fix(client): surface background service startup errors

packages/ai/src/protocols/bedrock-converse.ts

@@ -348,7 +348,10 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (
           continue
         }
       }
-      messages.push({ role: "user", content })
+      const previous = messages.at(-1)
+      if (previous?.role === "user")
+        messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] }
+      else messages.push({ role: "user", content })
       continue
     }
 
@@ -392,7 +395,10 @@ const lowerMessages = Effect.fn("BedrockConverse.lowerMessages")(function* (
       const cachePoint = BedrockCache.block(breakpoints, part.cache)
       if (cachePoint) content.push(cachePoint)
     }
-    messages.push({ role: "user", content })
+    const previous = messages.at(-1)
+    if (previous?.role === "user")
+      messages[messages.length - 1] = { role: "user", content: [...previous.content, ...content] }
+    else messages.push({ role: "user", content })
   }
 
   return messages

packages/ai/test/fixtures/recordings/bedrock-converse/continues-after-parallel-tool-results.json

@@ -0,0 +1,36 @@
+{
+  "version": 1,
+  "metadata": {
+    "tags": [
+      "prefix:bedrock-converse",
+      "provider:amazon-bedrock",
+      "protocol:bedrock-converse",
+      "tool",
+      "tool-loop",
+      "parallel"
+    ],
+    "name": "bedrock-converse/continues-after-parallel-tool-results",
+    "recordedAt": "2026-08-11T16:41:46.482Z"
+  },
+  "interactions": [
+    {
+      "transport": "http",
+      "request": {
+        "method": "POST",
+        "url": "https://bedrock-runtime.us-east-1.amazonaws.com/model/us.amazon.nova-micro-v1%3A0/converse-stream",
+        "headers": {
+          "content-type": "application/json"
+        },
+        "body": "{\"modelId\":\"us.amazon.nova-micro-v1:0\",\"messages\":[{\"role\":\"user\",\"content\":[{\"text\":\"Compare the weather in Paris and London.\"}]},{\"role\":\"assistant\",\"content\":[{\"toolUse\":{\"toolUseId\":\"weather_paris\",\"name\":\"get_weather\",\"input\":{\"city\":\"Paris\"}}},{\"toolUse\":{\"toolUseId\":\"weather_london\",\"name\":\"get_weather\",\"input\":{\"city\":\"London\"}}}]},{\"role\":\"user\",\"content\":[{\"toolResult\":{\"toolUseId\":\"weather_paris\",\"content\":[{\"json\":{\"temperature\":22,\"condition\":\"sunny\"}}],\"status\":\"success\"}},{\"toolResult\":{\"toolUseId\":\"weather_london\",\"content\":[{\"json\":{\"temperature\":14,\"condition\":\"rainy\"}}],\"status\":\"success\"}}]}],\"system\":[{\"text\":\"After receiving both tool results, reply exactly: Paris is sunny; London is rainy.\"}],\"inferenceConfig\":{\"maxTokens\":40,\"temperature\":0},\"toolConfig\":{\"tools\":[{\"toolSpec\":{\"name\":\"get_weather\",\"description\":\"Get current weather for a city.\",\"inputSchema\":{\"json\":{\"type\":\"object\",\"properties\":{\"city\":{\"type\":\"string\"}},\"required\":[\"city\"],\"additionalProperties\":false}}}}]}}"
+      },
+      "response": {
+        "status": 200,
+        "headers": {
+          "content-type": "application/vnd.amazon.eventstream"
+        },
+        "body": "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",
+        "bodyEncoding": "base64"
+      }
+    }
+  ]
+}

packages/ai/test/provider/bedrock-converse.test.ts

@@ -255,6 +255,57 @@ describe("Bedrock Converse route", () => {
     }),
   )
 
