.iter().rev() {
-        if part == ".." {
-            real.pop();
-        } else if part != "." {
-            real.push(part);
-        }
+    let joined = if requested.is_absolute() { requested.to_path_buf() } else { real_root.join(requested) };
+    match judge(&joined, &[root, &real_root]) {
+        Lexical::Resolvable => Ok(Some((real_root, joined))),
+        Lexical::Outside => Ok(None),
+        Lexical::Refused => Err(refused(path)),
     }
-    real
 }
 
 /// Resolves `path` (absolute, or relative to `root`) and checks that the real
 /// path — after following `..` and symlinks — stays inside `root`.
 pub fn resolve_in_root(root: &Path, path: &str) -> Result<PathBuf, String> {
-    let (root, joined) = joined_path(root, path)?;
+    let Some((root, joined)) = joined_path(root, path)? else {
+        return Err(format!("{path}: access outside the project root is not allowed"));
+    };
     let real = dunce::canonicalize(&joined).map_err(|_| format!("{path}: no such file"))?;
     if !real.starts_with(&root) {
         return Err(format!("{path}: access outside the project root is not allowed"));
@@ -93,7 +156,9 @@ pub fn resolve_in_roots(roots: &[PathBuf], path: &str) -> Result<PathBuf, String
 /// callers distinguish "outside" from "absent". Existing symlinks are
 /// followed; a missing tail is judged at its would-be location.
 pub fn inside_root(root: &Path, path: &str) -> Result<bool, String> {
-    let (root, joined) = joined_path(root, path)?;
+    let Some((root, joined)) = joined_path(root, path)? else {
+        return Ok(false);
+    };
     Ok(resolve_real(&joined).starts_with(&root))
 }
 
@@ -114,36 +179,40 @@ pub fn inside_roots(roots: &[PathBuf], path: &str) -> Result<bool, String> {
     Ok(false)
 }
 
