fix(providerio): disable HTTP keep-alive reuse on macOS to defeat degraded-connection stalls

This codebase already has a documented, previously-diagnosed macOS-only
bug: "sharedHTTPClient... defeats the stale-pooled-connection hang...
reproduced on BOTH chatgpt and ollama... surfaces on macOS far more than
Linux because macOS keeps dead pooled connections around longer." The
existing mitigation (ResponseHeaderTimeout=120s, IdleConnTimeout=30s)
catches a reused connection that never responds at all, or one that sat
idle too long.

Traced a live report that doesn't fit either case: a session accumulated
301 real completion tokens over ~12.5 minutes (~0.4 tok/s) on
chatgpt/gpt-5.5 before being manually cancelled - not silent, just
catastrophically slow, on a retry shortly after a prior attempt on the
same host. That's a third failure mode: a reused connection that's
alive-but-severely-degraded, still delivering real bytes (enough to keep
resetting Zero's stream idle/content-stall watchdogs, which only fire on
true silence) but never at a usable rate. Basic network diagnostics on
the affected machine (DNS, TCP connect, TLS handshake) were all healthy
and routed directly with no VPN/proxy involved, pointing at the same
connection-reuse class of bug rather than a local network misconfig.

DisableKeepAlives removes pooling from the equation entirely rather than
just tightening the timeout window, since a degraded-not-dead connection
isn't reliably distinguishable from genuine backend slowness once inside
the stream. Scoped to darwin only via runtime.GOOS: a fresh TCP+TLS
handshake per request costs low tens of milliseconds (measured ~92ms
against a real host on the affected machine) against potential
minutes-long stalls, and Linux/Windows don't exhibit this OS-level
pooled-connection behavior, so they keep full connection reuse.

New test: TestHTTPClientReturnsStallHardenedSharedClient extended to
assert DisableKeepAlives matches runtime.GOOS == "darwin".

CHANGELOG.md

@@ -11,7 +11,14 @@ tagged. Until then, source builds report the version `dev`.
 ### Added
 - `SECURITY.md` with a private vulnerability-reporting path, `CODE_OF_CONDUCT.md`, this changelog, and
   GitHub issue/PR templates.
-- `--theme {auto|dark|light}` flag for the TUI (previously only the `ZERO_THEME` env var existed).
+- Interactive `/theme` picker: bare `/theme` opens a popup that live-previews each palette as you move
+  and applies on select (Esc reverts).
+- Ten built-in color themes alongside the `dark`/`light` built-ins — `dracula`, `nord`, `gruvbox`,
+  `tokyo-night`, `catppuccin`, `one-dark`, `solarized-dark`, `rose-pine`, `everforest`, and
+  `solarized-light` — selectable via `/theme <name>`, `--theme <name>`, or `ZERO_THEME`. Every palette
+  is contrast-audited to WCAG AA. The built-in light theme was reworked for legibility.
+- `--theme <name>` flag for the TUI, accepting `auto` or any registered theme (previously only the
+  `ZERO_THEME` env var existed).
 - "Accessibility / Appearance" section in the README documenting `NO_COLOR`, `ZERO_THEME`, `/theme`,
   and `ZERO_NO_FADE`.
 

README.md

@@ -254,9 +254,9 @@ zero update           check for newer releases
 | Control | Effect |
 |---|---|
 | `NO_COLOR=<anything>` | disables color output |
-| `ZERO_THEME=auto|dark|light` | selects the startup theme |
-| `--theme auto|dark|light` | selects the TUI theme from the CLI |
-| `/theme auto|dark|light` | switches theme inside the TUI |
+| `ZERO_THEME=<name>` | selects the startup theme (`auto`, `dark`, `light`, or a color theme like `dracula`, `nord`, `gruvbox`, `tokyo-night`, `catppuccin`, `one-dark`, `solarized-dark`, `rose-pine`, `everforest`, `solarized-light`) |
+| `--theme <name>` | selects the TUI theme from the CLI (same names) |
+| `/theme` | opens the theme picker inside the TUI (live preview; `/theme <name>` switches directly) |
 | `ZERO_NO_FADE=1` | disables streaming fade animation |
 
 Meaning does not rely on color alone; diffs, permissions, and statuses also use

internal/agenteval/benchmark_test.go

@@ -455,11 +455,15 @@ func TestHarnessTimeoutCancelsBlockedAgent(t *testing.T) {
 
 	// The timeout is longer than materialization of the small fixture even on
 	// slower Windows CI runners, so the agent is reached before it blocks until
-	// the deadline fires.
+	// the deadline fires. 10s wasn't generous enough in practice — it failed
+	// on an otherwise-unrelated PR merge (materialization alone consumed the
+	// full budget on a contended Windows runner, so the agent was never
+	// reached); widened for headroom, since the assertions below still bound
+	// worst-case test time via that same deadline, not this constant.
 	report := harness.Run(context.Background(), suitePath, suite, BenchmarkInput{
 		TaskID:   "document-stream-json-verify-events",
 		WorkRoot: t.TempDir(),
-		Timeout:  10 * time.Second,
+		Timeout:  30 * time.Second,
 	})
 
 	if !agentReached {

internal/cli/app.go

@@ -217,9 +217,9 @@ func runWithDeps(args []string, stdout io.Writer, stderr io.Writer, deps appDeps
 	if err != nil {
 		return writeAppError(stderr, err.Error(), 1)
 	}
-	// --theme {auto|dark|light} selects the TUI palette non-interactively (populates
-	// tui.Options.Theme, which resolveThemeMode prefers over ZERO_THEME). Re-split
-	// --add-dir afterward so it may appear on either side of --theme.
+	// --theme <name> selects the TUI palette non-interactively (auto or any registered
+	// theme; populates tui.Options.Theme, which resolveThemeMode prefers over
+	// ZERO_THEME). Re-split --add-dir afterward so it may appear on either side of --theme.
 	theme, args, err := splitLeadingThemeFlag(args)
 	if err != nil {
 		return writeAppError(stderr, err.Error(), 1)
@@ -641,6 +641,7 @@ func runInteractiveTUIWithSetup(stderr io.Writer, deps appDeps, permissionMode a
 	return deps.runTUI(context.Background(), tui.Options{
 		Cwd:                  workspaceRoot,
 		Theme:                theme,
+		SavedTheme:           resolved.Preferences.Theme,
 		UserConfigPath:       userConfigPath,
 		DoctorUserConfigPath: doctorUserConfigPath,
 		ProjectConfigPath:    projectConfigPath,
@@ -1033,9 +1034,10 @@ func splitLeadingAddDirFlags(args []string) ([]string, []string, error) {
 	return addDirs, args, nil
 }
 
-// splitLeadingThemeFlag strips a leading --theme {auto|dark|light} (space or =form)
-// from the root argument list and validates it. The last occurrence wins. A value
-// outside the allowed set is a loud error rather than a silent fallback.
+// splitLeadingThemeFlag strips a leading --theme <auto|theme-name> (space or =form)
+// from the root argument list and validates it against the registered themes. The
+// last occurrence wins. A value outside the allowed set is a loud error rather than
+// a silent fallback.
 func splitLeadingThemeFlag(args []string) (string, []string, error) {
 	theme := ""
 	for len(args) > 0 {
@@ -1043,7 +1045,7 @@ func splitLeadingThemeFlag(args []string) (string, []string, error) {
 		switch {
 		case args[0] == "--theme":
 			if len(args) < 2 {
-				return "", nil, errors.New("--theme requires a value (auto, dark, or light)")
+				return "", nil, errors.New("--theme requires a value (auto or a theme name; try --theme auto)")
 			}
 			value = strings.TrimSpace(args[1])
 			args = args[2:]
@@ -1053,12 +1055,10 @@ func splitLeadingThemeFlag(args []string) (string, []string, error) {
 		default:
 			return theme, args, nil
 		}
-		switch strings.ToLower(value) {
-		case "auto", "dark", "light":
-			theme = strings.ToLower(value)
-		default:
-			return "", nil, fmt.Errorf("--theme must be auto, dark, or light (got %q)", value)
+		if !tui.ValidThemeArg(value) {
+			return "", nil, fmt.Errorf("--theme must be auto or a registered theme name (got %q)", value)
 		}
+		theme = strings.ToLower(value)
 	}
 	return theme, args, nil
 }

internal/cli/app_test.go

@@ -1397,7 +1397,7 @@ func TestRunThemeFlagRejectsBadValue(t *testing.T) {
 	if launched {
 		t.Fatal("the TUI must not launch on a bad --theme value")
 	}
-	if !strings.Contains(stderr.String(), "--theme must be auto, dark, or light") {
+	if !strings.Contains(stderr.String(), "--theme must be auto or a registered theme name") {
 		t.Fatalf("expected a clear --theme error, got %q", stderr.String())
 	}
 }

internal/cli/auth.go

@@ -283,6 +283,9 @@ func newAuthManager(deps appDeps, out io.Writer) (*oauth.Manager, error) {
 		// carries no token material. A real browser launch is intentionally not
 		// performed (the sandbox/headless contexts make printing the safer default).
 		OpenBrowser: func(string) error { return nil },
+		// `zero auth login <preset>` (e.g. xai) should resolve the baked-in preset
+		// without the operator exporting ZERO_OAUTH_ALLOW_PRESETS first.
+		AllowPresets: true,
 	})
 }
 

internal/cli/oauth_provider.go

@@ -43,6 +43,9 @@ func oauthResolverForProfile(profile config.ProviderProfile) providerio.TokenRes
 	manager, err := oauth.NewManager(oauth.ManagerOptions{
 		Store:      store,
 		HTTPClient: &http.Client{Timeout: 30 * time.Second},
+		// Refreshing a token the user logged into (possibly a preset provider like
+		// xAI) re-resolves that provider's OAuth config, which needs the preset.
+		AllowPresets: true,
 	})
 	if err != nil {
 		return nil

internal/config/resolver.go

@@ -195,6 +195,9 @@ func mergeConfig(dst *FileConfig, src FileConfig) {
 	if src.Preferences.Recaps != nil {
 		dst.Preferences.Recaps = src.Preferences.Recaps
 	}
+	if strings.TrimSpace(src.Preferences.Theme) != "" {
+		dst.Preferences.Theme = strings.TrimSpace(src.Preferences.Theme)
+	}
 	mergeLocalControlConfig(&dst.LocalControl, src.LocalControl)
 }
 

internal/config/types.go

@@ -97,6 +97,10 @@ type ToolsConfig struct {
 
 type PreferencesConfig struct {
 	FavoriteModels []string `json:"favoriteModels,omitempty"`
+	// Theme is the persisted TUI palette preference — "auto" or a registered theme
+	// name (e.g. "dracula"). Applied at startup below the --theme flag and
+	// ZERO_THEME, so a /theme choice survives restart. Empty = unset (defaults auto).
+	Theme string `json:"theme,omitempty"`
 	// Recaps is a tri-state: nil (unset) defaults to ON; an explicit false means
 	// the user turned post-turn recaps off. A *bool is its own tri-state, so no
 	// custom unmarshal is needed (unlike ToolsConfig.DeferThreshold's int).

internal/config/writer.go

@@ -154,6 +154,28 @@ func SetRecapsEnabled(path string, enabled bool) (FileConfig, error) {
 	return cfg, nil
 }
 
+// SetTheme persists the TUI theme preference, mirroring SetFavoriteModels
+// (read-modify-atomic-write). A blank theme clears the stored preference.
+func SetTheme(path string, theme string) (FileConfig, error) {
+	path = strings.TrimSpace(path)
+	if path == "" {
+		return FileConfig{}, fmt.Errorf("config path is required")
+	}
+	cfg := FileConfig{}
+	if data, err := os.ReadFile(path); err == nil {
+		if err := json.Unmarshal(data, &cfg); err != nil {
+			return FileConfig{}, fmt.Errorf("invalid config JSON %s: %w", path, err)
+		}
+	} else if !os.IsNotExist(err) {
+		return FileConfig{}, fmt.Errorf("read config %s: %w", path, err)
+	}
+	cfg.Preferences.Theme = strings.TrimSpace(theme)
+	if err := writeConfigFile(path, cfg); err != nil {
+		return FileConfig{}, err
+	}
+	return cfg, nil
+}
+
 func normalizeFavoriteModels(models []string) []string {
 	seen := map[string]bool{}
 	favorites := make([]string, 0, len(models))

internal/config/writer_test.go

@@ -272,6 +272,39 @@ func TestSetFavoriteModelsPersistsUserPreferences(t *testing.T) {
 	}
 }
 
+func TestSetThemePersistsUserPreference(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "zero.json")
+	writeConfigFixture(t, path, FileConfig{
+		ActiveProvider: "openai",
+		Providers: []ProviderProfile{
+			{Name: "openai", ProviderKind: ProviderKindOpenAI, Model: "gpt-4.1"},
+		},
+	}, 0o600)
+
+	cfg, err := SetTheme(path, "  dracula  ")
+	if err != nil {
+		t.Fatalf("SetTheme() error = %v", err)
+	}
+	if cfg.Preferences.Theme != "dracula" {
+		t.Fatalf("Theme = %q, want dracula (trimmed)", cfg.Preferences.Theme)
+	}
+	persisted := readConfigFixture(t, path)
+	if persisted.Preferences.Theme != "dracula" {
+		t.Fatalf("persisted Theme = %q, want dracula", persisted.Preferences.Theme)
+	}
+	if persisted.ActiveProvider != "openai" || len(persisted.Providers) != 1 {
+		t.Fatalf("provider config was not preserved by SetTheme: %#v", persisted)
+	}
+
+	// A blank value clears the stored preference.
+	if cfg, err = SetTheme(path, ""); err != nil {
+		t.Fatalf("SetTheme(\"\") error = %v", err)
+	}
+	if cfg.Preferences.Theme != "" {
+		t.Fatalf("SetTheme(\"\") should clear the theme, got %q", cfg.Preferences.Theme)
+	}
+}
+
 func TestRecapsPreferenceRoundTrips(t *testing.T) {
 	// Default (unset) is ON.
 	if !(PreferencesConfig{}).RecapsEnabled() {

internal/oauth/manager.go

@@ -44,10 +44,17 @@ type Manager struct {
 
 // ManagerOptions configures a Manager.
 type ManagerOptions struct {
-	Store         *Store
-	Registry      *Registry
-	HTTPClient    *http.Client
-	Env           map[string]string
+	Store      *Store
+	Registry   *Registry
+	HTTPClient *http.Client
+	Env        map[string]string
+	// AllowPresets opts this manager into the baked-in OAuth presets without the
+	// operator exporting ZERO_OAUTH_ALLOW_PRESETS — used by the interactive wizard
+	// and CLI login (and the runtime token refresh) for a provider the user chose
+	// to sign into, whose preset client identity is public (e.g. xAI). It layers the
+	// flag onto Env (or the process environment when Env is nil), preserving any
+	// ZERO_OAUTH_<NAME>_* overrides. Leave false for hermetic tests.
+	AllowPresets  bool
 	Now           func() time.Time
 	RefreshBuffer time.Duration
 	Out           io.Writer
@@ -83,9 +90,13 @@ func NewManager(opts ManagerOptions) (*Manager, error) {
 	if open == nil {
 		open = func(string) error { return nil }
 	}
+	env := opts.Env
+	if opts.AllowPresets {
+		env = envWithPresetsAllowed(env)
+	}
 	return &Manager{
 		store: opts.Store, registry: registry, client: client,
-		env: opts.Env, now: now, buffer: buffer, out: out, openBrowser: open,
+		env: env, now: now, buffer: buffer, out: out, openBrowser: open,
 	}, nil
 }
 

internal/oauth/manager_test.go

@@ -52,6 +52,30 @@ func managerFor(t *testing.T, env map[string]string, openBrowser func(string) er
 	return m
 }
 