+  it.effect("merges parallel tool results into one user message", () =>
+    Effect.gen(function* () {
+      const prepared = yield* compileRequest(
+        LLM.request({
+          id: "req_parallel_history",
+          model,
+          messages: [
+            Message.user("Compare the weather."),
+            Message.assistant([
+              ToolCallPart.make({ id: "tool_paris", name: "lookup", input: { city: "Paris" } }),
+              ToolCallPart.make({ id: "tool_london", name: "lookup", input: { city: "London" } }),
+            ]),
+            Message.tool({ id: "tool_paris", name: "lookup", result: { forecast: "sunny" } }),
+            Message.tool({ id: "tool_london", name: "lookup", result: { forecast: "rainy" } }),
+          ],
+          cache: "none",
+        }),
+      )
+
+      expect(prepared.body.messages).toEqual([
+        { role: "user", content: [{ text: "Compare the weather." }] },
+        {
+          role: "assistant",
+          content: [
+            { toolUse: { toolUseId: "tool_paris", name: "lookup", input: { city: "Paris" } } },
+            { toolUse: { toolUseId: "tool_london", name: "lookup", input: { city: "London" } } },
+          ],
+        },
+        {
+          role: "user",
+          content: [
+            {
+              toolResult: {
+                toolUseId: "tool_paris",
+                content: [{ json: { forecast: "sunny" } }],
+                status: "success",
+              },
+            },
+            {
+              toolResult: {
+                toolUseId: "tool_london",
+                content: [{ json: { forecast: "rainy" } }],
+                status: "success",
+              },
+            },
+          ],
+        },
+      ])
+    }),
+  )
+
   it.effect("lowers image content in tool-result messages", () =>
     Effect.gen(function* () {
       const prepared = yield* compileRequest(
@@ -1165,4 +1216,39 @@ describe("Bedrock Converse recorded", () => {
       )
     }),
   )
+
+  recorded.effect.with("continues after parallel tool results", { tags: ["tool", "tool-loop", "parallel"] }, () =>
+    Effect.gen(function* () {
+      const response = yield* LLMClient.generate(
+        LLM.request({
+          id: "recorded_bedrock_parallel_tool_results",
+          model: recordedModel(),
+          system: "After receiving both tool results, reply exactly: Paris is sunny; London is rainy.",
+          messages: [
+            Message.user("Compare the weather in Paris and London."),
+            Message.assistant([
+              ToolCallPart.make({ id: "weather_paris", name: weatherToolName, input: { city: "Paris" } }),
+              ToolCallPart.make({ id: "weather_london", name: weatherToolName, input: { city: "London" } }),
+            ]),
+            Message.tool({
+              id: "weather_paris",
+              name: weatherToolName,
+              result: { temperature: 22, condition: "sunny" },
+            }),
+            Message.tool({
+              id: "weather_london",
+              name: weatherToolName,
+              result: { temperature: 14, condition: "rainy" },
+            }),
+          ],
+          tools: [weatherTool],
+          cache: "none",
+          generation: { maxTokens: 40, temperature: 0 },
+        }),
+      )
+
+      expect(response.text.trim()).toBe("Paris is sunny; London is rainy.")
+      expect(response.finishReason?.normalized).toBe("stop")
+    }),
+  )
 })

packages/cli/src/server-process.ts

@@ -39,6 +39,8 @@ export const run = Effect.fnUntraced(function* (options: Options) {
 })
 
 const processEffect = Effect.fnUntraced(function* (options: Options) {
+  const serviceErrorFormat = process.env.OPENCODE_SERVICE_ERROR_FORMAT
+  delete process.env.OPENCODE_SERVICE_ERROR_FORMAT
   const global = yield* Global.Service
   if (options.mode === "service") yield* Effect.sync(() => process.chdir(global.home))
   return yield* Effect.scoped(
@@ -127,15 +129,7 @@ const processEffect = Effect.fnUntraced(function* (options: Options) {
           if (serviceOptions === undefined || port === undefined || !addressInUse(error)) return Effect.fail(error)
           return recognizeIncumbent(serviceOptions, hostname, port).pipe(
             Effect.flatMap((found) =>
-              found
-                ? Effect.void
-                : Effect.fail(
-                    new Error(
-                      `Managed service port ${port} on ${hostname} is already in use by another process. ` +
-                        "Configure another port with `opencode service set port <port>` and start the service again.",
-                      { cause: error },
-                    ),
-                  ),
+              found ? Effect.void : managedPortInUse(hostname, port, error, serviceErrorFormat),
             ),
           )
         }),
@@ -214,6 +208,17 @@ function serviceURL(hostname: string, port: number) {
   return `http://${hostname.includes(":") ? `[${hostname}]` : hostname}:${port}`
 }
 