+/// The most specific of `roots` containing `path` (absolute, and possibly not existing yet),
+/// judged where it really lands. A network path outside every root is not resolved at all.
+pub(crate) fn innermost_root(roots: Vec<PathBuf>, path: &Path) -> Option<PathBuf> {
+    if !path.is_absolute() {
+        return None;
+    }
+    let roots: Vec<(PathBuf, PathBuf)> = roots
+        .into_iter()
+        .map(|root| {
+            let real = resolve_real(&root);
+            (root, real)
+        })
+        .collect();
+    let bases: Vec<&Path> = roots.iter().flat_map(|(root, real)| [root.as_path(), real.as_path()]).collect();
+    if judge(path, &bases) != Lexical::Resolvable {
+        return None;
+    }
+    let real = resolve_real(path);
+    roots
+        .into_iter()
+        .filter(|(_, root)| real.starts_with(root))
+        .map(|(root, _)| root)
+        .max_by_key(|root| root.components().count())
+}
+
 /// Like [`resolve_in_root`] for a path that may not exist yet (a file about to
 /// be created) or that names a symlink itself (to delete or rename it): the
 /// directory part is resolved through symlinks, the final name is kept as is,
 /// and the result must stay inside `root`.
-/// Whether a path (relative to the project root) goes through git's own `.git` folder or file.
-/// git runs what it finds in `.git` (hooks, `gpg.program`, filters), so a content write must
-/// never reach it. Names are normalized for trailing dots and spaces and NTFS stream suffixes;
-/// the caller also checks the short-name-resolved path via [`resolve_real`].
-pub fn names_git_dir(rel: &Path) -> bool {
-    rel.components().any(|part| {
-        let name = part.as_os_str().to_string_lossy();
-        let name = name.split(':').next().unwrap_or_default().trim_end_matches(['.', ' ']);
-        name.eq_ignore_ascii_case(".git")
-    })
-}
-
-/// A resolved write destination that reaches git's own `.git` metadata, judged by the name
-/// given and by the name the file system resolves it to.
-fn reaches_git_dir(root: &Path, real: &Path) -> bool {
-    real.strip_prefix(root).is_ok_and(names_git_dir) || resolve_real(real).strip_prefix(root).is_ok_and(names_git_dir)
-}
-
 pub fn resolve_new_in_root(root: &Path, path: &str) -> Result<PathBuf, String> {
     let outside = || format!("{path}: access outside the project root is not allowed");
-    if path.is_empty() {
-        return Err("empty path".into());
-    }
-    let root = dunce::canonicalize(root).map_err(|e| format!("project root unavailable: {e}"))?;
-    let requested = Path::new(path);
-    let joined = if requested.is_absolute() { requested.to_path_buf() } else { root.join(requested) };
+    let Some((root, joined)) = joined_path(root, path)? else {
+        return Err(outside());
+    };
     let mut lexical = PathBuf::new();
     for part in joined.components() {
         match part {
@@ -181,7 +250,9 @@ pub fn resolve_new_in_root(root: &Path, path: &str) -> Result<PathBuf, String> {
 /// Resolves a content write's destination, including existing and dangling
 /// symlinks in the final component. Entry operations use [`resolve_new_in_root`].
 pub fn resolve_writable_in_root(root: &Path, path: &str) -> Result<PathBuf, String> {
-    let (root, joined) = joined_path(root, path)?;
+    let Some((root, joined)) = joined_path(root, path)? else {
+        return Err(format!("{path}: access outside the project root is not allowed"));
+    };
     let real = resolve_write_target(&joined, 40).map_err(|e| format!("{path}: {e}"))?;
     if !real.starts_with(&root) {
         return Err(format!("{path}: access outside the project root is not allowed"));
@@ -346,6 +417,22 @@ fn resolve(granted: &[Capability], path: &str, wanted: Wanted) -> Result<PathBuf
     if !asked.is_absolute() {
         return Err(Refusal::Invalid(format!("{path}: use an absolute path (or ~/…)")));
     }
+    let bases: Vec<PathBuf> = granted
+        .iter()
+        .filter_map(|grant| match (wanted, grant) {
+            (Wanted::Read, Capability::FsRead(base)) | (Wanted::Write, Capability::FsWrite(base)) => {
+                Some(expand_tilde(base))
+            }
+            _ => None,
+        })
+        .flat_map(|base| [dunce::canonicalize(&base).ok(), Some(base)])
+        .flatten()
+        .collect();
+    match judge(&asked, &bases.iter().map(PathBuf::as_path).collect::<Vec<_>>()) {
+        Lexical::Resolvable => {}
+        Lexical::Outside => return Err(Refusal::Denied(wanted.capability(strip_verbatim(&asked)).to_string())),
+        Lexical::Refused => return Err(Refusal::Invalid(refused(path))),
+    }
     let real = match wanted {
         Wanted::Read => dunce::canonicalize(&asked).map_err(|_| Refusal::Invalid(format!("{path}: no such file")))?,
         Wanted::Write => dunce::canonicalize(&asked)
@@ -399,6 +486,7 @@ fn strip_verbatim(path: &Path) -> String {
 #[cfg(test)]
 mod tests {
     use super::*;
+    use ide_core::real_path::names_git_dir;
 