+// AllowPresets layers the opt-in onto the manager's env so a login/refresh for a
+// preset provider resolves; without it (and no Env) the env stays nil so callers
+// and tests remain hermetic.
+func TestNewManagerAllowPresetsForcesOptIn(t *testing.T) {
+	store, err := NewStore(StoreOptions{FilePath: filepath.Join(t.TempDir(), "tok.json")})
+	if err != nil {
+		t.Fatalf("NewStore: %v", err)
+	}
+	m, err := NewManager(ManagerOptions{Store: store, AllowPresets: true})
+	if err != nil {
+		t.Fatalf("NewManager: %v", err)
+	}
+	if m.env["ZERO_OAUTH_ALLOW_PRESETS"] != "1" {
+		t.Fatalf("AllowPresets should force the opt-in; got env[%q]=%q", "ZERO_OAUTH_ALLOW_PRESETS", m.env["ZERO_OAUTH_ALLOW_PRESETS"])
+	}
+	m2, err := NewManager(ManagerOptions{Store: store})
+	if err != nil {
+		t.Fatalf("NewManager: %v", err)
+	}
+	if m2.env != nil {
+		t.Fatalf("env should stay nil without AllowPresets, got %v", m2.env)
+	}
+}
+
 func TestManagerLoginLoopback(t *testing.T) {
 	fp := newFakeProvider(t, `{"access_token":"at","refresh_token":"rt","token_type":"Bearer","expires_in":3600}`)
 	env := map[string]string{

internal/oauth/presets.go

@@ -1,6 +1,33 @@
 package oauth
 
-import "strings"
+import (
+	"os"
+	"strings"
+)
+
+// envWithPresetsAllowed returns an env map that opts into the baked-in presets
+// (as if ZERO_OAUTH_ALLOW_PRESETS=1 were exported) so an interactive wizard/CLI
+// login for a well-known public client (e.g. xAI) can use the preset without the
+// operator setting the flag themselves. It copies base — or snapshots the process
+// environment when base is nil — because envValue treats a non-nil map as hermetic
+// (a missing key does NOT fall back to os.Getenv), so a partial map would silently
+// drop the operator's ZERO_OAUTH_<NAME>_* overrides. The flag is then forced on.
+func envWithPresetsAllowed(base map[string]string) map[string]string {
+	env := make(map[string]string, len(base)+1)
+	if base == nil {
+		for _, kv := range os.Environ() {
+			if eq := strings.IndexByte(kv, '='); eq > 0 {
+				env[kv[:eq]] = kv[eq+1:]
+			}
+		}
+	} else {
+		for k, v := range base {
+			env[k] = v
+		}
+	}
+	env["ZERO_OAUTH_ALLOW_PRESETS"] = "1"
+	return env
+}
 
 // providerPreset is a baked-in default OAuth configuration for a well-known
 // provider. Every field is overridable per provider via ZERO_OAUTH_<NAME>_*

internal/oauth/presets_test.go

@@ -46,6 +46,46 @@ func TestResolveConfigUsesXAIPreset(t *testing.T) {
 	}
 }
 
+// envWithPresetsAllowed lets a caller (the wizard / CLI login / runtime refresh)
+// opt into the preset without exporting ZERO_OAUTH_ALLOW_PRESETS: an otherwise-inert
+// xAI config now resolves from the baked-in preset.
+func TestEnvWithPresetsAllowedEnablesPreset(t *testing.T) {
+	r := NewRegistry()
+	// Baseline: a hermetic empty map keeps the preset inert.
+	if _, _, err := r.ResolveConfig("xai", map[string]string{}); err == nil {
+		t.Fatal("xai should not resolve without the opt-in")
+	}
+	// The helper forces the opt-in so the preset resolves.
+	cfg, _, err := r.ResolveConfig("xai", envWithPresetsAllowed(map[string]string{}))
+	if err != nil {
+		t.Fatalf("envWithPresetsAllowed should enable the xai preset: %v", err)
+	}
+	if cfg.ClientID != "b1a00492-073a-47ea-816f-4c329264a828" {
+		t.Fatalf("client_id = %q", cfg.ClientID)
+	}
+}
+
+// The helper copies the base map (never mutating it) and keeps ZERO_OAUTH_<NAME>_*
+// overrides — critical because envValue treats a non-nil map as hermetic, so a
+// partial map would silently drop them.
+func TestEnvWithPresetsAllowedPreservesOverrides(t *testing.T) {
+	base := map[string]string{"ZERO_OAUTH_XAI_CLIENT_ID": "custom-id"}
+	env := envWithPresetsAllowed(base)
+	if env["ZERO_OAUTH_ALLOW_PRESETS"] != "1" {
+		t.Fatalf("opt-in flag not set: %v", env)
+	}
+	if _, mutated := base["ZERO_OAUTH_ALLOW_PRESETS"]; mutated {
+		t.Fatal("envWithPresetsAllowed mutated the caller's base map")
+	}
+	cfg, _, err := NewRegistry().ResolveConfig("xai", env)
+	if err != nil {
+		t.Fatalf("ResolveConfig with override env: %v", err)
+	}
+	if cfg.ClientID != "custom-id" {
+		t.Fatalf("override dropped through the helper: client_id = %q", cfg.ClientID)
+	}
+}
+
 func TestResolveConfigEnvOverridesPreset(t *testing.T) {
 	r := NewRegistry()
 	env := map[string]string{

internal/providermodeldiscovery/discovery.go

@@ -85,6 +85,104 @@ func Discover(ctx context.Context, profile config.ProviderProfile, options Optio
 	}
 }
 
+// DiscoverOllamaContextWindow asks a local Ollama daemon for a model's context
+// length via its native /api/show endpoint. The generic /v1/models probe
+// (parseModelsResponse) only ever returns id/description — OpenAI-compatible
+// listings don't carry context-window metadata, and a custom/local model tag
+// (e.g. a user's own Ollama pull, including a ":cloud"-tagged model proxied
+// through the local daemon) has no curated-catalog entry to borrow one from
+// either, so modelContextWindow has nothing to show for it without this. Only
+// meaningful for the local Ollama provider (baseURL like
+// http://localhost:11434/v1) — Ollama Cloud's hosted API is a different
+// service and isn't assumed to expose the same endpoint.
+func DiscoverOllamaContextWindow(ctx context.Context, baseURL string, model string, options Options) (int, error) {
+	model = strings.TrimSpace(model)
+	if model == "" {
+		return 0, fmt.Errorf("model name is required")
+	}
+	endpoint, err := ollamaShowEndpoint(baseURL)
+	if err != nil {
+		return 0, err
+	}
+	payload, err := json.Marshal(struct {
+		Model string `json:"model"`
+	}{Model: model})
+	if err != nil {
+		return 0, err
+	}
+	request, err := http.NewRequestWithContext(ctx, http.MethodPost, endpoint, strings.NewReader(string(payload)))
+	if err != nil {
+		return 0, err
+	}
+	request.Header.Set("Content-Type", "application/json")
+	request.Header.Set("Accept", "application/json")
+
+	client := options.HTTPClient
+	if client == nil {
+		client = &http.Client{Timeout: 10 * time.Second}
+	}
+	response, err := client.Do(request)
+	if err != nil {
+		return 0, err
+	}
+	defer response.Body.Close()
+
+	body, err := io.ReadAll(io.LimitReader(response.Body, 1<<20))
+	if err != nil {
+		return 0, err
+	}
+	if response.StatusCode < 200 || response.StatusCode >= 300 {
+		return 0, fmt.Errorf("ollama show endpoint returned %s: %s", response.Status, strings.TrimSpace(string(body)))
+	}
+	return parseOllamaShowContextWindow(body)
+}
+
+// ollamaShowEndpoint derives the native Ollama API root from the
+// OpenAI-compatible base URL Zero stores for the provider (".../v1") and
+// appends /api/show.
+func ollamaShowEndpoint(baseURL string) (string, error) {
+	baseURL = strings.TrimSpace(baseURL)
+	if baseURL == "" {
+		return "", fmt.Errorf("provider base URL is required for ollama model discovery")
+	}
+	parsed, err := url.Parse(baseURL)
+	if err != nil || parsed.Scheme == "" || parsed.Host == "" {
+		return "", fmt.Errorf("invalid provider base URL %q", baseURL)
+	}
+	path := strings.TrimRight(parsed.Path, "/")
+	path = strings.TrimSuffix(path, "/v1")
+	parsed.Path = strings.TrimRight(path, "/") + "/api/show"
+	parsed.RawQuery = ""
+	parsed.Fragment = ""
+	return parsed.String(), nil
+}
+
+// parseOllamaShowContextWindow extracts the context length from an
+// /api/show response. Ollama reports it under model_info with an
+// architecture-prefixed key (e.g. "llama.context_length",
+// "qwen2.context_length") — the prefix varies by model family, so this scans
+// for any key ending in ".context_length" rather than hardcoding one.
+func parseOllamaShowContextWindow(body []byte) (int, error) {
+	// model_info mixes value types (strings like "general.architecture", numbers
+	// like "*.context_length"), so decode values generically and only try to
+	// read a number out of the one key we actually care about.
+	var payload struct {
+		ModelInfo map[string]any `json:"model_info"`
+	}
+	if err := json.Unmarshal(body, &payload); err != nil {
+		return 0, fmt.Errorf("decode ollama show response: %w", err)
+	}
+	for key, value := range payload.ModelInfo {
+		if !strings.HasSuffix(key, ".context_length") {
+			continue
+		}
+		if window, ok := value.(float64); ok && window > 0 {
+			return int(window), nil
+		}
+	}
+	return 0, fmt.Errorf("ollama show response did not report a context length")
+}
+
 func discoverOpenAIModels(ctx context.Context, profile config.ProviderProfile, options Options) ([]Model, error) {
 	endpoint, err := modelsEndpoint(profile.BaseURL)
 	if err != nil {

internal/providermodeldiscovery/discovery_test.go

@@ -2,6 +2,7 @@ package providermodeldiscovery
 
 import (
 	"context"
+	"io"
 	"net/http"
 	"net/http/httptest"
 	"strings"
@@ -267,3 +268,61 @@ func modelIDs(models []Model) []string {
 	}
 	return ids
 }
+
+// TestDiscoverOllamaContextWindowFetchesFromNativeShowEndpoint: the generic
+// /v1/models probe never carries context-window metadata (parseModelsResponse
+// only extracts id/description), so a custom/local Ollama model tag with no
+// curated-catalog match has no other source for it. This exercises the
+// Ollama-native /api/show fallback that fills that gap.
+func TestDiscoverOllamaContextWindowFetchesFromNativeShowEndpoint(t *testing.T) {
+	var gotPath, gotMethod, gotBody string
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		gotPath = r.URL.Path
+		gotMethod = r.Method
+		body, _ := io.ReadAll(r.Body)
+		gotBody = string(body)
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{
+			"model_info": {
+				"general.architecture": "qwen2",
+				"qwen2.context_length": 131072
+			}
+		}`))
+	}))
+	defer server.Close()
+
+	window, err := DiscoverOllamaContextWindow(context.Background(), server.URL+"/v1", "kimi-k2.7-code:cloud", Options{HTTPClient: server.Client()})
+	if err != nil {
+		t.Fatalf("DiscoverOllamaContextWindow returned error: %v", err)
+	}
+	if window != 131072 {
+		t.Fatalf("context window = %d, want 131072", window)
+	}
+	if gotPath != "/api/show" {
+		t.Fatalf("requested path = %q, want /api/show (not under /v1)", gotPath)
+	}
+	if gotMethod != http.MethodPost {
+		t.Fatalf("method = %q, want POST", gotMethod)
+	}
+	if !strings.Contains(gotBody, `"kimi-k2.7-code:cloud"`) {
+		t.Fatalf("request body = %q, want it to name the model", gotBody)
+	}
+}
+
+func TestDiscoverOllamaContextWindowRequiresModelName(t *testing.T) {
+	if _, err := DiscoverOllamaContextWindow(context.Background(), "http://localhost:11434/v1", "", Options{}); err == nil {
+		t.Fatal("expected an error for an empty model name")
+	}
+}
+
+func TestDiscoverOllamaContextWindowErrorsWhenShowOmitsContextLength(t *testing.T) {
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "application/json")
+		_, _ = w.Write([]byte(`{"model_info": {"general.architecture": "qwen2"}}`))
+	}))
+	defer server.Close()
+
+	if _, err := DiscoverOllamaContextWindow(context.Background(), server.URL+"/v1", "some-model", Options{HTTPClient: server.Client()}); err == nil {
+		t.Fatal("expected an error when no *.context_length key is present")
+	}
+}

internal/providers/providerio/providerio.go

@@ -10,6 +10,7 @@ import (
 	"net/url"
 	"os"
 	"regexp"
+	"runtime"
 	"strconv"
 	"strings"
 	"time"
@@ -25,7 +26,7 @@ var ErrStreamIdle = errors.New("idle timeout (upstream stopped sending data)")
 
 // ErrStreamStalled reports that a streaming upstream kept the connection alive
 // (SSE keep-alives reset the idle watchdog, so it never fired) but produced no
-// actual output for streamContentStallFactor × the idle timeout. Without this an
+// actual output for StreamContentStallFactor × the idle timeout. Without this an
 // upstream that heartbeats-but-stalls — observed on chatgpt/gpt-5.x and ollama
 // reasoning models — would hang the agent indefinitely.
 var ErrStreamStalled = errors.New("stream stalled (upstream kept the connection alive but produced no output)")
@@ -38,7 +39,7 @@ var ErrStreamStalled = errors.New("stream stalled (upstream kept the connection
 // stuck or very slow.
 func StreamTimeoutMessage(err error, idleTimeout time.Duration) string {
 	if errors.Is(err, ErrStreamStalled) {
-		return fmt.Sprintf("no output for %s (the model kept the connection alive but produced nothing — it may be stuck; try a faster model or lower reasoning effort)", idleTimeout*streamContentStallFactor)
+		return fmt.Sprintf("no output for %s (the model kept the connection alive but produced nothing — it may be stuck; try a faster model or lower reasoning effort)", idleTimeout*StreamContentStallFactor)
 	}
 	return fmt.Sprintf("idle timeout after %s (upstream stopped sending data)", idleTimeout)
 }
@@ -53,13 +54,13 @@ func StreamTimeoutMessage(err error, idleTimeout time.Duration) string {
 // Override globally with ZERO_STREAM_IDLE_TIMEOUT.
 const DefaultStreamIdleTimeout = 5 * time.Minute
 
-// streamContentStallFactor bounds a heartbeat-but-no-output stream. Keep-alives
+// StreamContentStallFactor bounds a heartbeat-but-no-output stream. Keep-alives
 // reset the idle watchdog (a heartbeating upstream is not "dead"), but if NO real
-// data line arrives for streamContentStallFactor × the idle timeout, the stream is
+// data line arrives for StreamContentStallFactor × the idle timeout, the stream is
 // treated as stalled and aborted (ErrStreamStalled). It is > 1 so a slow-but-
 // producing request — one that emits data between heartbeats — is never killed; the
 // content watchdog only catches a stream that heartbeats while producing nothing.
-const streamContentStallFactor = 2
+const StreamContentStallFactor = 2
 
 // streamIdleTimeoutEnv is the global override for the stream idle timeout. It
 // accepts a Go duration ("5m", "300s", "90s") or a bare number of seconds
@@ -122,6 +123,21 @@ func NormalizeBaseURL(baseURL string, defaultBaseURL string, label string) (stri
 //     unaffected (the stream-idle + content watchdogs cover that).
 //   - IdleConnTimeout is shortened so a connection that went idle across a pause
 //     is closed (and re-dialed fresh) rather than reused after it has gone stale.
+//   - DisableKeepAlives on darwin only: ResponseHeaderTimeout/IdleConnTimeout
+//     above catch a reused connection that's fully dead (never responds) or
+//     idle past the timeout, but not one that's alive-but-severely-degraded —
+//     e.g. reused shortly after a prior request on the same host (well within
+//     30s, common across quick retries of the same turn), where it still
+//     delivers real bytes, just at a crippled rate, resetting Zero's stream
+//     idle/content-stall watchdogs (which only fire on true silence) without
+//     ever recovering. That degraded-not-dead case is indistinguishable from
+//     genuine backend slowness from inside the stream, so the only reliable
+//     fix is removing pooling from the equation entirely on the one platform
+//     where this class of bug has actually reproduced. A fresh TCP+TLS
+//     handshake per request costs low tens of milliseconds — negligible next
+//     to the minutes-long stalls this avoids — and this doesn't touch
+//     Linux/Windows, where the underlying OS doesn't keep dead/degraded
+//     pooled connections around as long.
 var sharedHTTPClient = func() *http.Client {
 	transport := http.DefaultTransport.(*http.Transport).Clone()
 	// 120s, not 60s: a slow cloud proxy (e.g. ollama `*:cloud`) can withhold its
@@ -132,6 +148,7 @@ var sharedHTTPClient = func() *http.Client {
 	// content-stall watchdogs.
 	transport.ResponseHeaderTimeout = 120 * time.Second
 	transport.IdleConnTimeout = 30 * time.Second
+	transport.DisableKeepAlives = runtime.GOOS == "darwin"
 	return &http.Client{Transport: transport}
 }()
 
@@ -285,7 +302,7 @@ func ScanSSEDataWithContext(
 		// Content watchdog: only real data lines reset it (keep-alives do not), so a
 		// stream that heartbeats without producing output is bounded instead of
 		// hanging forever.
-		contentTimeout := idleTimeout * streamContentStallFactor
+		contentTimeout := idleTimeout * StreamContentStallFactor
 		content := time.NewTimer(contentTimeout)
 		defer content.Stop()
 		contentC = content.C

internal/providers/providerio/providerio_test.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"io"
 	"net/http"
+	"runtime"
 	"strings"
 	"testing"
 	"time"
@@ -205,7 +206,7 @@ func TestUpstreamUnreachable(t *testing.T) {
 