+function managedPortInUse(hostname: string, port: number, cause: unknown, format?: string) {
+  const message =
+    `Managed service port ${port} on ${hostname} is already in use by another process. ` +
+    "Configure another port with `opencode service set port <port>` and start the service again."
+  const failure = new Error(message, { cause })
+  if (format !== "plain") return Effect.fail(failure)
+  return Effect.sync(() => process.stderr.write(`OPENCODE_SERVICE_ERROR:${message}\n`)).pipe(
+    Effect.andThen(Effect.fail(failure)),
+  )
+}
+
 function truthy(value?: string) {
   return value === "1" || value?.toLowerCase() === "true"
 }

packages/client/src/effect/service.ts

@@ -1,9 +1,9 @@
 import { ServiceStatus } from "@opencode-ai/protocol/groups/health"
 import { Effect, FileSystem, Option, Schedule, Schema } from "effect"
-import { spawn, type ChildProcess } from "node:child_process"
 import { homedir } from "node:os"
 import { join } from "node:path"
 import type { DiscoverOptions, Endpoint, EnsureOptions, StopOptions } from "../service.js"
+import { ServiceProcess } from "../service-process.js"
 
 export * from "../service.js"
 /** Contents of the local service registration file. */
@@ -17,11 +17,6 @@ export type Info = import("../service.js").Info
 // is all a client needs to connect. The daemon's own configuration (port,
 // persisted password) is CLI-owned and never read here.
 
-type Contender = {
-  readonly child: ChildProcess
-  readonly error: () => Error | undefined
-}
-
 // Read-only lookup: registration file plus health check and version gate.
 // Never spawns; escalation to ensure() is the caller's policy.
 /** Discover a healthy, compatible local service without starting one. */
@@ -52,11 +47,12 @@ const discoverLocal = Effect.fnUntraced(function* (options: DiscoverOptions) {
 // becomes discoverable. A contender is never killed merely for slow startup.
 /** Ensure a healthy, compatible local service is running. */
 export const ensure = Effect.fn("service.ensure")(function* (options: EnsureOptions = {}) {
-  const contenders = new Set<Contender>()
+  const contenders = new Set<ServiceProcess.Contender>()
   let timeouts: { readonly info: Info; readonly count: number } | undefined
   let announced = false
   let lastSpawn = 0
   let spawnDelay = 5_000
+  let lastFailure: Error | undefined
   const announce = (reason: "missing" | "version-mismatch", previousVersion?: string) =>
     Effect.sync(() => {
       if (announced) return
@@ -67,15 +63,7 @@ export const ensure = Effect.fn("service.ensure")(function* (options: EnsureOpti
     const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
     if (command === undefined) return yield* Effect.fail(new Error("Missing service command"))
     return yield* Effect.try({
-      try: () => {
-        const child = spawn(command, args, { detached: true, stdio: "ignore" })
-        let error: Error | undefined
-        child.once("error", (cause) => {
-          error = new Error("Failed to start server", { cause })
-        })
-        child.unref()
-        return { child, error: () => error }
-      },
+      try: () => ServiceProcess.start(command, args),
       catch: (cause) => new Error("Failed to start server", { cause }),
     })
   })
@@ -108,8 +96,9 @@ export const ensure = Effect.fn("service.ensure")(function* (options: EnsureOpti
       return Option.none<LocalService>()
     } else if (lastSpawn === 0 && info !== undefined) lastSpawn = Date.now()
 