     #[cfg(windows)]
     #[test]
@@ -894,4 +982,127 @@ mod tests {
         );
         assert_eq!(expand_tilde("relative/x"), PathBuf::from("relative/x"));
     }
+
+    /// Resolving a path must not open what it names before the path is known to be allowed:
+    /// on Windows, opening a pipe or network path (even only to canonicalize it) connects to
+    /// that pipe or host. Streams and reserved device names are never project files.
+    #[cfg(windows)]
+    mod windows_paths {
+        use super::*;
+        use std::sync::Arc;
+        use std::sync::atomic::{AtomicBool, Ordering};
+        use tokio::net::windows::named_pipe::ServerOptions;
+
+        /// Every spelling of the local pipe `name` that Windows opens: device, verbatim, object
+        /// manager and network (through the SMB redirector, as a remote host would be reached).
+        fn spellings(name: &str) -> [String; 6] {
+            [
+                format!(r"\\.\pipe\{name}"),
+                format!(r"//./pipe/{name}"),
+                format!(r"\\?\pipe\{name}"),
+                format!(r"\\?\GLOBALROOT\Device\NamedPipe\{name}"),
+                format!(r"\\127.0.0.1\pipe\{name}"),
+                format!(r"\\?\UNC\127.0.0.1\pipe\{name}"),
+            ]
+        }
+
+        /// Each resolver, as `(name, accepts root path)`.
+        type Resolver = (&'static str, fn(&Path, &str) -> bool);
+
+        const RESOLVERS: [Resolver; 11] = [
+            ("resolve_in_root", |root, path| resolve_in_root(root, path).is_ok()),
+            ("resolve_in_roots", |root, path| resolve_in_roots(&[root.to_path_buf()], path).is_ok()),
+            ("inside_root", |root, path| inside_root(root, path).unwrap_or(false)),
+            ("inside_roots", |root, path| inside_roots(&[root.to_path_buf()], path).unwrap_or(false)),
+            ("resolve_new_in_root", |root, path| resolve_new_in_root(root, path).is_ok()),
+            ("resolve_new_in_roots", |root, path| resolve_new_in_roots(&[root.to_path_buf()], path).is_ok()),
+            ("resolve_writable_in_root", |root, path| resolve_writable_in_root(root, path).is_ok()),
+            ("resolve_writable_in_roots", |root, path| resolve_writable_in_roots(&[root.to_path_buf()], path).is_ok()),
+            ("resolve_granted", |root, path| resolve_granted(&[grant_for(root)], path).is_ok()),
+            ("resolve_writable", |root, path| {
+                resolve_writable(&[Capability::FsWrite(strip_verbatim(&dunce::canonicalize(root).unwrap()))], path)
+                    .is_ok()
+            }),
+            ("project_of", |root, path| innermost_root(vec![root.to_path_buf()], Path::new(path)).is_some()),
+        ];
+
+        #[test]
+        fn pipe_and_network_paths_are_refused_without_being_opened() {
+            let tmp = tempfile::tempdir().unwrap();
+            let root = tmp.path().join("project");
+            std::fs::create_dir(&root).unwrap();
+            let runtime = tokio::runtime::Builder::new_current_thread().enable_all().build().unwrap();
+            let _context = runtime.enter();
+            let mut probes = Vec::new();
+            for (resolver, accepts) in RESOLVERS {
+                for spelling in 0..spellings("").len() {
+                    let name = format!("openidea-sandbox-{}-{resolver}-{spelling}", std::process::id());
+                    let server = ServerOptions::new().first_pipe_instance(true).create(format!(r"\\.\pipe\{name}"));
+                    let server = server.unwrap();
+                    let opened = Arc::new(AtomicBool::new(false));
+                    let flag = opened.clone();
+                    runtime.spawn(async move {
+                        let _ = server.connect().await;
+                        flag.store(true, Ordering::SeqCst);
+                    });
+                    let path = spellings(&name)[spelling].clone();
+                    let accepted = accepts(&root, &path);
+                    probes.push((resolver, path, accepted, opened));
+                }
+            }
+            runtime.block_on(tokio::time::sleep(std::time::Duration::from_millis(500)));
+            let failures: Vec<String> = probes
+                .iter()
+                .filter(|(_, _, accepted, opened)| *accepted || opened.load(Ordering::SeqCst))
+                .map(|(resolver, path, accepted, opened)| {
+                    format!("{resolver}({path}): accepted={accepted} opened={}", opened.load(Ordering::SeqCst))
+                })
+                .collect();
+            assert!(failures.is_empty(), "{failures:#?}");
+        }
+
+        #[test]
+        fn streams_and_device_names_are_refused() {
+            let tmp = tempfile::tempdir().unwrap();
+            let root = tmp.path().join("project");
+            std::fs::create_dir(&root).unwrap();
+            std::fs::write(root.join("a.txt"), "text").unwrap();
+            let root = dunce::canonicalize(root).unwrap();
+            let mut accepted = Vec::new();
+            for rel in ["a.txt:hidden", "a.txt::$DATA", "NUL", "con.txt", "sub/COM1", "LPT1.log", "CONIN$"] {
+                for path in [rel.to_owned(), root.join(rel).to_string_lossy().into_owned()] {
+                    for (resolver, accepts) in RESOLVERS {
+                        if accepts(&root, &path) {
+                            accepted.push(format!("{resolver}({path})"));
+                        }
+                    }
+                }
+            }
+            assert!(accepted.is_empty(), "{accepted:#?}");
+        }
+
+        #[test]
+        fn a_share_path_is_resolved_only_under_a_root_on_that_share() {
+            let root = Path::new(r"\\?\UNC\server\share\proj");
+            for path in
+                [r"\\server\share\proj\a.txt", r"\\SERVER\Share\Proj\src\..\a.txt", r"\\?\UNC\server\share\proj"]
+            {
+                assert_eq!(judge(Path::new(path), &[root]), Lexical::Resolvable, "{path}");
+            }
+            for path in [
+                r"\\server\other\a.txt",
+                r"\\elsewhere\share\proj\a.txt",
+                r"\\server\share\proj\..\..\other\a.txt",
+                r"\\server\share\project\a.txt",
+            ] {
+                assert_eq!(judge(Path::new(path), &[root]), Lexical::Outside, "{path}");
+                assert_eq!(judge(Path::new(path), &[Path::new(r"C:\proj")]), Lexical::Outside, "{path}");
+            }
+            for path in [r"C:\proj\a.txt", r"\\?\C:\elsewhere\a.txt", r"D:\x"] {
+                assert_eq!(judge(Path::new(path), &[root]), Lexical::Resolvable, "{path}");
+            }
+            assert_eq!(judge(Path::new(r"\\server\share\proj\a.txt:s"), &[root]), Lexical::Refused);
+            assert!(!names_device("console.log") && !names_device("com10") && !names_device("aux_utils.rs"));
+        }
+    }
 }