 // A heartbeating-but-output-less upstream must not hang forever: SSE keep-alives
 // feed the idle watchdog (so it never fires), but the content watchdog
-// (idleTimeout × streamContentStallFactor) aborts with ErrStreamStalled when no
+// (idleTimeout × StreamContentStallFactor) aborts with ErrStreamStalled when no
 // real data line arrives. This is the gpt-5.x / ollama "still generating forever"
 // hang.
 func TestScanSSEDataWithContextAbortsOnContentStall(t *testing.T) {
@@ -324,6 +325,17 @@ func TestHTTPClientReturnsStallHardenedSharedClient(t *testing.T) {
 	if tr.IdleConnTimeout != 30*time.Second {
 		t.Fatalf("IdleConnTimeout = %v, want 30s", tr.IdleConnTimeout)
 	}
+	// DisableKeepAlives is the stronger mitigation scoped to darwin only: the
+	// two timeouts above catch a reused connection that's fully dead or idle
+	// too long, but not one that's alive-and-degraded (still delivers real
+	// bytes, just at a crippled rate) — which resets Zero's stream watchdogs
+	// without ever recovering. Removing pooling from the equation entirely is
+	// only worth its reconnect cost on the platform this class of bug has
+	// actually reproduced on.
+	wantDisableKeepAlives := runtime.GOOS == "darwin"
+	if tr.DisableKeepAlives != wantDisableKeepAlives {
+		t.Fatalf("DisableKeepAlives = %v, want %v (GOOS=%s)", tr.DisableKeepAlives, wantDisableKeepAlives, runtime.GOOS)
+	}
 	if HTTPClient(nil) != got {
 		t.Fatal("HTTPClient(nil) must return a shared instance so the conn pool is reused")
 	}

internal/specialist/output_tool_test.go

@@ -124,10 +124,16 @@ func TestOutputToolBlocksUntilTaskCompletes(t *testing.T) {
 	tool := NewOutputTool(manager)
 	tool.PollInterval = time.Millisecond
 
+	// timeout is a ceiling, not a target: the test still returns as soon as the
+	// 5ms write lands (PollInterval keeps it responsive), it just tolerates a
+	// slow/contended CI runner without failing. A 100ms budget against a 5ms
+	// write only left 20x margin, which Windows CI runners (coarser default
+	// timer granularity, heavier scheduling contention than Linux/macOS) blew
+	// through and failed the test on an otherwise-unrelated PR merge.
 	result := tool.Run(context.Background(), map[string]any{
 		"task_id": "child_task",
 		"block":   true,
-		"timeout": 100,
+		"timeout": 2000,
 	})
 
 	if result.Status != tools.StatusOK || !strings.Contains(result.Output, "output:\nfinished") {

internal/tools/exec_command.go

@@ -28,8 +28,17 @@ const (
 	completedSessionRetention = 30 * time.Second
 	maxExecSessions           = 64
 	recentExecOutputBytes     = 4096
-	execSessionStopTimeout    = 3 * time.Second
-	execSessionEvictedMessage = "[zero] session evicted: too many background terminals\n"
+	// maxExecOutputBufferBytes caps the undrained output an unpolled session can
+	// accumulate. Without a cap, a long-lived background session nobody polls
+	// again (e.g. a dev server left running after its initiating run was
+	// cancelled) grows this buffer forever as long as the process keeps writing
+	// output, with no ceiling — this previously ran a session's memory into the
+	// tens of gigabytes over several hours and got the whole zero process
+	// OOM-killed by the OS.
+	maxExecOutputBufferBytes         = 2 * 1024 * 1024
+	execSessionStopTimeout           = 3 * time.Second
+	execSessionEvictedMessage        = "[zero] session evicted: too many background terminals\n"
+	execOutputBufferTruncatedMessage = "[zero] output buffer truncated: undrained output exceeded 2MiB, oldest output dropped"
 )
 
 type execSessionManager struct {
@@ -233,6 +242,10 @@ type ExecSessionSnapshot struct {
 	Status       string
 	ExitCode     *int
 	RecentOutput string
+	// OutputTruncated reflects the buffer's last-known truncation state (see
+	// execOutputBuffer.peekTruncated), so a session listing (/ps) still shows
+	// this even if the session is reaped before ever being polled again.
+	OutputTruncated bool
 }
 
 type ExecSessionController interface {
@@ -317,24 +330,26 @@ func (session *execSession) snapshot() ExecSessionSnapshot {
 		status = "exited"
 	}
 	return ExecSessionSnapshot{
-		ID:           session.id,
-		Command:      session.commandText,
-		Cwd:          session.cwd,
-		RelativeCwd:  session.relativeCwd,
-		StartedAt:    startedAt,
-		LastUsedAt:   lastUsedAt,
-		TTY:          session.tty,
-		Status:       status,
-		ExitCode:     copiedExit,
-		RecentOutput: session.output.recentString(),
+		ID:              session.id,
+		Command:         session.commandText,
+		Cwd:             session.cwd,
+		RelativeCwd:     session.relativeCwd,
+		StartedAt:       startedAt,
+		LastUsedAt:      lastUsedAt,
+		TTY:             session.tty,
+		Status:          status,
+		ExitCode:        copiedExit,
+		RecentOutput:    session.output.recentString(),
+		OutputTruncated: session.output.peekTruncated(),
 	}
 }
 
 type execOutputBuffer struct {
-	mu     sync.Mutex
-	data   []byte
-	recent []byte
-	notify chan struct{}
+	mu        sync.Mutex
+	data      []byte
+	recent    []byte
+	truncated bool
+	notify    chan struct{}
 }
 
 func newExecOutputBuffer() *execOutputBuffer {
@@ -344,6 +359,10 @@ func newExecOutputBuffer() *execOutputBuffer {
 func (buffer *execOutputBuffer) Write(p []byte) (int, error) {
 	buffer.mu.Lock()
 	buffer.data = append(buffer.data, p...)
+	if len(buffer.data) > maxExecOutputBufferBytes {
+		buffer.data = buffer.data[len(buffer.data)-maxExecOutputBufferBytes:]
+		buffer.truncated = true
+	}
 	buffer.recent = append(buffer.recent, p...)
 	if len(buffer.recent) > recentExecOutputBytes {
 		buffer.recent = buffer.recent[len(buffer.recent)-recentExecOutputBytes:]
@@ -373,6 +392,34 @@ func (buffer *execOutputBuffer) drainString() string {
 	return out
 }
 
+// consumeTruncated reports whether the buffer has dropped output to stay
+// within maxExecOutputBufferBytes since the last call, resetting the flag.
+// Kept as an out-of-band signal rather than text embedded in drainString's
+// result: an earlier version prefixed a notice directly into the drained
+// string, but that notice always sat ~maxExecOutputBufferBytes (2MiB) before
+// the end of the combined output, far outside the byte-budget head/tail
+// window truncateExecOutput keeps afterward (at most 400KB even at the
+// tool's maximum max_output_tokens) — so the notice was reliably swallowed
+// or chopped by that second, unrelated truncation pass. Surfacing it as a
+// separate bool lets the caller report it regardless of where in the byte
+// stream the overflow happened.
+func (buffer *execOutputBuffer) consumeTruncated() bool {
+	buffer.mu.Lock()
+	defer buffer.mu.Unlock()
+	truncated := buffer.truncated
+	buffer.truncated = false
+	return truncated
+}
+
+// peekTruncated reports the buffer's last-known truncation state without
+// clearing it, for status views (e.g. /ps) that shouldn't consume the signal
+// a subsequent poll is still meant to report via consumeTruncated.
+func (buffer *execOutputBuffer) peekTruncated() bool {
+	buffer.mu.Lock()
+	defer buffer.mu.Unlock()
+	return buffer.truncated
+}
+
 type execCommandTool struct {
 	baseTool
 	workspaceRoot string
@@ -485,25 +532,28 @@ func (tool execCommandTool) run(ctx context.Context, args map[string]any, engine
 	if err != nil {
 		return errorResult("Error starting exec_command: " + err.Error())
 	}
-	output := session.collect(ctx, time.Duration(yieldTimeMS)*time.Millisecond)
+	output, outputTruncated := session.collect(ctx, time.Duration(yieldTimeMS)*time.Millisecond)
 	if ctx != nil && ctx.Err() != nil && !session.doneClosed() {
 		session.terminate()
-		output += session.collect(context.Background(), time.Second)
+		more, moreTruncated := session.collect(context.Background(), time.Second)
+		output += more
+		outputTruncated = outputTruncated || moreTruncated
 	}
 	exitCode, exited := session.exitStatus()
 	if exited {
 		tool.manager.remove(session.id)
 	}
 	return execToolResult(execToolResultInput{
-		commandText:     commandText,
-		output:          output,
-		sessionID:       session.id,
-		exitCode:        exitCode,
-		exited:          exited,
-		relativeCwd:     relativeCwd,
-		tty:             session.tty,
-		plan:            session.plan,
-		maxOutputTokens: maxOutputTokens,
+		commandText:           commandText,
+		output:                output,
+		outputBufferTruncated: outputTruncated,
+		sessionID:             session.id,
+		exitCode:              exitCode,
+		exited:                exited,
+		relativeCwd:           relativeCwd,
+		tty:                   session.tty,
+		plan:                  session.plan,
+		maxOutputTokens:       maxOutputTokens,
 	})
 }
 
@@ -558,26 +608,49 @@ func (tool execCommandTool) startSession(commandText string, absoluteCwd string,
 	return session, nil
 }
 
-func (session *execSession) collect(ctx context.Context, wait time.Duration) string {
+// collect drains the session's output buffer, returning the accumulated text
+// and whether the buffer ever had to drop output to stay within
+// maxExecOutputBufferBytes since the last collect call.
+func (session *execSession) collect(ctx context.Context, wait time.Duration) (string, bool) {
 	if ctx == nil {
 		ctx = context.Background()
 	}
 	deadline := time.Now().Add(wait)
 	var builder strings.Builder
+	truncated := false
+	finish := func() (string, bool) {
+		if session.output.consumeTruncated() {
+			truncated = true
+		}
+		return builder.String(), truncated
+	}
 	for {
 		if chunk := session.output.drainString(); chunk != "" {
 			builder.WriteString(chunk)
+			if session.output.consumeTruncated() {
+				truncated = true
+			}
+			// A background process that keeps writing output faster than this
+			// loop can drain it (a chatty dev server, a watch-mode rebuild loop,
+			// a crash-restart spew) would otherwise never let drainString return
+			// empty, so the deadline check below — only reached on an empty
+			// drain — would never fire. That turns `wait` into an unbounded
+			// block regardless of what the caller asked for. Check it here too,
+			// so continuous output can never starve the timeout.
+			if time.Now().After(deadline) {
+				return finish()
+			}
 			continue
 		}
 		if session.doneClosed() {
 			if chunk := session.output.drainString(); chunk != "" {
 				builder.WriteString(chunk)
 			}
-			return builder.String()
+			return finish()
 		}
 		remaining := time.Until(deadline)
 		if remaining <= 0 {
-			return builder.String()
+			return finish()
 		}
 		timer := time.NewTimer(remaining)
 		select {
@@ -602,9 +675,9 @@ func (session *execSession) collect(ctx context.Context, wait time.Duration) str
 				default:
 				}
 			}
-			return builder.String()
+			return finish()
 		case <-timer.C:
-			return builder.String()
+			return finish()
 		}
 	}
 }
@@ -701,22 +774,23 @@ func (tool writeStdinTool) RunWithOptions(ctx context.Context, args map[string]a
 			}
 		}
 	}
-	output := session.collect(ctx, time.Duration(yieldTimeMS)*time.Millisecond)
+	output, outputTruncated := session.collect(ctx, time.Duration(yieldTimeMS)*time.Millisecond)
 	exitCode, exited := session.exitStatus()
 	if exited {
 		tool.manager.remove(session.id)
 	}
 	return execToolResult(execToolResultInput{
-		commandText:     session.commandText,
-		output:          output,
-		sessionID:       session.id,
-		exitCode:        exitCode,
-		exited:          exited,
-		relativeCwd:     session.relativeCwd,
-		tty:             session.tty,
-		interrupted:     interrupted,
-		plan:            session.plan,
-		maxOutputTokens: maxOutputTokens,
+		commandText:           session.commandText,
+		output:                output,
+		outputBufferTruncated: outputTruncated,
+		sessionID:             session.id,
+		exitCode:              exitCode,
+		exited:                exited,
+		relativeCwd:           session.relativeCwd,
+		tty:                   session.tty,
+		interrupted:           interrupted,
+		plan:                  session.plan,
+		maxOutputTokens:       maxOutputTokens,
 	})
 }
 
@@ -741,16 +815,22 @@ func shouldInterruptExecSession(chars string, tty bool) bool {
 }
 
 type execToolResultInput struct {
-	commandText     string
-	output          string
-	sessionID       int
-	exitCode        int
-	exited          bool
-	relativeCwd     string
-	tty             bool
-	interrupted     bool
-	plan            zeroSandbox.CommandPlan
-	maxOutputTokens int
+	commandText string
+	output      string
+	// outputBufferTruncated is true when the session's undrained output buffer
+	// had to drop bytes to stay within maxExecOutputBufferBytes since it was
+	// last collected — data that is gone for good, unlike the head/tail
+	// truncation below (which the caller can recover by polling again or
+	// raising max_output_tokens).
+	outputBufferTruncated bool
+	sessionID             int
+	exitCode              int
+	exited                bool
+	relativeCwd           string
+	tty                   bool
+	interrupted           bool
+	plan                  zeroSandbox.CommandPlan
+	maxOutputTokens       int
 }
 
 func execToolResult(input execToolResultInput) Result {
@@ -771,16 +851,26 @@ func execToolResult(input execToolResultInput) Result {
 	} else {
 		meta["session_id"] = strconv.Itoa(input.sessionID)
 	}
+	if input.outputBufferTruncated {
+		meta["output_buffer_truncated"] = "true"
+	}
 
 	status := StatusOK
 	if input.exited && ((input.exitCode != 0 && !input.interrupted) || meta[SandboxLikelyDeniedMeta] == "true") {
 		status = StatusError
 	}
 	body := formatExecCommandOutput(output, input.sessionID, input.exited, input.exitCode, input.interrupted)
+	if input.outputBufferTruncated {
+		// Appended after truncateExecOutput's own head/tail slicing, not
+		// embedded in the text that goes through it — a marker inside that
+		// text can land in the discarded middle or get chopped at a small
+		// max_output_tokens budget. Appending here guarantees it survives.
+		body += "\n" + execOutputBufferTruncatedMessage
+	}
 	return Result{
 		Status:    status,
 		Output:    body,
-		Truncated: truncated,
+		Truncated: truncated || input.outputBufferTruncated,
 		Meta:      meta,
 		Display: Display{
 			Summary: execDisplaySummary(input.commandText, input.sessionID, input.exited, input.exitCode),

internal/tools/exec_command_test.go

@@ -363,6 +363,152 @@ func TestStartExecProcessFallsBackAfterPTYStartMutation(t *testing.T) {
 	}
 }
 