-    const finished = [...contenders].filter(contenderFinished)
-    const failure = finished.map(contenderFailure).find((error): error is Error => error !== undefined)
+    const finished = [...contenders].filter(ServiceProcess.finished)
+    const failure = finished.map(ServiceProcess.failure).find((error): error is Error => error !== undefined)
+    if (failure !== undefined) lastFailure = failure
     if (finished.some((item) => item.child.exitCode === 0)) {
       spawnDelay = Math.min(spawnDelay * 2, 30_000)
     }
@@ -129,24 +118,10 @@ export const ensure = Effect.fn("service.ensure")(function* (options: EnsureOpti
     }),
   )
   if (Option.isNone(found))
-    return yield* Effect.fail(new Error("Timed out waiting for the background service to start"))
+    return yield* Effect.fail(lastFailure ?? new Error("Timed out waiting for the background service to start"))
   return found.value.endpoint
 })
 
-function contenderFailure(contender: Contender) {
-  const error = contender.error()
-  if (error !== undefined) return error
-  if (contender.child.exitCode !== null && contender.child.exitCode !== 0)
-    return new Error(`Server process exited with code ${contender.child.exitCode}`)
-  if (contender.child.signalCode !== null)
-    return new Error(`Server process terminated by ${contender.child.signalCode}`)
-  return undefined
-}
-
-function contenderFinished(contender: Contender) {
-  return contender.error() !== undefined || contender.child.exitCode !== null || contender.child.signalCode !== null
-}
-
 /** Stop the registered local service. */
 export const stop = Effect.fn("service.stop")(function* (options: StopOptions = {}) {
   const existing = yield* find(options)

packages/client/src/promise/service.ts

@@ -1,8 +1,8 @@
 import { readFile } from "node:fs/promises"
-import { spawn, type ChildProcess } from "node:child_process"
 import { homedir } from "node:os"
 import { join } from "node:path"
 import type { DiscoverOptions, Endpoint, Info, EnsureOptions, StopOptions } from "../service.js"
+import { ServiceProcess } from "../service-process.js"
 import type { ServiceHealth, ServiceStopResponse } from "./generated/types.js"
 
 export * from "../service.js"
@@ -13,11 +13,6 @@ export * from "../service.js"
 // intentionally implemented with Node APIs so Promise clients do not need
 // Effect or @effect/platform-node at runtime.
 
-type Contender = {
-  readonly child: ChildProcess
-  readonly error: () => Error | undefined
-}
-
 /** Discover a healthy, compatible local service without starting one. */
 export async function discover(options: DiscoverOptions = {}) {
   return (await discoverLocal(options))?.endpoint
@@ -33,11 +28,12 @@ async function discoverLocal(options: DiscoverOptions) {
 /** Ensure a healthy, compatible local service is running. */
 export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
   const deadline = Date.now() + 120_000
-  const contenders = new Set<Contender>()
+  const contenders = new Set<ServiceProcess.Contender>()
   let timeouts: { readonly info: Info; readonly count: number } | undefined
   let announced = false
   let lastSpawn = 0
   let spawnDelay = 5_000
+  let lastFailure: Error | undefined
 
   const announce = (reason: "missing" | "version-mismatch", previousVersion?: string) => {
     if (announced) return
@@ -47,21 +43,11 @@ export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
   const spawnContender = () => {
     const [command, ...args] = options.command ?? ["opencode", "serve", "--service"]
     if (command === undefined) throw new Error("Missing service command")
-    try {
-      const child = spawn(command, args, { detached: true, stdio: "ignore" })
-      let error: Error | undefined
-      child.once("error", (cause) => {
-        error = new Error("Failed to start server", { cause })
-      })
-      child.unref()
-      return { child, error: () => error }
-    } catch (cause) {
-      throw new Error("Failed to start server", { cause })
-    }
+    return ServiceProcess.start(command, args)
   }
 