crates/ide-plugin/src/wit_host.rs

@@ -1770,6 +1770,12 @@ impl views::Host for StoreData {
             )
             .map_err(to_wit))
     }
+    fn open_diff(&mut self, diff: views::ContentDiff, file_name: Option<String>) -> Fallible<()> {
+        if let Err(e) = self.require_window() {
+            return Ok(Err(e));
+        }
+        Ok(self.host.open_diff(self.invocation.client.as_deref().unwrap(), diff.into(), file_name).map_err(to_wit))
+    }
     fn reply_content_tab(&mut self, request_id: String, reply: views::ContentTabReply) -> Fallible<()> {
         if let Err(e) = self.require_window() {
             return Ok(Err(e));

crates/ide-plugin/tests/api_compat.rs

@@ -91,15 +91,15 @@ fn the_sdk_carries_the_hosts_wit() {
 
 #[test]
 fn the_version_check_runs_compatible_components_and_explains_the_rest() {
-    let host = v("1.6.0");
-    for ok in ["1.0.0", "1.3.0", "1.4.7", "1.5.0", "1.6.0", "1.0.0-rc.1"] {
+    let host = v("1.7.0");
+    for ok in ["1.0.0", "1.3.0", "1.4.7", "1.5.0", "1.6.0", "1.7.0", "1.0.0-rc.1"] {
         assert_eq!(check_api(&v(ok), &host), Ok(()), "{ok}");
     }
-    let newer = check_api(&v("1.7.0"), &host).unwrap_err();
-    assert!(newer.contains("1.7") && newer.contains("update OpenIDEA"), "{newer}");
+    let newer = check_api(&v("1.8.0"), &host).unwrap_err();
+    assert!(newer.contains("1.8") && newer.contains("update OpenIDEA"), "{newer}");
     assert!(check_api(&v("2.0.0"), &host).unwrap_err().contains("update OpenIDEA"));
     let older = check_api(&v("0.2.0"), &host).unwrap_err();
-    assert!(older.contains("rebuild it with the 1.6 SDK"), "{older}");
+    assert!(older.contains("rebuild it with the 1.7 SDK"), "{older}");
     // 0.x: every minor is its own API.
     assert_eq!(check_api(&v("0.2.0"), &v("0.2.5")), Ok(()));
     assert!(check_api(&v("0.1.0"), &v("0.2.0")).is_err());

crates/ide-plugin/tests/fixtures/api14/dist/plugin.wasm.sources

@@ -1 +1 @@
-005d9da29eb7d713a97ff872051e408f653030434d837835843298553c9e12e0
+3c7f35facd15ee8380ccb6475b7c051d500e38346b711e1805077becd0c75f75

crates/ide-plugin/tests/fixtures/commit/dist/plugin.wasm.sources

@@ -1 +1 @@
-6359ef4271f38374889412bd926d9aa735f59a8ce047ffcb06c47976444196cf
+3879822d975695c6258e95286b0e64c5ee1e3265876501efaf0e577b38f8222b

crates/ide-plugin/tests/fixtures/data-tools/dist/plugin.wasm.sources

@@ -1 +1 @@
-6f560f3d0d7737150d2dfa09c3b801bd3b4c3a52cef9893ed8fc045809fe33e1
+228ae888bf556ce5cedc7843eb20e92f221d9e1f640f3c6c595bed3fd6be6051

crates/ide-plugin/tests/fixtures/detail-views/dist/plugin.wasm.sources

@@ -1 +1 @@
-4024af2d55d7fe4e8c456efd7e0c497ade4b2c5959e9108ff218f4a669e920f4
+41de239b6f723020b38eb2b67f642b7c88cc88c79117c3072ba122633afc418c