+// TestExecOutputBufferCapsUndrainedData: a session nobody polls must not grow
+// its undrained buffer without bound — a long-lived background process that
+// keeps writing while unpolled previously ran a session's memory into the
+// tens of gigabytes and got the whole zero process OOM-killed by the OS.
+func TestExecOutputBufferCapsUndrainedData(t *testing.T) {
+	buffer := newExecOutputBuffer()
+
+	chunk := strings.Repeat("x", 1024)
+	writes := (maxExecOutputBufferBytes / len(chunk)) + 10 // comfortably over the cap
+	for i := 0; i < writes; i++ {
+		if _, err := buffer.Write([]byte(chunk)); err != nil {
+			t.Fatalf("Write: %v", err)
+		}
+	}
+
+	buffer.mu.Lock()
+	dataLen := len(buffer.data)
+	buffer.mu.Unlock()
+	if dataLen > maxExecOutputBufferBytes {
+		t.Fatalf("undrained buffer grew to %d bytes, want <= %d", dataLen, maxExecOutputBufferBytes)
+	}
+
+	out := buffer.drainString()
+	// drainString itself carries no truncation marker: a marker embedded in
+	// the drained text would always sit ~maxExecOutputBufferBytes before the
+	// end of the string, past any realistic head/tail truncation window a
+	// caller applies afterward (see execToolResult), so it's reliably lost.
+	// The signal lives out of band on consumeTruncated/peekTruncated instead.
+	if !strings.HasSuffix(out, chunk) {
+		t.Fatal("drained output should keep the most recent bytes, not the oldest")
+	}
+	if len(out) > maxExecOutputBufferBytes {
+		t.Fatalf("drained output = %d bytes, want <= %d (no marker text mixed in)", len(out), maxExecOutputBufferBytes)
+	}
+
+	if !buffer.peekTruncated() {
+		t.Fatal("peekTruncated should report the overflow without clearing it")
+	}
+	if !buffer.peekTruncated() {
+		t.Fatal("a second peekTruncated call should still report it — peek must not consume")
+	}
+	if !buffer.consumeTruncated() {
+		t.Fatal("consumeTruncated should report the overflow")
+	}
+	if buffer.consumeTruncated() {
+		t.Fatal("consumeTruncated should reset after being read once")
+	}
+	if buffer.peekTruncated() {
+		t.Fatal("peekTruncated should reflect the reset state after consumeTruncated")
+	}
+
+	// A second drain with no intervening writes must be empty.
+	if got := buffer.drainString(); got != "" {
+		t.Fatalf("drainString after a full drain = %q, want empty", got)
+	}
+}
+
+// TestExecToolResultSurfacesBufferTruncationOutsideByteBudget: an earlier
+// version embedded the truncation notice directly in the drained text, which
+// a review found sits ~maxExecOutputBufferBytes before the end of the
+// string — far past the head/tail window truncateExecOutput keeps even at
+// the tool's smallest allowed max_output_tokens, so the notice was reliably
+// swallowed or chopped. The notice must survive regardless of how small the
+// byte budget is, and it must not count against that budget.
+func TestExecToolResultSurfacesBufferTruncationOutsideByteBudget(t *testing.T) {
+	hugeOutput := strings.Repeat("y", maxExecOutputBufferBytes+1024)
+
+	result := execToolResult(execToolResultInput{
+		commandText:           "cmd",
+		output:                hugeOutput,
+		outputBufferTruncated: true,
+		sessionID:             1,
+		exited:                false,
+		maxOutputTokens:       1, // the schema's own declared minimum
+	})
+
+	if !strings.Contains(result.Output, execOutputBufferTruncatedMessage) {
+		t.Fatalf("result output should contain the buffer-truncation notice even at the smallest max_output_tokens, got %q", result.Output[:min(len(result.Output), 200)])
+	}
+	if result.Meta["output_buffer_truncated"] != "true" {
+		t.Fatalf("result meta should flag output_buffer_truncated, got %#v", result.Meta)
+	}
+	if !result.Truncated {
+		t.Fatal("result should report Truncated when the buffer dropped output")
+	}
+}
+
+// TestCollectRespectsDeadlineUnderContinuousOutput asserts collect() returns
+// close to its requested deadline even while output keeps arriving. Before
+// the corresponding fix, the deadline was only checked in the branch reached
+// when drainString returns empty — a background process producing output
+// fast/continuously enough to keep the buffer perpetually non-empty could
+// theoretically starve that check indefinitely. This synthetic writer
+// (8 goroutines, tight loop) did not reliably reproduce that starvation under
+// Go's scheduler in practice — the reader still won the race often enough —
+// so this test doesn't prove the old code could hang; it just pins down the
+// intended behavior (bounded by wait) going forward.
+func TestCollectRespectsDeadlineUnderContinuousOutput(t *testing.T) {
+	session := &execSession{
+		id:     1000,
+		output: newExecOutputBuffer(),
+		done:   make(chan struct{}),
+	}
+
+	stop := make(chan struct{})
+	var wg sync.WaitGroup
+	// Several concurrent writers, each pushing a decent-sized chunk in a tight
+	// loop: a single slow writer lets the reader win the race often enough
+	// (the runtime schedules a gap between writes) to mask the bug. Enough
+	// parallel writers keep the buffer non-empty essentially continuously,
+	// closer to a real chatty process whose PTY reads land in bursts.
+	const writers = 8
+	chunk := []byte(strings.Repeat("x", 256))
+	wg.Add(writers)
+	for i := 0; i < writers; i++ {
+		go func() {
+			defer wg.Done()
+			for {
+				select {
+				case <-stop:
+					return
+				default:
+					session.output.Write(chunk)
+				}
+			}
+		}()
+	}
+	t.Cleanup(func() {
+		close(stop)
+		wg.Wait()
+	})
+
+	const wait = 200 * time.Millisecond
+	start := time.Now()
+	_, _ = session.collect(context.Background(), wait)
+	elapsed := time.Since(start)
+
+	// Generous slack over `wait` for scheduling jitter under a continuously
+	// writing goroutine — this must stay a small multiple of wait, not
+	// "however long the writer keeps going" (which is what the bug produced:
+	// this test would hang past the 30s test timeout without the fix).
+	if elapsed > 3*wait {
+		t.Fatalf("collect took %v under continuous output, want close to the %v deadline", elapsed, wait)
+	}
+}
+
 // resilientTempDir is like t.TempDir() but tolerates the Windows handle-release
 // lag: a SIGKILL'd child process that had the dir as its cwd may not have
 // released it the instant it is reaped, so the immediate RemoveAll t.TempDir()

internal/tui/background_terminals.go

@@ -146,6 +146,9 @@ func formatBackgroundTerminalRow(session tools.ExecSessionSnapshot, now time.Tim
 	}
 	preview := compactCommandOutputText(session.RecentOutput)
 	prefix := fmt.Sprintf("%d · %s · %s · %s", session.ID, session.Status, age, cwd)
+	if session.OutputTruncated {
+		prefix += " · output truncated"
+	}
 	if preview != "" {
 		return prefix + " · " + command + " · " + preview
 	}

internal/tui/clipboard.go

@@ -56,6 +56,13 @@ func pasteFromClipboardCmd() tea.Cmd {
 // spec prompt, the MCP manager, an open picker, the detailed transcript) swallow
 // the paste; empty content is a no-op.
 func (m model) routePaste(content string) (tea.Model, tea.Cmd) {
+	// A paste is a deliberate action, same as a keypress or click — it means
+	// the user moved on to something else, so it disarms a stale Esc
+	// cancel-confirmation. tea.PasteMsg/clipboardReadMsg aren't
+	// tea.KeyPressMsg, so they don't go through that generic keypress hook;
+	// do it once here, before any early return, so both the bracketed-paste
+	// and right-click-paste paths are covered uniformly.
+	m = m.disarmCancelConfirmation()
 	if content == "" {
 		// Empty text clipboard — the user may have pasted a screenshot.
 		// Probe the OS clipboard for image content asynchronously.

internal/tui/command_center.go

@@ -490,16 +490,16 @@ func (m model) handleModelCommand(args string) (model, string) {
 // picker calls this when a model from a non-active provider is chosen, so the
 // picker can list every saved provider and switch across them (like a unified
 // provider+model selector). The key is loaded from the encrypted store / env.
-func (m model) switchProviderModel(providerName, modelID string) (model, string) {
+func (m model) switchProviderModel(providerName, modelID string) (model, string, tea.Cmd) {
 	if m.pending {
-		return m, "Model\nCannot switch providers while a run is active."
+		return m, "Model\nCannot switch providers while a run is active.", nil
 	}
 	if m.newProvider == nil {
-		return m, "Model\nProvider rebuild is not available for this TUI session."
+		return m, "Model\nProvider rebuild is not available for this TUI session.", nil
 	}
 	target, ok := m.savedProviderByName(providerName)
 	if !ok {
-		return m, "Model\nunknown provider " + strconv.Quote(providerName)
+		return m, "Model\nunknown provider " + strconv.Quote(providerName), nil
 	}
 	target = m.profileWithCredential(target)
 	target.Model = strings.TrimSpace(modelID)
@@ -508,11 +508,11 @@ func (m model) switchProviderModel(providerName, modelID string) (model, string)
 	// was deleted/unreadable the marker can still be set, and building a keyless
 	// provider would only fail later with a 401. Local/no-auth providers need no key.
 	if strings.TrimSpace(target.APIKey) == "" && strings.TrimSpace(target.AuthHeaderValue) == "" && !(hasDescriptor && descriptor.Local) {
-		return m, "Model\nprovider " + strconv.Quote(providerName) + " has no usable credential — run setup or `zero auth login " + providerName + "`."
+		return m, "Model\nprovider " + strconv.Quote(providerName) + " has no usable credential — run setup or `zero auth login " + providerName + "`.", nil
 	}
 	next, err := m.newProvider(target)
 	if err != nil {
-		return m, "Model\n" + redaction.RedactString(err.Error(), redaction.Options{ExtraSecretValues: []string{target.APIKey}})
+		return m, "Model\n" + redaction.RedactString(err.Error(), redaction.Options{ExtraSecretValues: []string{target.APIKey}}), nil
 	}
 	m.provider = next
 	m.providerProfile = target
@@ -524,7 +524,19 @@ func (m model) switchProviderModel(providerName, modelID string) (model, string)
 		_, _ = config.SetActiveProvider(m.userConfigPath, target.Name)
 		_, _ = config.SetProviderModel(m.userConfigPath, target.Name, target.Model)
 	}
-	return m, fmt.Sprintf("Model\nSwitched to %s · %s", target.Name, target.Model)
+	// Warm discovery for the provider we just switched to, same as Init() does
+	// for the provider active at launch — otherwise the context-usage gauge has
+	// no window for this provider until /model happens to be opened separately.
+	var cmds []tea.Cmd
+	if hasDescriptor {
+		if cmd := m.modelPickerProviderDiscoveryCmd(descriptor, target); cmd != nil {
+			cmds = append(cmds, cmd)
+		}
+		if cmd := m.ollamaContextWindowDiscoveryCmd(descriptor, target.BaseURL, target.Model); cmd != nil {
+			cmds = append(cmds, cmd)
+		}
+	}
+	return m, fmt.Sprintf("Model\nSwitched to %s · %s", target.Name, target.Model), tea.Batch(cmds...)
 }
 
 // profileWithCredential fills a profile's APIKey for provider construction the same

internal/tui/commands.go

@@ -281,9 +281,9 @@ var commandDefinitions = []commandDefinition{
 	},
 	{
 		name:        "/theme",
-		usage:       "/theme [auto|dark|light]",
+		usage:       "/theme [list|auto|name]",
 		group:       commandGroupSession,
-		description: "Switch or show the color theme (auto-detects terminal background).",
+		description: "Pick a color theme (no arg opens the picker; auto detects the terminal background).",
 		kind:        commandTheme,
 	},
 	{

internal/tui/context_gauge_test.go

@@ -27,3 +27,29 @@ func TestContextWindowSegment(t *testing.T) {
 		t.Fatalf("gauge = %q, want 161K/200K · 81%%", got)
 	}
 }
+
+// TestStatusLineDoesNotDuplicateTokenFigureNextToGauge: the gauge's "used"
+// figure and the plain usage segment's token count both read the exact same
+// latestUsageTokens value — once the gauge is showing it, the usage segment
+// must fall back to cost-only, or the same number renders twice side by
+// side in the footer (e.g. "◔ 161K/200K · 81% │ 161K tok").
+func TestStatusLineDoesNotDuplicateTokenFigureNextToGauge(t *testing.T) {
+	m := newModel(t.Context(), Options{ModelName: "claude-sonnet-4.5"})
+	if _, err := m.usageTracker.Record(usage.RecordInput{
+		ModelID: "claude-sonnet-4.5",
+		Usage:   zeroruntime.Usage{InputTokens: 160_000, OutputTokens: 1000},
+	}); err != nil {
+		t.Fatalf("Record: %v", err)
+	}
+
+	status := plainRender(t, m.statusLine(110))
+	if !strings.Contains(status, "161K/200K") {
+		t.Fatalf("status line = %q, expected the context gauge to render", status)
+	}
+	if strings.Count(status, "161K") != 1 {
+		t.Fatalf("status line = %q, the 161K token figure must appear exactly once, not duplicated next to the gauge", status)
+	}
+	if strings.Contains(status, "tok") {
+		t.Fatalf("status line = %q, the plain token segment should be suppressed once the gauge shows the same figure", status)
+	}
+}

internal/tui/flush_test.go

@@ -122,6 +122,8 @@ func TestEscCancellationLeavesVisibleMarker(t *testing.T) {
 
 	updated, _ := m.Update(testKey(tea.KeyEsc))
 	next := updated.(model)
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
 	if !transcriptContains(next.transcript, "Run cancelled.") {
 		t.Fatalf("expected visible cancellation marker, got %#v", next.transcript)
 	}

internal/tui/init_window_size_test.go

@@ -0,0 +1,59 @@
+package tui
+
+import (
+	"context"
+	"reflect"
+	"testing"
+
+	tea "charm.land/bubbletea/v2"
+)
+
+// TestInitRequestsWindowSize: Bubble Tea documents an initial WindowSizeMsg as
+// delivered automatically on program start, but that's the terminal
+// proactively pushing a size — if it's ever missed (a slow/unusual terminal,
+// a multiplexer, a startup race), nothing else asks again, m.height stays 0
+// forever, and transcriptView's `if m.altScreen && m.height > 0` gate falls
+// back to the unpadded, non-fullscreen render path for the whole session (the
+// alt-screen viewport never gets filled below the actual content). Init must
+// explicitly request it too, the same way it already explicitly requests the
+// background color rather than relying solely on an unprompted push.
+func TestInitRequestsWindowSize(t *testing.T) {
+	m := newModel(context.Background(), Options{ModelName: "gpt-4"})
+	cmd := m.Init()
+	if cmd == nil {
+		t.Fatal("Init() must return a non-nil command")
+	}
+
+	want := reflect.ValueOf(tea.RequestWindowSize).Pointer()
+	if !batchContainsCmd(t, cmd, want) {
+		t.Error("Init() must request the window size (tea.RequestWindowSize), not rely solely on the terminal's unprompted initial WindowSizeMsg")
+	}
+}
+
+// batchContainsCmd reports whether cmd (Init()'s single top-level
+// tea.Batch(...)) contains a sub-command matching want, compared by pointer
+// (the same technique TestThemeAutoReProbesBackground uses for
+// tea.RequestBackgroundColor — reliable for named top-level functions like
+// tea.RequestWindowSize, not closures). Invokes cmd itself once to unpack the
+// tea.BatchMsg, but only pointer-compares the sub-commands — never calls
+// them, since Init()'s batch also carries real closures (e.g. provider model
+// discovery) that make live network calls and must not fire in a unit test.
+func batchContainsCmd(t *testing.T, cmd tea.Cmd, want uintptr) bool {
+	t.Helper()
+	if cmd == nil {
+		return false
+	}
+	if reflect.ValueOf(cmd).Pointer() == want {
+		return true
+	}
+	batch, ok := cmd().(tea.BatchMsg)
+	if !ok {
+		return false
+	}
+	for _, sub := range batch {
+		if sub != nil && reflect.ValueOf(sub).Pointer() == want {
+			return true
+		}
+	}
+	return false
+}

internal/tui/keybinding_help.go

@@ -31,7 +31,7 @@ var keybindingGroups = []keybindingGroup{
 		bindings: []keybinding{
 			{"Enter", "send the message"},
 			{"Alt+Enter", "insert a newline (multi-line compose)"},
-			{"Esc", "cancel the run / dismiss a popup / clear the input"},
+			{"Esc (×2)", "cancel the run / dismiss a popup / clear the input"},
 			{"Ctrl+C", "cancel the run, then quit"},
 			{"?", "show this help (on an empty input)"},
 		},

internal/tui/model.go

@@ -25,6 +25,7 @@ import (
 	"github.com/Gitlawb/zero/internal/notify"
 	"github.com/Gitlawb/zero/internal/providerhealth"
 	"github.com/Gitlawb/zero/internal/providermodeldiscovery"
+	"github.com/Gitlawb/zero/internal/providers/providerio"
 	"github.com/Gitlawb/zero/internal/sandbox"
 	"github.com/Gitlawb/zero/internal/sessions"
 	"github.com/Gitlawb/zero/internal/streamjson"
@@ -40,6 +41,15 @@ const chatWheelScrollLines = 5
 const ctrlCExitConfirmDuration = 3 * time.Second
 const ctrlCExitConfirmText = "Press Ctrl+C again to exit"
 