   while (true) {
-    if (Date.now() >= deadline) throw new Error("Timed out waiting for the background service to start")
+    if (Date.now() >= deadline) throw lastFailure ?? new Error("Timed out waiting for the background service to start")
     const registration = await registered(options.file, true)
     if (registration.timedOut && registration.info !== undefined) {
       timeouts = {
@@ -89,8 +75,9 @@ export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
       }
     } else {
       if (lastSpawn === 0 && registration.info !== undefined) lastSpawn = Date.now()
-      const finished = [...contenders].filter(contenderFinished)
-      const failure = finished.map(contenderFailure).find((error) => error !== undefined)
+      const finished = [...contenders].filter(ServiceProcess.finished)
+      const failure = finished.map(ServiceProcess.failure).find((error) => error !== undefined)
+      if (failure !== undefined) lastFailure = failure
       if (finished.some((item) => item.child.exitCode === 0)) {
         spawnDelay = Math.min(spawnDelay * 2, 30_000)
       }
@@ -107,20 +94,6 @@ export async function ensure(options: EnsureOptions = {}): Promise<Endpoint> {
   }
 }
 
-function contenderFailure(contender: Contender) {
-  const error = contender.error()
-  if (error !== undefined) return error
-  if (contender.child.exitCode !== null && contender.child.exitCode !== 0)
-    return new Error(`Server process exited with code ${contender.child.exitCode}`)
-  if (contender.child.signalCode !== null)
-    return new Error(`Server process terminated by ${contender.child.signalCode}`)
-  return undefined
-}
-
-function contenderFinished(contender: Contender) {
-  return contender.error() !== undefined || contender.child.exitCode !== null || contender.child.signalCode !== null
-}
-
 /** Stop the registered local service. */
 export async function stop(options: StopOptions = {}) {
   const existing = await find(options)

packages/client/src/service-process.ts

@@ -0,0 +1,57 @@
+export * as ServiceProcess from "./service-process"
+
+import { spawn, type ChildProcess } from "node:child_process"
+
+const errorPrefix = "OPENCODE_SERVICE_ERROR:"
+
+export type Contender = {
+  readonly child: ChildProcess
+  readonly error: () => Error | undefined
+  readonly startupError: () => string
+}
+
+export function start(command: string, args: ReadonlyArray<string>) {
+  try {
+    const child = spawn(command, args, {
+      detached: true,
+      stdio: ["ignore", "ignore", "pipe"],
+      env: { ...process.env, OPENCODE_SERVICE_ERROR_FORMAT: "plain" },
+    })
+    let error: Error | undefined
+    let pending = ""
+    let startupError = ""
+    child.once("error", (cause) => {
+      error = new Error("Failed to start server", { cause })
+    })
+    child.stderr?.on("data", (chunk) => {
+      const lines = (pending + chunk.toString()).split(/\r?\n/)
+      pending = lines.pop()?.slice(-64 * 1024) ?? ""
+      const message = lines.findLast((line) => line.startsWith(errorPrefix))
+      if (message !== undefined) startupError = message.slice(errorPrefix.length)
+    })
+    unref(child.stderr)
+    child.unref()
+    return { child, error: () => error, startupError: () => startupError } satisfies Contender
+  } catch (cause) {
+    throw new Error("Failed to start server", { cause })
+  }
+}
+
+export function failure(contender: Contender) {
+  const error = contender.error()
+  if (error !== undefined) return error
+  if (contender.child.exitCode !== null && contender.child.exitCode !== 0)
+    return new Error(contender.startupError() || `Server process exited with code ${contender.child.exitCode}`)
+  if (contender.child.signalCode !== null)
+    return new Error(`Server process terminated by ${contender.child.signalCode}`)
+  return undefined
+}
+
+export function finished(contender: Contender) {
+  return contender.error() !== undefined || contender.child.exitCode !== null || contender.child.signalCode !== null
+}
+
+function unref(stream: ChildProcess["stderr"]) {
+  if (!stream || !("unref" in stream) || typeof stream.unref !== "function") return
+  stream.unref()
+}