+// escCancelConfirmDuration/escCancelConfirmText guard Esc cancelling a running
+// turn, mirroring ctrlCExitConfirmDuration/ctrlCExitConfirmText's pattern (same
+// window, same amber footer treatment) so the two "stop it" keybinds feel
+// consistent. Without this, a single stray Esc — e.g. meant to dismiss a
+// suggestion overlay that had already closed — silently threw away an
+// in-progress run with no chance to reconsider.
+const escCancelConfirmDuration = 3 * time.Second
+const escCancelConfirmText = "Press Esc again to cancel"
+
 // dragEdgeScrollInterval/dragEdgeScrollStep drive the smooth-glide auto-scroll
 // while a drag holds past the transcript edge (see edgeScrollDelta). A small step
 // on a short, steady cadence reads as a smooth continuous scroll; the wheel-scroll
@@ -48,40 +58,41 @@ const dragEdgeScrollInterval = 70 * time.Millisecond
 const dragEdgeScrollStep = 1
 
 type model struct {
-	ctx                    context.Context
-	cwd                    string
-	userCommands           []usercommands.Command // file-sourced /commands (.zero/commands)
-	userConfigPath         string
-	doctorUserConfigPath   string
-	projectConfigPath      string
-	gitBranch              string
-	providerName           string
-	modelName              string
-	providerProfile        config.ProviderProfile
-	savedProviders         []config.ProviderProfile
-	provider               zeroruntime.Provider
-	newProvider            func(config.ProviderProfile) (zeroruntime.Provider, error)
-	probeProviderHealth    func(context.Context, providerhealth.Options) providerhealth.Result
-	discoverProviderModels func(context.Context, config.ProviderProfile) ([]providermodeldiscovery.Model, error)
-	registry               *tools.Registry
-	sessionStore           *sessions.Store
-	sandboxStore           *sandbox.GrantStore
-	mcpConfig              config.MCPConfig
-	mcpPermissionStore     *internalmcp.PermissionStore
-	mcpTokenStore          *internalmcp.TokenStore
-	mcpCommand             func(context.Context, []string) MCPCommandResult
-	sandboxSetupCommand    func(context.Context) SandboxSetupCommandResult
-	mcpViewStateCache      MCPViewState
-	mcpViewStateReady      bool
-	mcpCommandSeq          int
-	mcpCommandCancel       context.CancelFunc
-	sandboxSetupSeq        int
-	sandboxSetupInFlight   bool
-	doctorCommandSeq       int
-	doctorInFlight         bool
-	doctorFrame            int
-	activeSession          sessions.Metadata
-	sessionEvents          []sessions.Event
+	ctx                         context.Context
+	cwd                         string
+	userCommands                []usercommands.Command // file-sourced /commands (.zero/commands)
+	userConfigPath              string
+	doctorUserConfigPath        string
+	projectConfigPath           string
+	gitBranch                   string
+	providerName                string
+	modelName                   string
+	providerProfile             config.ProviderProfile
+	savedProviders              []config.ProviderProfile
+	provider                    zeroruntime.Provider
+	newProvider                 func(config.ProviderProfile) (zeroruntime.Provider, error)
+	probeProviderHealth         func(context.Context, providerhealth.Options) providerhealth.Result
+	discoverProviderModels      func(context.Context, config.ProviderProfile) ([]providermodeldiscovery.Model, error)
+	discoverOllamaContextWindow func(ctx context.Context, baseURL string, model string) (int, error)
+	registry                    *tools.Registry
+	sessionStore                *sessions.Store
+	sandboxStore                *sandbox.GrantStore
+	mcpConfig                   config.MCPConfig
+	mcpPermissionStore          *internalmcp.PermissionStore
+	mcpTokenStore               *internalmcp.TokenStore
+	mcpCommand                  func(context.Context, []string) MCPCommandResult
+	sandboxSetupCommand         func(context.Context) SandboxSetupCommandResult
+	mcpViewStateCache           MCPViewState
+	mcpViewStateReady           bool
+	mcpCommandSeq               int
+	mcpCommandCancel            context.CancelFunc
+	sandboxSetupSeq             int
+	sandboxSetupInFlight        bool
+	doctorCommandSeq            int
+	doctorInFlight              bool
+	doctorFrame                 int
+	activeSession               sessions.Metadata
+	sessionEvents               []sessions.Event
 	// titledSessions records session ids for which a model-generated title has
 	// already been attempted this process, so a finished turn re-fires the title
 	// generator at most once per session (even before its async result lands).
@@ -296,6 +307,14 @@ type model struct {
 	copyStatusSeq     int
 	exitConfirmActive bool
 	exitConfirmSeq    int
+	// cancelConfirmActive/cancelConfirmSeq mirror exitConfirmActive/exitConfirmSeq
+	// (same seq-gated tea.Tick pattern) but guard a DIFFERENT action: Esc
+	// cancelling a running turn. The two are deliberately separate state (not a
+	// shared flag) since they're different actions with different consequences
+	// (quit the app vs. cancel the current run) that are armed by different
+	// keys — Ctrl+C and Esc respectively.
+	cancelConfirmActive bool
+	cancelConfirmSeq    int
 	// edgeScrollDelta drives the smooth-glide auto-scroll while a drag holds past
 	// the transcript's top/bottom edge: 0 when idle, else the signed per-tick step
 	// (matches transcriptEdgeScrollDelta's sign convention). A self-scheduling
@@ -330,6 +349,12 @@ type model struct {
 	// catalog descriptor ID), so /model shows each provider's real current models —
 	// the same list the provider-setup wizard discovers — not the static catalog.
 	modelPickerLiveByProvider map[string][]providermodeldiscovery.Model
+	// ollamaContextWindowByModel holds context-window sizes fetched from a local
+	// Ollama daemon's native /api/show endpoint (keyed by model name), for
+	// custom/local models that have no curated-catalog entry and whose
+	// OpenAI-compatible /v1/models listing doesn't carry that metadata at all —
+	// see modelContextWindow.
+	ollamaContextWindowByModel map[string]int
 
 	// pendingImages holds image attachments staged by /image for the next user
 	// turn; pendingImageLabels are their display names (base(path)) for the chip
@@ -358,6 +383,12 @@ type exitConfirmExpiredMsg struct {
 	seq int
 }
 
+// cancelConfirmExpiredMsg mirrors exitConfirmExpiredMsg for the Esc
+// cancel-a-run confirmation (see cancelConfirmActive).
+type cancelConfirmExpiredMsg struct {
+	seq int
+}
+
 // dragEdgeScrollTickMsg advances the smooth-glide auto-scroll one step (see
 // edgeScrollDelta). seq must match m.edgeScrollSeq or the tick is stale (the
 // drag moved back into the body, released, or was otherwise stopped since this
@@ -645,56 +676,57 @@ func newModel(ctx context.Context, options Options) model {
 	notifier.SetFocused(true)
 
 	m := model{
-		ctx:                    ctx,
-		cwd:                    cwd,
-		swarmDoneAt:            map[string]time.Time{},
-		userCommands:           loadedUserCommands,
-		composerCursorVisible:  true,
-		userConfigPath:         options.UserConfigPath,
-		doctorUserConfigPath:   doctorUserConfigPath,
-		projectConfigPath:      options.ProjectConfigPath,
-		savedProviders:         options.SavedProviders,
-		gitBranch:              gitBranch(cwd),
-		providerName:           options.ProviderName,
-		modelName:              options.ModelName,
-		providerProfile:        options.ProviderProfile,
-		favoriteModels:         favoriteModelSet(options.FavoriteModels),
-		recapsEnabled:          options.RecapsEnabled,
-		provider:               options.Provider,
-		newProvider:            options.NewProvider,
-		probeProviderHealth:    options.ProbeProviderHealth,
-		discoverProviderModels: options.DiscoverProviderModels,
-		registry:               registry,
-		sessionStore:           sessionStore,
-		sandboxStore:           sandboxStore,
-		mcpConfig:              options.MCPConfig,
-		mcpPermissionStore:     options.MCPPermissionStore,
-		mcpTokenStore:          options.MCPTokenStore,
-		mcpCommand:             options.MCPCommand,
-		sandboxSetupCommand:    options.SandboxSetupCommand,
-		agentOptions:           options.AgentOptions,
-		sessionCompactor:       options.SessionCompactor,
-		runtimeMessageSink:     options.RuntimeMessageSink,
-		permissionMode:         permissionMode,
-		reasoningEffort:        options.ReasoningEffort,
-		responseStyle:          defaultedResponseStyle(options.ResponseStyle),
-		themeMode:              resolveThemeMode(options.Theme, os.Getenv("ZERO_THEME")),
-		hasDarkBg:              true,
-		userAgent:              options.UserAgent,
-		usageTracker:           usageTracker,
-		transcript:             initialTranscript(),
-		transcriptBodyHeights:  newTranscriptBodyHeightCache(defaultTranscriptBodyHeightCacheMaxEntries),
-		prService:              prService,
-		prState:                prService.GetState(),
-		input:                  input,
-		spinner:                runSpinner,
-		now:                    time.Now,
-		notifier:               notifier,
-		altScreen:              options.AltScreen,
-		liveUsageCounts:        map[int]int{},
-		swarmSessionMap:        map[string]string{},
-		setup:                  newSetupState(options.Setup),
-		setupSave:              options.Setup.Save,
+		ctx:                         ctx,
+		cwd:                         cwd,
+		swarmDoneAt:                 map[string]time.Time{},
+		userCommands:                loadedUserCommands,
+		composerCursorVisible:       true,
+		userConfigPath:              options.UserConfigPath,
+		doctorUserConfigPath:        doctorUserConfigPath,
+		projectConfigPath:           options.ProjectConfigPath,
+		savedProviders:              options.SavedProviders,
+		gitBranch:                   gitBranch(cwd),
+		providerName:                options.ProviderName,
+		modelName:                   options.ModelName,
+		providerProfile:             options.ProviderProfile,
+		favoriteModels:              favoriteModelSet(options.FavoriteModels),
+		recapsEnabled:               options.RecapsEnabled,
+		provider:                    options.Provider,
+		newProvider:                 options.NewProvider,
+		probeProviderHealth:         options.ProbeProviderHealth,
+		discoverProviderModels:      options.DiscoverProviderModels,
+		discoverOllamaContextWindow: options.DiscoverOllamaContextWindow,
+		registry:                    registry,
+		sessionStore:                sessionStore,
+		sandboxStore:                sandboxStore,
+		mcpConfig:                   options.MCPConfig,
+		mcpPermissionStore:          options.MCPPermissionStore,
+		mcpTokenStore:               options.MCPTokenStore,
+		mcpCommand:                  options.MCPCommand,
+		sandboxSetupCommand:         options.SandboxSetupCommand,
+		agentOptions:                options.AgentOptions,
+		sessionCompactor:            options.SessionCompactor,
+		runtimeMessageSink:          options.RuntimeMessageSink,
+		permissionMode:              permissionMode,
+		reasoningEffort:             options.ReasoningEffort,
+		responseStyle:               defaultedResponseStyle(options.ResponseStyle),
+		themeMode:                   resolveThemeMode(options.Theme, os.Getenv("ZERO_THEME"), options.SavedTheme),
+		hasDarkBg:                   true,
+		userAgent:                   options.UserAgent,
+		usageTracker:                usageTracker,
+		transcript:                  initialTranscript(),
+		transcriptBodyHeights:       newTranscriptBodyHeightCache(defaultTranscriptBodyHeightCacheMaxEntries),
+		prService:                   prService,
+		prState:                     prService.GetState(),
+		input:                       input,
+		spinner:                     runSpinner,
+		now:                         time.Now,
+		notifier:                    notifier,
+		altScreen:                   options.AltScreen,
+		liveUsageCounts:             map[int]int{},
+		swarmSessionMap:             map[string]string{},
+		setup:                       newSetupState(options.Setup),
+		setupSave:                   options.Setup.Save,
 	}
 	// Apply an explicit theme immediately; auto stays on the dark default until
 	// Init's terminal background probe resolves it (see Init / BackgroundColorMsg).
@@ -759,6 +791,18 @@ func composerBlinkCmd() tea.Cmd {
 
 func (m model) Init() tea.Cmd {
 	cmds := []tea.Cmd{textinput.Blink, composerBlinkCmd()}
+	// Bubble Tea documents an initial WindowSizeMsg as delivered automatically
+	// on program start, so m.height/m.width are normally set before the first
+	// render. But that's the terminal proactively pushing a size — if it's
+	// ever missed (a slow/unusual terminal, a multiplexer, a startup race),
+	// nothing else ever asks again: m.height stays its zero value forever,
+	// `if m.altScreen && m.height > 0` (transcriptView) falls back to the
+	// unpadded, non-fullscreen render path for the rest of the session, and
+	// the alt-screen viewport never gets filled below the actual content.
+	// Explicitly requesting it here means Zero doesn't depend solely on the
+	// terminal's unprompted push — mirrors the RequestBackgroundColor request
+	// below for the same reason.
+	cmds = append(cmds, tea.RequestWindowSize)
 	// In auto mode, ask the terminal for its background color; the reply arrives
 	// as tea.BackgroundColorMsg and selects light vs dark (see updateModel).
 	if m.themeMode == themeAuto {
@@ -773,6 +817,13 @@ func (m model) Init() tea.Cmd {
 		if cmd := m.modelPickerProviderDiscoveryCmd(descriptor, m.providerProfile); cmd != nil {
 			cmds = append(cmds, cmd)
 		}
+		// The generic discovery above has no source for a local Ollama model's
+		// context window (see ollamaContextWindowDiscoveryCmd); probe its
+		// native /api/show separately so the gauge works for custom/local
+		// Ollama models too, not just ones in the curated catalog.
+		if cmd := m.ollamaContextWindowDiscoveryCmd(descriptor, m.providerProfile.BaseURL, m.modelName); cmd != nil {
+			cmds = append(cmds, cmd)
+		}
 	}
 	if m.prService != nil && m.runtimeMessageSink != nil {
 		service := m.prService
@@ -849,6 +900,14 @@ func (m model) disarmExitConfirmation() model {
 	return m
 }
 
+func (m model) disarmCancelConfirmation() model {
+	if m.cancelConfirmActive {
+		m.cancelConfirmActive = false
+		m.cancelConfirmSeq++
+	}
+	return m
+}
+
 // Update routes every message through updateModel, then advances the flush
 // frontier for inline rendering. Alt-screen runs keep rows in the managed view
 // instead of printing into terminal scrollback (see flush.go).
@@ -927,6 +986,11 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.exitConfirmActive = false
 		}
 		return m, nil
+	case cancelConfirmExpiredMsg:
+		if msg.seq == m.cancelConfirmSeq {
+			m.cancelConfirmActive = false
+		}
+		return m, nil
 	case dragEdgeScrollTickMsg:
 		if msg.seq != m.edgeScrollSeq || m.edgeScrollDelta == 0 || !m.transcriptSelection.active {
 			return m, nil // stale, or the chain was stopped since this tick was scheduled
@@ -974,6 +1038,13 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 		if !keyCtrl(msg, 'c') {
 			m = m.disarmExitConfirmation()
 		}
+		// Mirrors the exit-confirmation reset above: any key that isn't itself
+		// the confirming Esc means the user moved on to something else, so a
+		// later, unrelated Esc must arm a fresh confirmation rather than
+		// silently cancel off a stale press from seconds ago.
+		if !keyIs(msg, tea.KeyEsc) {
+			m = m.disarmCancelConfirmation()
+		}
 		// The `?` help overlay is modal: `?`, Esc, q, or Enter close it; every
 		// other key is swallowed so nothing types into the hidden composer.
 		if m.helpOverlay {
@@ -996,6 +1067,15 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 			}
 			return m.appendSystemNotice("Mouse interaction re-enabled."), nil
 		case keyIs(msg, tea.KeyEsc):
+			// Esc is heavily overloaded below (subchat exit, MCP cancel, ask-user,
+			// permission deny, wizard/picker/suggestions dismiss, ...) before ever
+			// reaching the run-cancel fallback. Capture whether this press really
+			// is the confirming second Esc BEFORE any of those branches can fire,
+			// then disarm unconditionally: an Esc that gets consumed by one of
+			// them wasn't a confirm, so it must not leave cancelConfirmActive
+			// armed for some later, unrelated Esc to silently act on.
+			wasConfirmingCancel := m.pending && m.cancelConfirmActive
+			m = m.disarmCancelConfirmation()
 			// Subchat view exits on Esc (returns to main chat).
 			if m.subchat.active {
 				m.chatScrollOffset = m.subchat.exit()
@@ -1047,6 +1127,11 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.picker.kind == pickerModel {
 					m.clearModelPickerLoadState()
 				}
+				if m.picker.kind == pickerTheme {
+					// A live theme preview was applied while navigating; restore the
+					// committed palette since Esc dismisses without choosing.
+					m.restoreCommittedTheme()
+				}
 				m.picker = nil
 				return m, nil
 			}
@@ -1056,11 +1141,24 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 			if m.hasQueuedMessage() {
 				return m.clearQueuedMessage(), nil
 			}
-			m.clearComposer()
 			m.clearSuggestions()
 			if m.pending {
-				m.cancelRun()
+				if wasConfirmingCancel {
+					m.clearComposer()
+					m.cancelRun()
+					return m, nil
+				}
+				// First Esc only arms the confirmation — preserve whatever
+				// draft the user has typed, since nothing has actually been
+				// cancelled yet and they may not press Esc again.
+				m.cancelConfirmActive = true
+				m.cancelConfirmSeq++
+				seq := m.cancelConfirmSeq
+				return m, tea.Tick(escCancelConfirmDuration, func(time.Time) tea.Msg {
+					return cancelConfirmExpiredMsg{seq: seq}
+				})
 			}
+			m.clearComposer()
 			return m, nil
 		case keyIs(msg, tea.KeyEnter):
 			if m.transcriptDetailed {
@@ -1181,6 +1279,9 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 					return m, nil
 				}
 				m.picker.deleteQueryRune()
+				// Editing the filter changes which row is highlighted; keep the
+				// theme preview in sync with it (no-op for other pickers).
+				m.previewSelectedTheme()
 				return m, nil
 			}
 			// On an empty composer, Backspace removes the last attachment chip
@@ -1253,7 +1354,7 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.modelPickerIsLoading() {
 					return m, nil
 				}
-				m.picker.move(1)
+				m.pickerMoved(1)
 				return m, nil
 			}
 			if m.suggestionsActive() {
@@ -1295,7 +1396,7 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 				if m.modelPickerIsLoading() {
 					return m, nil
 				}
-				m.picker.move(-1)
+				m.pickerMoved(-1)
 				return m, nil
 			}
 			if m.suggestionsActive() {
@@ -1354,6 +1455,9 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 			}
 			if keyPrintable(msg) {
 				m.picker.appendQuery(keyRunes(msg))
+				// Filtering changes the highlighted row; keep the theme preview in
+				// sync with it (no-op for other pickers).
+				m.previewSelectedTheme()
 			}
 			return m, nil
 		}
@@ -1610,6 +1714,7 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 		}
 		m.clearStreamingToolCall() // active run finished — drop any lingering "writing" block
 		m.pending = false
+		m = m.disarmCancelConfirmation() // the run finished on its own — nothing left to confirm cancelling
 		// Fully reset the fade state at stream end. The next render
 		// emits the final row in solid ink (no settling animation), and
 		// the pending streamingFadeTickMsg that lands after this point
@@ -1911,6 +2016,14 @@ func (m model) updateModel(msg tea.Msg) (tea.Model, tea.Cmd) {
 		return m.applySetupOAuthDeviceCode(msg)
 	case modelPickerModelsDiscoveredMsg:
 		return m.applyModelPickerModelsDiscovered(msg), nil
+	case ollamaContextWindowDiscoveredMsg:
+		if msg.err == nil && msg.contextWindow > 0 {
+			if m.ollamaContextWindowByModel == nil {
+				m.ollamaContextWindowByModel = map[string]int{}
+			}
+			m.ollamaContextWindowByModel[msg.modelName] = msg.contextWindow
+		}
+		return m, nil
 	case mcpCommandResultMsg:
 		return m.applyMCPCommandResultMessage(msg), nil
 	}
@@ -1934,6 +2047,17 @@ func (m model) View() tea.View {
 
 	view := tea.NewView(content)
 	view.AltScreen = m.altScreen
+	// Paint the whole frame with the active theme's surface. Zero never paints the
+	// terminal's own canvas, so without this a theme's text falls on the terminal
+	// background — fine when they share polarity, but a light theme's dark text on a
+	// dark terminal (or vice versa) is invisible, and a color theme never shows its
+	// real surface. Painting the panel makes every theme self-contained and legible
+	// on any terminal, and fills the transparent popup interiors (e.g. the /theme
+	// picker) too. Alt-screen only, so inline output never leaves a painted
+	// background behind in the user's scrollback after exit.
+	if m.altScreen {
+		view.BackgroundColor = zeroTheme.bgPanel
+	}
 	view.ReportFocus = m.notifier != nil
 	if m.wantsMouseCapture() {
 		// AllMotion (not CellMotion) is required for hover highlighting: it
@@ -2695,6 +2819,15 @@ const quietWorkingHint = 8 * time.Second
 // quietGenerationHint returns a "still generating…" cue with an advancing
 // quiet-timer when the active turn has produced no streamed output for a while,
 // else "". The advancing number is itself the liveness signal.
+//
+// Past half the provider's idle timeout, the cue escalates to name what's
+// actually happening and when Zero will act on its own: a heartbeating-but-
+// silent stream (observed on chatgpt/gpt-5.x and ollama reasoning models,
+// see providerio.ErrStreamStalled) is bounded by the content-stall watchdog at
+// idleTimeout × providerio.StreamContentStallFactor, but until it fires this
+// exact same plain "still generating… Xs" text is indistinguishable from a
+// genuine hang — the ticking number was the only signal, and it looks
+// identical whether real (if slow) content is coming or nothing ever will.
 func (m model) quietGenerationHint() string {
 	if m.activeRunID == 0 {
 		return ""
@@ -2710,6 +2843,10 @@ func (m model) quietGenerationHint() string {
 	if quiet < quietWorkingHint {
 		return ""
 	}
+	if idleTimeout := providerio.ResolveStreamIdleTimeout(0); idleTimeout > 0 && quiet >= idleTimeout/2 {
+		ceiling := idleTimeout * providerio.StreamContentStallFactor
+		return fmt.Sprintf("still generating… %s — unusually quiet, Zero will auto-recover by ~%s if it doesn't resume", formatWorkingElapsed(quiet), formatWorkingElapsed(ceiling))
+	}
 	return "still generating… " + formatWorkingElapsed(quiet)
 }
 
@@ -3265,14 +3402,20 @@ func (m model) choosePicker() (tea.Model, tea.Cmd) {
 	}
 	item, ok := picker.current()
 	if !ok {
+		if picker.kind == pickerTheme {
+			// No selectable row (e.g. the filter matched nothing): undo any live
+			// preview so the palette matches the committed m.themeMode.
+			m.restoreCommittedTheme()
+		}
 		return m, nil
 	}
+	var cmd tea.Cmd
 	switch picker.kind {
 	case pickerModel:
 		text := ""
 		if owner := strings.TrimSpace(item.OwnerProvider); owner != "" && !strings.EqualFold(owner, strings.TrimSpace(m.providerName)) {
 			// A model from another saved provider: switch provider + model together.
-			m, text = m.switchProviderModel(owner, item.Value)
+			m, text, cmd = m.switchProviderModel(owner, item.Value)
 		} else {
 			m, text = m.handleModelCommand(item.Value)
 		}
@@ -3289,8 +3432,20 @@ func (m model) choosePicker() (tea.Model, tea.Cmd) {
 		if text != "" {
 			m.transcript = reduceTranscript(m.transcript, transcriptAction{kind: actionAppendSystem, text: text})
 		}
+	case pickerTheme:
+		// The hovered palette is already live from the preview; handleThemeCommand
+		// records the choice (m.themeMode) and re-applies it, and reports the switch.
+		text := ""
+		m, text = m.handleThemeCommand(item.Value)
+		m.transcript = reduceTranscript(m.transcript, transcriptAction{kind: actionAppendSystem, text: text})
+		if m.themeMode == themeAuto {
+			// Re-probe the terminal background so a committed `auto` re-detects
+			// light/dark instead of reusing the preview's reading — mirrors the
+			// text /theme dispatch (M17).
+			return m, tea.RequestBackgroundColor
+		}
 	}
-	return m, nil
+	return m, cmd
 }
 
 func (m model) chooseSuggestion() (tea.Model, tea.Cmd) {
@@ -3544,6 +3699,13 @@ func (m model) handleSubmit() (tea.Model, tea.Cmd) {
 		m.transcript = reduceTranscript(m.transcript, transcriptAction{kind: actionAppendSystem, text: text})
 		return m, nil
 	case commandTheme:
+		// Bare `/theme` opens the popup picker (live preview on move, apply on
+		// Enter), matching /model and /effort. An explicit `/theme auto|dark|light`
+		// (or `/theme list`) still runs the text handler directly.
+		if strings.TrimSpace(command.text) == "" {
+			m.picker = m.newThemePicker()
+			return m, nil
+		}
 		text := ""
 		m, text = m.handleThemeCommand(command.text)
 		m.transcript = reduceTranscript(m.transcript, transcriptAction{kind: actionAppendSystem, text: text})
@@ -3807,7 +3969,8 @@ func (m *model) cancelRun() {
 	m.pending = false
 	m.runCancel = nil
 	m.activeRunID = 0
-	m.plan.frozenAt = m.now() // freeze the plan clock while idle (no run in flight)
+	m.cancelConfirmActive = false // whatever path got here, there's nothing left to confirm cancelling
+	m.plan.frozenAt = m.now()     // freeze the plan clock while idle (no run in flight)
 	m.pendingPermission = nil
 	m.pendingAskUser = nil
 	// The interim block renders streamingText live; a cancelled run's partial

internal/tui/model_catalog.go

@@ -84,6 +84,13 @@ func (m model) modelContextWindow(modelName string) int {
 			return window
 		}
 	}
+	// A custom/local Ollama model tag has no curated-catalog entry, and its
+	// OpenAI-compatible /v1/models listing (the discoveredContextWindow source
+	// above) doesn't carry context-window metadata at all — see
+	// ollamaContextWindowDiscoveryCmd, the only other source for this.
+	if window := m.ollamaContextWindowByModel[trimmed]; window > 0 {
+		return window
+	}
 	// Unknown: report 0 so display gauges show no denominator. Compaction enablement
 	// applies its own positive fallback via modelregistry.AgentContextWindow.
 	return 0

internal/tui/model_test.go

@@ -1108,7 +1108,87 @@ func TestPromptSubmitDoesNotStartAnotherRunWhilePending(t *testing.T) {
 	}
 }
 
-func TestEscCancelsPendingRun(t *testing.T) {
+func TestEscRequiresSecondPressToCancelPendingRun(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+	cancelled := false
+	m.pending = true
+	m.activeRunID = 1
+	m.runCancel = func() { cancelled = true }
+
+	updated, cmd := m.Update(testKey(tea.KeyEsc))
+	next := updated.(model)
+
+	if cancelled {
+		t.Fatal("first Esc should not cancel the pending run")
+	}
+	if !next.pending {
+		t.Fatal("first Esc should leave the run pending")
+	}
+	if !next.cancelConfirmActive {
+		t.Fatal("first Esc should arm cancel confirmation")
+	}
+	if cmd == nil {
+		t.Fatal("first Esc should schedule confirmation expiry")
+	}
+	status := plainRender(t, next.statusLine(80))
+	if !strings.Contains(status, escCancelConfirmText) {
+		t.Fatalf("status line = %q, want cancel confirmation", status)
+	}
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+
+	if !cancelled {
+		t.Fatal("second Esc should cancel pending run")
+	}
+	if next.pending {
+		t.Fatal("expected second Esc to clear pending state")
+	}
+	if next.activeRunID != 0 || next.runCancel != nil {
+		t.Fatalf("expected active run state to clear, got id=%d cancel=%v", next.activeRunID, next.runCancel)
+	}
+	if next.cancelConfirmActive {
+		t.Fatal("cancelling should clear cancel confirmation")
+	}
+}
+
+// TestEscArmingCancelConfirmationPreservesComposerDraft: the first Esc only
+// arms the confirmation — nothing has actually been cancelled yet, so it
+// must not destroy a draft the user is still typing. Only the confirming
+// second Esc (the one that actually cancels the run) clears the composer.
+func TestEscArmingCancelConfirmationPreservesComposerDraft(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+	m.pending = true
+	m.activeRunID = 1
+	m.runCancel = func() {}
+	m.input.SetValue("draft prompt")
+
+	updated, _ := m.Update(testKey(tea.KeyEsc))
+	next := updated.(model)
+
+	if !next.cancelConfirmActive {
+		t.Fatal("first Esc should arm cancel confirmation")
+	}
+	if next.composerValue() != "draft prompt" {
+		t.Fatalf("first Esc should preserve the draft, got %q", next.composerValue())
+	}
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+
+	if next.pending {
+		t.Fatal("second Esc should cancel the pending run")
+	}
+	if next.composerValue() != "" {
+		t.Fatalf("the confirming second Esc should clear the draft, got %q", next.composerValue())
+	}
+}
+
+// TestPasteDisarmsCancelConfirmation: a paste isn't a keypress, so it never
+// went through the generic "any non-Esc key disarms it" hook. Pasting is a
+// deliberate action just like typing or clicking — it must disarm a stale
+// confirmation too, or a later, unrelated Esc could silently cancel the run.
+func TestPasteDisarmsCancelConfirmation(t *testing.T) {
 	m := newModel(context.Background(), Options{})
 	cancelled := false
 	m.pending = true
@@ -1117,15 +1197,131 @@ func TestEscCancelsPendingRun(t *testing.T) {
 
 	updated, _ := m.Update(testKey(tea.KeyEsc))
 	next := updated.(model)
+	if !next.cancelConfirmActive {
+		t.Fatal("first Esc should arm cancel confirmation")
+	}
 
-	if !cancelled {
-		t.Fatal("expected Esc to cancel pending run")
+	updated, _ = next.Update(testPaste("pasted text"))
+	next = updated.(model)
+	if next.cancelConfirmActive {
+		t.Fatal("a paste should disarm the stale cancel confirmation")
 	}
-	if next.pending {
-		t.Fatal("expected Esc to clear pending state")
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+	if cancelled {
+		t.Fatal("Esc after a paste should re-arm, not immediately cancel")
 	}
-	if next.activeRunID != 0 || next.runCancel != nil {
-		t.Fatalf("expected active run state to clear, got id=%d cancel=%v", next.activeRunID, next.runCancel)
+	if !next.cancelConfirmActive {
+		t.Fatal("Esc after a paste should arm a fresh confirmation")
+	}
+}
+
+func TestEscCancelConfirmationExpires(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+	m.pending = true
+	m.activeRunID = 1
+	m.runCancel = func() {}
+
+	updated, _ := m.Update(testKey(tea.KeyEsc))
+	next := updated.(model)
+	seq := next.cancelConfirmSeq
+
+	updated, _ = next.Update(cancelConfirmExpiredMsg{seq: seq - 1})
+	next = updated.(model)
+	if !next.cancelConfirmActive {
+		t.Fatal("stale expiry should not clear active cancel confirmation")
+	}
+
+	updated, _ = next.Update(cancelConfirmExpiredMsg{seq: seq})
+	next = updated.(model)
+	if next.cancelConfirmActive {
+		t.Fatal("matching expiry should clear cancel confirmation")
+	}
+	if !next.pending {
+		t.Fatal("expiring the confirmation should not cancel the run")
+	}
+}
+
+// TestEscCancelConfirmationDisarmsOnInterveningKey mirrors
+// TestCtrlCExitConfirmationDisarmsOnInterveningKey: an intervening key other
+// than Esc (typing, Ctrl+O, etc.) means the user moved on to something else,
+// so a later, unrelated Esc must arm a fresh confirmation instead of
+// silently cancelling off a stale press from seconds ago.
+func TestEscCancelConfirmationDisarmsOnInterveningKey(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+	cancelled := false
+	m.pending = true
+	m.activeRunID = 1
+	m.runCancel = func() { cancelled = true }
+
+	updated, _ := m.Update(testKey(tea.KeyEsc))
+	next := updated.(model)
+	if !next.cancelConfirmActive {
+		t.Fatal("first Esc should arm cancel confirmation")
+	}
+	seq := next.cancelConfirmSeq
+
+	updated, _ = next.Update(testKey('h'))
+	next = updated.(model)
+	if next.cancelConfirmActive {
+		t.Fatal("an intervening non-Esc key should disarm cancel confirmation")
+	}
+	if next.cancelConfirmSeq == seq {
+		t.Fatal("disarming should advance the sequence so a stale expiry tick is ignored")
+	}
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+	if cancelled {
+		t.Fatal("Esc after an intervening key should re-arm, not cancel")
+	}
+	if !next.cancelConfirmActive {
+		t.Fatal("Esc after an intervening key should arm a fresh confirmation")
+	}
+}
+
+// TestEscCancelConfirmationDisarmsWhenStolenByAskUser: a mid-turn ask_user
+// prompt lands between the two Esc presses. The user's second Esc denies the
+// questionnaire (an earlier branch in the Esc handler), not a confirm, so it
+// must not leave cancelConfirmActive armed for a later, unrelated Esc to
+// silently cancel the run.
+func TestEscCancelConfirmationDisarmsWhenStolenByAskUser(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+	cancelled := false
+	m.pending = true
+	m.activeRunID = 1
+	m.runCancel = func() { cancelled = true }
+
+	updated, _ := m.Update(testKey(tea.KeyEsc))
+	next := updated.(model)
+	if !next.cancelConfirmActive {
+		t.Fatal("first Esc should arm cancel confirmation")
+	}
+
+	request := agent.AskUserRequest{Questions: []agent.AskUserQuestion{{Question: "name?"}}}
+	next.pendingAskUser = &pendingAskUserPrompt{
+		request: request,
+		answer:  func([]string) {},
+		states:  newAskUserStates(request.Questions),
+	}
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+	if cancelled {
+		t.Fatal("an Esc consumed by the ask-user prompt must not cancel the run")
+	}
+	if next.cancelConfirmActive {
+		t.Fatal("an Esc consumed by the ask-user prompt must disarm the stale cancel confirmation")
+	}
+
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
+	if cancelled {
+		t.Fatal("the next Esc should arm a fresh confirmation, not immediately cancel")
+	}
+	if !next.cancelConfirmActive {
+		t.Fatal("the next Esc should arm a fresh confirmation")
 	}
 }
 