packages/client/test/fixture/service.ts

@@ -3,6 +3,11 @@ import { appendFile, rename, writeFile } from "node:fs/promises"
 const [registration, mode, delay] = process.argv.slice(2)
 if (registration === undefined || mode === undefined) throw new Error("Missing service fixture arguments")
 if (mode === "failed") process.exit(1)
+if (mode === "failed-message") {
+  console.error("sensitive startup detail")
+  console.error("OPENCODE_SERVICE_ERROR:Managed service port is already in use")
+  process.exit(1)
+}
 if (mode === "record-start") {
   await writeFile(registration + ".started", "")
   process.exit(1)

packages/client/test/promise-service.test.ts

@@ -70,6 +70,19 @@ test("reports a failed registered service", async () => {
   )
 })
 
+test("reports the native contender's startup error", async () => {
+  const directory = await temp()
+  const registration = join(directory, "service.json")
+
+  await expect(
+    Service.ensure({
+      file: registration,
+      version: "test",
+      command: [process.execPath, fixture, registration, "failed-message"],
+    }),
+  ).rejects.toThrow(/^Managed service port is already in use$/)
+}, 10_000)
+
 test("evicts an unresponsive registered service before starting its replacement", async () => {
   const directory = await temp()
   const registration = join(directory, "service.json")

packages/client/test/service.test.ts

@@ -197,6 +197,20 @@ test("reports a contender that fails to start", async () => {
   ).rejects.toThrow("Server process exited with code 1")
 }, 10_000)
 
+test("reports the contender's startup error", async () => {
+  const directory = await temp()
+  const registration = join(directory, "service.json")
+  await expect(
+    run(
+      Service.ensure({
+        file: registration,
+        version: "test",
+        command: [process.execPath, fixture, registration, "failed-message"],
+      }),
+    ),
+  ).rejects.toThrow(/^Managed service port is already in use$/)
+}, 10_000)
+
 test("reports a contender terminated by a signal", async () => {
   const directory = await temp()
   const registration = join(directory, "service.json")

packages/core/src/session/runner/to-llm-message.ts

@@ -1,6 +1,5 @@
 import { Message, ToolCallPart, ToolResultPart, type ContentPart, type ProviderMetadata } from "@opencode-ai/ai"
 import { Option, Schema } from "effect"
-import { fileURLToPath } from "url"
 import type { Model } from "../../model"
 import { SessionMessage } from "../message"
 import type { FileAttachment } from "@opencode-ai/schema/prompt"
@@ -15,13 +14,6 @@ const media = (file: FileAttachment): ContentPart => ({
   metadata: file.description === undefined ? undefined : { description: file.description },
 })
 
-const attachmentLocation = (file: FileAttachment) => {
-  if (file.source.type !== "uri") return undefined
-  const url = URL.parse(file.source.uri)
-  if (url?.protocol !== "file:") return undefined
-  return fileURLToPath(url, { windows: url.hostname !== "" || /^\/[a-zA-Z]:\//.test(url.pathname) })
-}
-
 const textAttachment = (file: FileAttachment): ContentPart => ({
   type: "text",
   text: `\n\n${[
@@ -44,7 +36,7 @@ const textAttachment = (file: FileAttachment): ContentPart => ({
 const directoryAttachment = (file: FileAttachment): ContentPart => ({
   type: "text",
   text: `\n\n${[
-    `Attached directory: ${attachmentLocation(file) ?? file.name ?? (file.source.type === "uri" ? file.source.uri : "directory")}`,
+    `Attached directory: ${file.name ?? (file.source.type === "uri" ? file.source.uri : "directory")}`,
     file.description === undefined ? undefined : `Description: ${file.description}`,
     file.data.length === 0 ? undefined : "",
     file.data.length === 0 ? undefined : Buffer.from(file.data, "base64").toString("utf8"),
@@ -63,10 +55,7 @@ const directoryAttachment = (file: FileAttachment): ContentPart => ({
 const attachmentContent = (file: FileAttachment): ContentPart[] => {
   if (file.mime === "text/plain") return [textAttachment(file)]
   if (file.mime === "application/x-directory") return [directoryAttachment(file)]
-  if (imageMimes.has(file.mime)) {
-    const location = attachmentLocation(file)
-    return [...(location === undefined ? [] : [Message.text(`Attached file: ${location}`)]), media(file)]
-  }
+  if (imageMimes.has(file.mime)) return [media(file)]
   return []
 }
 

packages/core/src/tool/plugin/question.ts

@@ -21,9 +21,7 @@ Usage notes:
 - If you recommend a specific option, make that the first option in the list and add "(Recommended)" at the end of the label`
 
 export const Input = Schema.Struct({
-  questions: Schema.Array(Question.Prompt)
-    .check(Schema.isNonEmpty())
-    .annotate({ description: "Questions to ask" }),
+  questions: Schema.Array(Question.Prompt).check(Schema.isNonEmpty()).annotate({ description: "Questions to ask" }),
 })
 
 export const Output = Schema.Struct({

packages/core/test/session-runner-message.test.ts

@@ -249,14 +249,13 @@ Recent work
     ])
   })
 
-  test("exposes admitted reference directory source paths in model context", () => {
+  test("lowers directory attachments as directory context", () => {
     const directory = FileAttachment.make({
       data: Base64.make(Buffer.from("lib/\nindex.ts").toString("base64")),
       mime: "application/x-directory",
-      source: { type: "uri", uri: "file:///references/harness-engineering" },
-      name: "harness-engineering",
+      source: { type: "uri", uri: "file:///project/src" },
+      name: "src/",
     })
-    expect(directory.source).toEqual({ type: "uri", uri: "file:///references/harness-engineering" })
     const messages = toLLMMessages(
       [
         SessionMessage.User.make({
@@ -278,8 +277,8 @@ Recent work
         { type: "text", text: "Review this directory" },
         {
           type: "text",
-          text: "\n\nAttached directory: /references/harness-engineering\n\nlib/\nindex.ts",
-          metadata: { attachment: { source: directory.source, name: "harness-engineering" } },
+          text: "\n\nAttached directory: src/\n\nlib/\nindex.ts",
+          metadata: { attachment: { source: directory.source, name: "src/" } },
         },
       ],
     })
@@ -315,7 +314,7 @@ Recent work
     expect(messages).toHaveLength(1)
     expect(messages[0]?.content.map((part) => (part.type === "text" ? part.text : part.type))).toEqual([
       "Review these attachments",
-      "\n\nAttached directory: /project/src\n\nindex.ts",
+      "\n\nAttached directory: src/\n\nindex.ts",
       "\n\nAttached file: main.ts\n\nexport const value = 1",
     ])
   })
@@ -342,9 +341,7 @@ Recent work
     )
 
     expect(messages).toHaveLength(1)
-    expect(messages[0]?.content).toMatchObject([
-      { type: "text", text: "\n\nAttached directory: /project/src\n\nindex.ts" },
-    ])
+    expect(messages[0]?.content).toMatchObject([{ type: "text", text: "\n\nAttached directory: src/\n\nindex.ts" }])
   })
 
   test("uses materialized image data as provider media and drops unsupported attachments", () => {
@@ -376,64 +373,6 @@ Recent work
     ])
   })
 