internal/tui/mouse.go

@@ -40,6 +40,15 @@ func (m model) handleMouse(msg tea.MouseMsg) (tea.Model, tea.Cmd) {
 	if m.providerWizard != nil && m.providerWizard.oauthPending {
 		return m, nil
 	}
+	// A click is a deliberate action, same as a keypress — it means the user
+	// moved on to something else, so it disarms a stale Esc cancel-confirmation
+	// rather than leaving it armed for some later, unrelated Esc to act on.
+	// Scoped to actual clicks (not hover/motion/wheel), since motion events fire
+	// continuously while the mouse merely sits over the terminal and would
+	// otherwise defeat the confirmation window on every render tick.
+	if mouseLeftPress(msg) || mouseRightPress(msg) {
+		m = m.disarmCancelConfirmation()
+	}
 	// A right-click pastes the clipboard straight into the focused field — no
 	// menu. pasteFromClipboardCmd reads the clipboard off the Update goroutine; the
 	// clipboardReadMsg result is routed by routePaste to wherever input is focused
@@ -130,7 +139,7 @@ func (m model) handleMouse(msg tea.MouseMsg) (tea.Model, tea.Cmd) {
 			if m.modelPickerIsLoading() {
 				return m, nil
 			}
-			m.picker.move(-1)
+			m.pickerMoved(-1)
 			return m, nil
 		}
 		if m.suggestionsActive() {
@@ -162,7 +171,7 @@ func (m model) handleMouse(msg tea.MouseMsg) (tea.Model, tea.Cmd) {
 			if m.modelPickerIsLoading() {
 				return m, nil
 			}
-			m.picker.move(1)
+			m.pickerMoved(1)
 			return m, nil
 		}
 		if m.suggestionsActive() {
@@ -441,6 +450,9 @@ func (m *model) selectGenericPickerAtMouse(msg tea.MouseMsg) (mouseSelectionTarg
 		if hit.y == line {
 			index := start + offset
 			m.picker.selected = index
+			// Clicking (or hovering onto) a row live-previews it, like arrow keys,
+			// so the theme picker repaints before the confirming second click.
+			m.previewSelectedTheme()
 			return mouseSelectionTarget{Scope: "picker", Kind: int(m.picker.kind), Value: item.Value, Index: index}, true
 		}
 		line++

internal/tui/oauth_device.go

@@ -44,6 +44,9 @@ func oauthDevicePrepare(name string) (oauth.DeviceAuth, oauth.Config, error) {
 		Store:       store,
 		HTTPClient:  &http.Client{Timeout: 60 * time.Second},
 		OpenBrowser: browser.OpenURL,
+		// Device-flow providers (e.g. Hugging Face) rely on the baked-in preset for
+		// their endpoints; opt in so the device code can be requested.
+		AllowPresets: true,
 	})
 	if err != nil {
 		return oauth.DeviceAuth{}, oauth.Config{}, err
@@ -62,8 +65,9 @@ func oauthDeviceComplete(name string, cfg oauth.Config, auth oauth.DeviceAuth) e
 		return err
 	}
 	manager, err := oauth.NewManager(oauth.ManagerOptions{
-		Store:      store,
-		HTTPClient: &http.Client{Timeout: 60 * time.Second},
+		Store:        store,
+		HTTPClient:   &http.Client{Timeout: 60 * time.Second},
+		AllowPresets: true, // preset config is needed to poll/exchange the device token
 	})
 	if err != nil {
 		return err
@@ -84,8 +88,9 @@ func oauthStoredToken(ctx context.Context, providerID string) string {
 		return ""
 	}
 	manager, err := oauth.NewManager(oauth.ManagerOptions{
-		Store:      store,
-		HTTPClient: &http.Client{Timeout: 30 * time.Second},
+		Store:        store,
+		HTTPClient:   &http.Client{Timeout: 30 * time.Second},
+		AllowPresets: true, // refreshing a preset-provider token re-resolves its config
 	})
 	if err != nil {
 		return ""

internal/tui/options.go

@@ -20,41 +20,46 @@ import (
 
 // Options configures the reusable Zero terminal UI shell.
 type Options struct {
-	Cwd                    string
-	UserConfigPath         string
-	DoctorUserConfigPath   string
-	ProjectConfigPath      string
-	ProviderName           string
-	ModelName              string
-	ProviderProfile        config.ProviderProfile
-	SavedProviders         []config.ProviderProfile // all configured providers, for the /model multi-provider list
-	FavoriteModels         []string
-	RecapsEnabled          bool
-	Provider               zeroruntime.Provider
-	NewProvider            func(config.ProviderProfile) (zeroruntime.Provider, error)
-	ProbeProviderHealth    func(context.Context, providerhealth.Options) providerhealth.Result
-	DiscoverProviderModels func(context.Context, config.ProviderProfile) ([]providermodeldiscovery.Model, error)
-	RuntimeMessageSink     func(tea.Msg)
-	Registry               *tools.Registry
-	SessionStore           *sessions.Store
-	SandboxStore           *sandbox.GrantStore
-	MCPConfig              config.MCPConfig
-	MCPPermissionStore     *mcp.PermissionStore
-	MCPTokenStore          *mcp.TokenStore
-	MCPCommand             func(context.Context, []string) MCPCommandResult
-	SandboxSetupCommand    func(context.Context) SandboxSetupCommandResult
-	UsageTracker           *usage.Tracker
-	SessionCompactor       SessionCompactor
-	PrService              *PrService
+	Cwd                         string
+	UserConfigPath              string
+	DoctorUserConfigPath        string
+	ProjectConfigPath           string
+	ProviderName                string
+	ModelName                   string
+	ProviderProfile             config.ProviderProfile
+	SavedProviders              []config.ProviderProfile // all configured providers, for the /model multi-provider list
+	FavoriteModels              []string
+	RecapsEnabled               bool
+	Provider                    zeroruntime.Provider
+	NewProvider                 func(config.ProviderProfile) (zeroruntime.Provider, error)
+	ProbeProviderHealth         func(context.Context, providerhealth.Options) providerhealth.Result
+	DiscoverProviderModels      func(context.Context, config.ProviderProfile) ([]providermodeldiscovery.Model, error)
+	DiscoverOllamaContextWindow func(ctx context.Context, baseURL string, model string) (int, error)
+	RuntimeMessageSink          func(tea.Msg)
+	Registry                    *tools.Registry
+	SessionStore                *sessions.Store
+	SandboxStore                *sandbox.GrantStore
+	MCPConfig                   config.MCPConfig
+	MCPPermissionStore          *mcp.PermissionStore
+	MCPTokenStore               *mcp.TokenStore
+	MCPCommand                  func(context.Context, []string) MCPCommandResult
+	SandboxSetupCommand         func(context.Context) SandboxSetupCommandResult
+	UsageTracker                *usage.Tracker
+	SessionCompactor            SessionCompactor
+	PrService                   *PrService
 
 	AgentOptions    agent.Options
 	PermissionMode  agent.PermissionMode
 	ReasoningEffort modelregistry.ReasoningEffort
 	ResponseStyle   string
-	// Theme is the operator's palette preference: "auto" (default), "dark", or
-	// "light". Set from the --theme flag; falls back to ZERO_THEME then auto.
-	Theme     string
-	UserAgent string
+	// Theme is the operator's palette preference: "auto" (default), a built-in
+	// ("dark"/"light"), or a registered color theme. Set from the --theme flag;
+	// falls back to ZERO_THEME, then the persisted SavedTheme, then auto.
+	Theme string
+	// SavedTheme is the theme persisted in user config (Preferences.Theme). Applied
+	// at startup below --theme and ZERO_THEME, so a /theme choice survives restart.
+	SavedTheme string
+	UserAgent  string
 
 	// Notify configures completion / awaiting-input notifications.
 	Notify config.NotifyConfig

internal/tui/picker.go

@@ -23,6 +23,7 @@ const (
 	pickerModel pickerKind = iota
 	pickerEffort
 	pickerSession
+	pickerTheme
 )
 
 // pickerItem is one selectable row: Label is shown, Value is passed to the
@@ -564,6 +565,46 @@ type modelPickerModelsDiscoveredMsg struct {
 	err        error
 }
 
+// ollamaContextWindowDiscoveredMsg carries the result of an async /api/show
+// probe against a local Ollama daemon (see ollamaContextWindowDiscoveryCmd).
+// A zero contextWindow (or a non-nil err) means the probe found nothing
+// usable and the map is left untouched, not zeroed out.
+type ollamaContextWindowDiscoveredMsg struct {
+	modelName     string
+	contextWindow int
+	err           error
+}
+
+// ollamaContextWindowDiscoveryCmd probes a local Ollama daemon's native
+// /api/show endpoint for modelName's context length. Scoped to the local
+// Ollama provider only (catalog ID "ollama", not "ollama-cloud" — a
+// different hosted service this endpoint isn't assumed to exist on): the
+// generic /v1/models discovery has no source for this metadata for
+// custom/local model tags, so without this the context gauge just never
+// shows for them (see modelContextWindow).
+func (m model) ollamaContextWindowDiscoveryCmd(descriptor providercatalog.Descriptor, baseURL string, modelName string) tea.Cmd {
+	if descriptor.ID != "ollama" {
+		return nil
+	}
+	modelName = strings.TrimSpace(modelName)
+	baseURL = strings.TrimSpace(baseURL)
+	if modelName == "" || baseURL == "" {
+		return nil
+	}
+	discover := m.discoverOllamaContextWindow
+	if discover == nil {
+		discover = func(ctx context.Context, baseURL string, model string) (int, error) {
+			return providermodeldiscovery.DiscoverOllamaContextWindow(ctx, baseURL, model, providermodeldiscovery.Options{})
+		}
+	}
+	return func() tea.Msg {
+		ctx, cancel := context.WithTimeout(m.ctx, 8*time.Second)
+		defer cancel()
+		window, err := discover(ctx, baseURL, modelName)
+		return ollamaContextWindowDiscoveredMsg{modelName: modelName, contextWindow: window, err: err}
+	}
+}
+
 func (m model) normalizeProfileForProvider(provider providercatalog.Descriptor) config.ProviderProfile {
 	profile := m.providerProfile
 	normalizeIdentity := profileMatchesProviderBaseURL(profile, provider) ||
@@ -726,3 +767,44 @@ func (m model) newEffortPicker() *commandPicker {
 	}
 	return &commandPicker{kind: pickerEffort, title: "select reasoning effort", items: items, selected: selected}
 }
+
+// newThemePicker lists `auto` plus every registered theme as a popup, grouped into
+// Dark/Light sections (the registry is ordered dark-then-light so the group header
+// changes exactly once), preselecting the active preference. Bare `/theme` opens the
+// same overlay /model and /effort use. Moving the cursor live-previews each palette
+// (previewSelectedTheme); Enter commits the highlighted theme (choosePicker) and Esc
+// restores the previous one (Update's picker-cancel path). Items stay 1:1 with
+// themeModes and in the same order, so the popup and /theme state list agree.
+func (m model) newThemePicker() *commandPicker {
+	items := make([]pickerItem, 0, len(themeModes))
+	selected := 0
+	// `auto` sits at the top with an empty Group, so it renders header-less above
+	// the Dark/Light sections.
+	items = append(items, pickerItem{Label: string(themeAuto), Value: string(themeAuto), Meta: "match terminal"})
+	for _, entry := range themeRegistry {
+		group := "Light"
+		if entry.IsDark {
+			group = "Dark"
+		}
+		items = append(items, pickerItem{Group: group, Label: entry.Label, Value: entry.Name})
+		if entry.Name == string(m.themeMode) {
+			selected = len(items) - 1
+		}
+	}
+	// allItems lets the query filter restore rows on Backspace (one-way narrowing
+	// otherwise, since applyQuery falls back to the current items without it).
+	return &commandPicker{kind: pickerTheme, title: "select theme", items: items, allItems: append([]pickerItem{}, items...), selected: selected}
+}
+
+// pickerMoved advances the open picker's cursor by delta and live-previews the new
+// selection where the picker supports it — stepping through the /theme popup
+// repaints the UI in the hovered palette. Safe to call with no picker open. Callers
+// mutate through m.picker (a pointer) and the global theme, so the value receiver
+// is fine.
+func (m model) pickerMoved(delta int) {
+	if m.picker == nil {
+		return
+	}
+	m.picker.move(delta)
+	m.previewSelectedTheme()
+}

internal/tui/picker_test.go

@@ -14,6 +14,7 @@ import (
 
 	"github.com/Gitlawb/zero/internal/config"
 	"github.com/Gitlawb/zero/internal/modelregistry"
+	"github.com/Gitlawb/zero/internal/providercatalog"
 	"github.com/Gitlawb/zero/internal/providermodeldiscovery"
 	"github.com/Gitlawb/zero/internal/zeroruntime"
 )
@@ -639,14 +640,17 @@ func TestEffortPickerOpensForSupportedModel(t *testing.T) {
 	}
 }
 
-func TestThemeCommandOpensNoPicker(t *testing.T) {
-	// /theme keeps the existing shell-only message; no picker opens.
+func TestThemeCommandOpensPicker(t *testing.T) {
+	// Bare /theme opens the theme popup (live preview on move, apply on Enter),
+	// like /model and /effort. Full preview/commit/cancel behavior is covered in
+	// theme_picker_test.go; here we just pin that the no-arg command opens it.
+	defer applyTheme(themeDark, true)
 	m := newModel(context.Background(), Options{})
 	m.input.SetValue("/theme")
 	updated, _ := m.Update(testKey(tea.KeyEnter))
 	m = updated.(model)
-	if m.picker != nil {
-		t.Fatal("/theme should not open a picker")
+	if m.picker == nil || m.picker.kind != pickerTheme {
+		t.Fatalf("expected the theme picker to open, got %#v", m.picker)
 	}
 }
 
@@ -875,4 +879,100 @@ func TestModelContextWindowResolution(t *testing.T) {
 	if got := m.modelContextWindow(""); got != 0 {
 		t.Fatalf("empty model name should yield 0, got %d", got)
 	}
+	// A custom/local Ollama model tag has no curated-catalog entry and its
+	// generic /v1/models listing carries no window either — the only source is
+	// the Ollama-specific /api/show probe, landed via ollamaContextWindowByModel.
+	m.ollamaContextWindowByModel = map[string]int{"kimi-k2.7-code:cloud": 131072}
+	if got := m.modelContextWindow("kimi-k2.7-code:cloud"); got != 131072 {
+		t.Fatalf("ollama-discovered window should be used for an unregistered model, got %d", got)
+	}
+}
+
+// TestOllamaContextWindowDiscoveryCmdScopedToLocalOllama: the /api/show probe
+// only makes sense against a local Ollama daemon (catalog ID "ollama") — a
+// different provider like "ollama-cloud" is a distinct hosted service this
+// endpoint isn't assumed to exist on, and every other provider already has
+// its context window covered by the curated catalog or /v1/models discovery.
+func TestOllamaContextWindowDiscoveryCmdScopedToLocalOllama(t *testing.T) {
+	m := model{ctx: context.Background()}
+
+	ollama, ok := providercatalog.Get("ollama")
+	if !ok {
+		t.Fatal("expected \"ollama\" to be a registered catalog descriptor")
+	}
+	if cmd := m.ollamaContextWindowDiscoveryCmd(ollama, "http://localhost:11434/v1", "kimi-k2.7-code:cloud"); cmd == nil {
+		t.Fatal("expected a discovery command for the local ollama provider")
+	}
+
+	ollamaCloud, ok := providercatalog.Get("ollama-cloud")
+	if !ok {
+		t.Fatal("expected \"ollama-cloud\" to be a registered catalog descriptor")
+	}
+	if cmd := m.ollamaContextWindowDiscoveryCmd(ollamaCloud, "https://ollama.com/v1", "qwen3-coder:480b"); cmd != nil {
+		t.Fatal("ollama-cloud is a different hosted service; must not probe /api/show against it")
+	}
+
+	if cmd := m.ollamaContextWindowDiscoveryCmd(ollama, "", "kimi-k2.7-code:cloud"); cmd != nil {
+		t.Fatal("an empty base URL should yield no command")
+	}
+	if cmd := m.ollamaContextWindowDiscoveryCmd(ollama, "http://localhost:11434/v1", ""); cmd != nil {
+		t.Fatal("an empty model name should yield no command")
+	}
+}
+
+// TestOllamaContextWindowDiscoveredMsgPopulatesMap verifies the Update()
+// handler for the async probe's result actually reaches modelContextWindow's
+// fallback source, and that a failed/zero probe leaves the map untouched
+// rather than caching a bogus zero.
+func TestOllamaContextWindowDiscoveredMsgPopulatesMap(t *testing.T) {
+	m := newModel(context.Background(), Options{})
+
+	updated, cmd := m.Update(ollamaContextWindowDiscoveredMsg{modelName: "kimi-k2.7-code:cloud", contextWindow: 131072})
+	next := updated.(model)
+	if cmd != nil {
+		t.Fatal("applying a discovered window should not schedule further work")
+	}
+	if got := next.modelContextWindow("kimi-k2.7-code:cloud"); got != 131072 {
+		t.Fatalf("modelContextWindow after discovery = %d, want 131072", got)
+	}
+
+	updated, _ = next.Update(ollamaContextWindowDiscoveredMsg{modelName: "other-model", contextWindow: 0, err: errors.New("boom")})
+	next = updated.(model)
+	if got := next.modelContextWindow("other-model"); got != 0 {
+		t.Fatalf("a failed probe must not populate a window, got %d", got)
+	}
+}
+
+// TestSwitchProviderModelWarmsDiscoveryForTheNewProvider: switching providers
+// mid-session (e.g. via the /model picker) previously fired no discovery at
+// all for the newly active provider — Init() only warms the provider active
+// at launch — so the context gauge stayed blank for the rest of the session
+// unless /model happened to be reopened separately. Switching to Ollama
+// specifically must also warm the /api/show probe, the only source of a
+// context window for custom/local Ollama models.
+func TestSwitchProviderModelWarmsDiscoveryForTheNewProvider(t *testing.T) {
+	m := newModel(context.Background(), Options{
+		ProviderName:    "openai",
+		ModelName:       "gpt-5.1",
+		Provider:        &fakeProvider{},
+		ProviderProfile: config.ProviderProfile{Name: "openai", CatalogID: "openai", Model: "gpt-5.1"},
+		SavedProviders: []config.ProviderProfile{
+			{Name: "openai", CatalogID: "openai", Model: "gpt-5.1"},
+			{Name: "ollama", CatalogID: "ollama", ProviderKind: config.ProviderKindOpenAICompatible, BaseURL: "http://localhost:11434/v1", Model: "kimi-k2.7-code:cloud"},
+		},
+		NewProvider: func(config.ProviderProfile) (zeroruntime.Provider, error) {
+			return &fakeProvider{}, nil
+		},
+	})
+
+	next, text, cmd := m.switchProviderModel("ollama", "kimi-k2.7-code:cloud")
+	if !strings.Contains(text, "Switched to ollama") {
+		t.Fatalf("switch notice = %q, want it to confirm the switch", text)
+	}
+	if next.modelName != "kimi-k2.7-code:cloud" || next.providerName != "ollama" {
+		t.Fatalf("model/provider not switched: modelName=%q providerName=%q", next.modelName, next.providerName)
+	}
+	if cmd == nil {
+		t.Fatal("switching to ollama should warm both the generic and ollama-specific discovery commands")
+	}
 }