-  test("exposes admitted local image source paths before provider media", () => {
-    const data = Base64.make("AAECAw==")
-    const image = FileAttachment.make({
-      data,
-      mime: "image/png",
-      source: { type: "uri", uri: "file:///project/IMG_3480.JPG" },
-      name: "IMG_3480.JPG",
-    })
-    expect(image.source).toEqual({ type: "uri", uri: "file:///project/IMG_3480.JPG" })
-
-    const messages = toLLMMessages(
-      [
-        SessionMessage.User.make({
-          id: id("user-local-image-path"),
-          type: "user",
-          text: "Inspect this image",
-          files: [image],
-          time: { created },
-        }),
-      ],
-      model,
-    )
-
-    expect(messages[0]?.content).toEqual([
-      { type: "text", text: "Inspect this image" },
-      { type: "text", text: "Attached file: /project/IMG_3480.JPG" },
-      { type: "media", mediaType: "image/png", data, filename: "IMG_3480.JPG" },
-    ])
-  })
-
-  test("does not add attachment location text for non-local provider media", () => {
-    const data = Base64.make("AAECAw==")
-    const messages = toLLMMessages(
-      [
-        SessionMessage.User.make({
-          id: id("user-remote-image"),
-          type: "user",
-          text: "Inspect this image",
-          files: [
-            FileAttachment.make({
-              data,
-              mime: "image/png",
-              source: { type: "uri", uri: "https://example.com/image.png" },
-              name: "image.png",
-            }),
-          ],
-          time: { created },
-        }),
-      ],
-      model,
-    )
-
-    expect(messages[0]?.content).toEqual([
-      { type: "text", text: "Inspect this image" },
-      { type: "media", mediaType: "image/png", data, filename: "image.png" },
-    ])
-  })
-
   test("deduplicates provider media while preserving durable attachment references", () => {
     const data = Base64.make("AAECAw==")
     const messages = toLLMMessages(

packages/server/src/handlers/model.ts

@@ -12,6 +12,19 @@ export const ModelHandler = HttpApiBuilder.group(Api, "server.model", (handlers)
       .handle(
         "model.list",
         Effect.fn(function* () {
+          const plugins = yield* PluginSupervisor.Service
+          yield* plugins.flush.pipe(
+            Effect.timeoutOrElse({
+              duration: "5 seconds",
+              orElse: () =>
+                Effect.fail(
+                  new ServiceUnavailableError({
+                    message: "Model catalog initialization timed out",
+                    service: "model.catalog",
+                  }),
+                ),
+            }),
+          )
           const catalog = yield* Catalog.Service
           return yield* response(catalog.model.available())
         }),

packages/server/test/model.test.ts

@@ -0,0 +1,57 @@
+import fs from "node:fs/promises"
+import path from "node:path"
+import { expect } from "bun:test"
+import { Effect } from "effect"
+import { HttpServer } from "effect/unstable/http"
+import { tmpdir } from "../../core/test/fixture/tmpdir"
+import { it } from "../../core/test/lib/effect"
+import { ServerProcess } from "../src/process"
+
+it.live("waits for plugin initialization before listing models", () =>
+  Effect.acquireUseRelease(
+    Effect.promise(() => tmpdir("opencode-model-endpoint-")),
+    (tmp) =>
+      Effect.gen(function* () {
+        yield* Effect.promise(() =>
+          fs.writeFile(
+            path.join(tmp.path, "opencode.json"),
+            JSON.stringify({
+              providers: {
+                custom: {
+                  package: "aisdk:@ai-sdk/openai-compatible",
+                  settings: { apiKey: "secret" },
+                  models: { chat: {} },
+                },
+              },
+            }),
+          ),
+        )
+        const server = yield* ServerProcess.start<never, never>({
+          hostname: "127.0.0.1",
+          port: 0,
+          password: "secret",
+          app: { version: "test-version" },
+          database: { path: ":memory:" },
+          config: { directory: tmp.path },
+          fs: { filewatcher: false },
+        })
+        const url = new URL("/api/model", HttpServer.formatAddress(server.address))
+        url.searchParams.set("location[directory]", tmp.path)
+        const response = yield* Effect.promise(() =>
+          fetch(url, { headers: { authorization: `Basic ${btoa("opencode:secret")}` } }),
+        )
+
+        expect(response.status).toBe(200)
+        const body: unknown = yield* Effect.promise(() => response.json())
+        if (!isRecord(body) || !Array.isArray(body["data"])) throw new Error("Expected a model list response")
+        expect(
+          body["data"].some((model) => isRecord(model) && model["providerID"] === "custom" && model["id"] === "chat"),
+        ).toBeTrue()
+      }),
+    (tmp) => Effect.promise(() => tmp[Symbol.asyncDispose]()),
+  ),
+)
+
+function isRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value)
+}