internal/tui/provider_wizard.go

@@ -166,6 +166,10 @@ func runProviderTokenLogin(name string) error {
 		Store:       store,
 		HTTPClient:  &http.Client{Timeout: 60 * time.Second},
 		OpenBrowser: browser.OpenURL,
+		// The user explicitly chose to sign in with this provider's OAuth, so opt
+		// into its baked-in preset (e.g. xAI's public client_id); without this the
+		// config never resolves and the browser never opens.
+		AllowPresets: true,
 	})
 	if err != nil {
 		return err
@@ -1229,9 +1233,29 @@ func (wizard *providerWizardState) renderProviderStep(width int) []string {
 	for offset, provider := range wizard.providers[start : start+maxVisible] {
 		lines = append(lines, wizard.renderSelectableProvider(width, start+offset, provider))
 	}
+	// A failed OAuth attempt leaves the wizard on this list (it does not advance),
+	// so the error must render here or the click looks like a silent no-op. The
+	// credential step renders its own copy for the ctrl+o path.
+	if wizard.oauthMode && wizard.oauthErr != "" {
+		lines = append(lines, "", zeroTheme.red.Render("OAuth login failed: "+wizard.oauthErr))
+		if hint := providerWizardOAuthErrHint(wizard.currentProvider()); hint != "" {
+			lines = append(lines, zeroTheme.faint.Render(hint))
+		}
+	}
 	return lines
 }
 
+// providerWizardOAuthErrHint returns a provider-specific next step for a failed
+// OAuth login. Hugging Face ships no public client_id (unlike xAI), so a login
+// can only work once the operator registers an app and supplies its client_id.
+func providerWizardOAuthErrHint(provider providercatalog.Descriptor) string {
+	if strings.EqualFold(provider.ID, "huggingface") {
+		return "Hugging Face needs your own app: create one at " +
+			"https://huggingface.co/settings/applications/new, then set ZERO_OAUTH_HUGGINGFACE_CLIENT_ID."
+	}
+	return ""
+}
+
 func (wizard *providerWizardState) renderSelectableProvider(width int, index int, provider providercatalog.Descriptor) string {
 	selected := index == wizard.selectedProvider
 	surface := transparentSurface

internal/tui/provider_wizard_oauth_test.go

@@ -125,6 +125,36 @@ func TestProviderWizardDeviceCodeMsgShowsCodeAndPolls(t *testing.T) {
 	}
 }
 
+// A failed OAuth attempt leaves the wizard on the provider list; the error must be
+// rendered there (not just on the credential step) so a click isn't a silent
+// no-op, and Hugging Face gets an actionable client_id hint.
+func TestProviderStepSurfacesOAuthError(t *testing.T) {
+	m := mouseTestModel()
+	m.providerWizard = m.newProviderWizard()
+	wizard := m.providerWizard
+	wizard.oauthMode = true
+	wizard.providers = providerWizardOAuthDescriptors()
+	found := false
+	for i, p := range wizard.providers {
+		if strings.EqualFold(p.ID, "huggingface") {
+			wizard.selectedProvider = i
+			found = true
+		}
+	}
+	if !found {
+		t.Fatal("huggingface should be an OAuth-capable provider")
+	}
+	wizard.oauthErr = `oauth: provider "huggingface" is not configured; set ZERO_OAUTH_HUGGINGFACE_CLIENT_ID`
+
+	view := strings.Join(wizard.renderProviderStep(72), "\n")
+	if !strings.Contains(view, "OAuth login failed") {
+		t.Fatalf("provider step should surface the OAuth error:\n%s", view)
+	}
+	if !strings.Contains(view, "huggingface.co/settings/applications/new") {
+		t.Fatalf("Hugging Face hint should point at app registration:\n%s", view)
+	}
+}
+
 func TestProviderWizardDeviceErrorSurfaced(t *testing.T) {
 	m := mouseTestModel()
 	m.providerWizard = m.newProviderWizard()

internal/tui/rendering.go

@@ -36,7 +36,7 @@ func pickerBusyText(name string) string {
 			Title: "Busy",
 			Lines: []string{"Can't change " + label + " while a run is in progress."},
 		}},
-		Hints: []string{"press Esc to cancel the run, then try again"},
+		Hints: []string{"press Esc twice to cancel the run, then try again"},
 	})
 }
 

internal/tui/session_test.go

@@ -775,6 +775,8 @@ func TestEscCancelRecordsSessionError(t *testing.T) {
 		t.Fatal("expected prompt submit to start an agent run")
 	}
 
+	updated, _ = next.Update(testKey(tea.KeyEsc))
+	next = updated.(model)
 	updated, _ = next.Update(testKey(tea.KeyEsc))
 	next = updated.(model)
 
@@ -836,7 +838,10 @@ func TestCancelledRunFlushesCheckpointSessionEvents(t *testing.T) {
 		next = updated.(model)
 		if _, ok := runtimeMsg.(permissionRequestMsg); ok {
 			// Cancel mid-run via Esc while the permission prompt is pending: this
-			// unblocks the goroutine through ctx cancellation.
+			// unblocks the goroutine through ctx cancellation. Esc now requires a
+			// second press within the confirmation window to actually cancel.
+			updated, _ = next.Update(testKey(tea.KeyEsc))
+			next = updated.(model)
 			updated, _ = next.Update(testKey(tea.KeyEsc))
 			next = updated.(model)
 			cancelled = true

internal/tui/theme.go

@@ -12,7 +12,8 @@ import (
 // may be swapped at startup (background detection / ZERO_THEME / --theme) or live
 // via /theme. Colors are truecolor hex; lipgloss downsamples on limited displays
 // and renders plain text when there is no TTY (tests). Every renderer consumes
-// these named styles — no hex literal may appear outside this file.
+// these named styles — no hex literal may appear outside theme_palettes.go (the
+// palette tables + theme registry).
 type tuiTheme struct {
 	// Base tokens.
 	ink        lipgloss.Style // primary text
@@ -92,9 +93,10 @@ type tuiTheme struct {
 }
 
 // palette is the raw color-token table for one theme. buildTheme turns it into a
-// resolved tuiTheme. darkPalette and lightPalette are the ONLY place hex literals
-// live. All dark tints stay darker than ink so every pairing survives 256-color
-// downsampling; the light set is dark-on-light with the same intent inverted.
+// resolved tuiTheme. The palette literals and the ordered theme registry live in
+// theme_palettes.go (the only place hex literals live). Dark palettes keep tints
+// darker than ink so every pairing survives 256-color downsampling; light palettes
+// are dark-on-light with the same intent inverted.
 type palette struct {
 	panel     string // card backgrounds (the terminal canvas itself is never painted full-bleed)
 	promptBg  string // submitted user prompt background
@@ -125,73 +127,6 @@ type palette struct {
 	cardPerm  string // permission card border (amber mixed into line)
 }
 
-// darkPalette is the original Lime palette: a near-black chat surface with one
-// lime accent. bg (#070708) is the terminal's own canvas — deliberately never
-// painted — so no token references it.
-var darkPalette = palette{
-	panel:     "#0e0e10",
-	promptBg:  "#262626",
-	line:      "#242429",
-	line2:     "#414147",
-	ink:       "#ececee",
-	muted:     "#9a9aa2", // secondary text — lifted so it clearly out-ranks faint
-	faint:     "#8a8a92", // hints/metadata — nudged up to separate from faintest
-	faintest:  "#7c7c82", // line numbers/separators — pinned at the WCAG-AA floor on the dark panel
-	accent:    "#caff3f",
-	green:     "#5dd1a4",
-	red:       "#ff7a7a",
-	amber:     "#ffc25c",
-	blue:      "#7db4ff",
-	gitAdd:    "#7db87a",
-	gitDel:    "#b87a7a",
-	addBg:     "#18352c",
-	delBg:     "#241819",
-	addBgWord: "#2e654d", // changed span within an added line — brighter green (sep 1.83 vs addBg, addInk 7.1:1)
-	delBgWord: "#502d30", // changed span within a deleted line — brighter red (sep 1.44 vs delBg, delInk 7.7:1)
-	permBg:    "#1c1915",
-	selBg:     "#32401b", // selected row bg — brightened from #1d2114 so the highlighted row separates from the panel (sep 1.18→1.73) while ink label contrast stays ~9.4:1
-	addInk:    "#bdeed7",
-	delInk:    "#f2c4c4",
-	onAccent:  "#000000",
-	cardRun:   "#5a6b2e",
-	cardErr:   "#6b3434",
-	cardPerm:  "#6b5a2e",
-}
-
-// lightPalette is dark-on-light: light-gray surfaces with near-black ink. The
-// muted/faint/faintest grays get progressively LIGHTER (toward the surface) so the
-// same text hierarchy reads on white; the lime accent is darkened to keep contrast
-// against a light background, and the diff/permission tints become light surfaces.
-var lightPalette = palette{
-	panel:     "#ececed", // card backgrounds (slightly off-white)
-	promptBg:  "#dcdce0", // submitted prompt background
-	line:      "#cfcfd5", // default borders
-	line2:     "#b0b0b8", // emphasized borders
-	ink:       "#1b1b1d", // primary text (near-black)
-	muted:     "#4a4a52", // secondary text — darkened so it clearly out-ranks faint on light
-	faint:     "#57575f", // hints, metadata — nudged down to separate from faintest
-	faintest:  "#646469", // line numbers, separators — pinned at the WCAG-AA floor on the light panel
-	accent:    "#477006", // brand lime, darkened to AA contrast on light
-	green:     "#1c7a4a", // success / diff add
-	red:       "#c0322c", // errors / diff del
-	amber:     "#8f6200", // permission / warnings
-	blue:      "#1d5fd6", // grep locations
-	gitAdd:    "#2f7a3a", // footer PR diff additions
-	gitDel:    "#a83a3a", // footer PR diff deletions
-	addBg:     "#e2f3e6", // diff added-line bg (light green)
-	delBg:     "#fbe6e6", // diff deleted-line bg (light red)
-	addBgWord: "#97d3ab", // changed span within an added line — deeper green (sep 1.49 vs addBg, addInk 4.7:1)
-	delBgWord: "#f1b3b3", // changed span within a deleted line — deeper red (sep 1.48 vs delBg, delInk 4.6:1)
-	permBg:    "#fbf0d8", // permission card bg (light amber)
-	selBg:     "#cfe78f", // selected row bg (light accent) — deepened from #e7f2cd so it separates from the near-white panel (sep 1.01→1.15); ink label stays >12:1, faint ~5:1
-	addInk:    "#1d5b37", // added-line text
-	delInk:    "#8e2d2d", // deleted-line text
-	onAccent:  "#ffffff", // text on the (dark) accent/amber fills
-	cardRun:   "#94ad60", // running card border
-	cardErr:   "#cf9a9a", // errored card border
-	cardPerm:  "#c9ad7d", // permission card border
-}
-
 // buildTheme resolves a palette into the styles every renderer uses.
 func buildTheme(p palette) tuiTheme {
 	col := func(s string) color.Color { return lipgloss.Color(s) }

internal/tui/theme_palettes.go

@@ -0,0 +1,457 @@
+package tui
+
+import "strings"
+
+// theme_palettes.go is the sole home of raw color hex in the TUI: every palette
+// literal and the ordered theme registry live here, so theme.go stays hex-free
+// (just the palette struct, buildTheme, and the resolved tuiTheme). Adding a theme
+// is a new palette{...} literal plus one themeRegistry entry — nothing else.
+//
+// Contrast discipline: every palette must satisfy the same WCAG invariants the
+// built-ins do (asserted across the whole registry in theme_select_test.go): ink
+// and faintest ≥ AA on panel; onAccent ≥ AA on accent; addInk/delInk readable on
+// their diff bands and word spans; the muted>faint>faintest ramp monotonic toward
+// the surface; and selBg visibly separated from panel while its label stays legible.
+
+// darkPalette is the original Lime palette: a near-black chat surface with one
+// lime accent. bg (#070708) is the terminal's own canvas — deliberately never
+// painted — so no token references it.
+var darkPalette = palette{
+	panel:     "#0e0e10",
+	promptBg:  "#262626",
+	line:      "#242429",
+	line2:     "#414147",
+	ink:       "#ececee",
+	muted:     "#9a9aa2", // secondary text — lifted so it clearly out-ranks faint
+	faint:     "#8a8a92", // hints/metadata — nudged up to separate from faintest
+	faintest:  "#7c7c82", // line numbers/separators — pinned at the WCAG-AA floor on the dark panel
+	accent:    "#caff3f", // original bright lime (the brand accent)
+	green:     "#5dd1a4",
+	red:       "#ff7a7a",
+	amber:     "#ffc25c",
+	blue:      "#7db4ff",
+	gitAdd:    "#7db87a",
+	gitDel:    "#b87a7a",
+	addBg:     "#18352c",
+	delBg:     "#241819",
+	addBgWord: "#2e654d", // changed span within an added line — brighter green (sep 1.83 vs addBg, addInk 7.1:1)
+	delBgWord: "#502d30", // changed span within a deleted line — brighter red (sep 1.44 vs delBg, delInk 7.7:1)
+	permBg:    "#1c1915",
+	selBg:     "#32401b", // selected row bg — brightened from #1d2114 so the highlighted row separates from the panel (sep 1.18→1.73) while ink label contrast stays ~9.4:1
+	addInk:    "#bdeed7",
+	delInk:    "#f2c4c4",
+	onAccent:  "#000000",
+	cardRun:   "#5a6b2e",
+	cardErr:   "#6b3434",
+	cardPerm:  "#6b5a2e",
+}
+
+// draculaPalette — the Dracula scheme (dracula.com): muted-violet surface, purple
+// accent, high-chroma pink/green/cyan signals.
+var draculaPalette = palette{
+	panel:     "#282a36",
+	promptBg:  "#383c4d",
+	line:      "#363a4b",
+	line2:     "#484c62",
+	ink:       "#f8f8f2",
+	muted:     "#b9bccb",
+	faint:     "#a2a5b8",
+	faintest:  "#9195ac",
+	accent:    "#bd93f9",
+	green:     "#50fa7b",
+	red:       "#ff5555",
+	amber:     "#ffb86c",
+	blue:      "#8be9fd",
+	gitAdd:    "#77c58c",
+	gitDel:    "#d98d8d",
+	addBg:     "#1c3b2a",
+	delBg:     "#3a2026",
+	addBgWord: "#235035",
+	delBgWord: "#5e333b",
+	permBg:    "#322a1e",
+	selBg:     "#504482",
+	addInk:    "#cbf2dd",
+	delInk:    "#f4c9c9",
+	onAccent:  "#000000",
+	cardRun:   "#7c6aa6",
+	cardErr:   "#98505a",
+	cardPerm:  "#9a7c62",
+}
+
+// nordPalette — the Nord scheme (nordtheme.com): cool polar-night slate with a
+// frost-blue accent and desaturated aurora signals.
+var nordPalette = palette{
+	panel:     "#3b4252",
+	promptBg:  "#464f62",
+	line:      "#434c5e",
+	line2:     "#4c566a",
+	ink:       "#eceff4",
+	muted:     "#c8cfda",
+	faint:     "#b4bdcb",
+	faintest:  "#a5afc1",
+	accent:    "#88c0d0",
+	green:     "#a3be8c",
+	red:       "#bf616a",
+	amber:     "#d08770",
+	blue:      "#81a1c1",
+	gitAdd:    "#8ba077",
+	gitDel:    "#b0757d",
+	addBg:     "#37433a",
+	delBg:     "#45383d",
+	addBgWord: "#456d46",
+	delBgWord: "#6d4650",
+	permBg:    "#47413a",
+	selBg:     "#40688a",
+	addInk:    "#d6ecca",
+	delInk:    "#f0c6cb",
+	onAccent:  "#000000",
+	cardRun:   "#4c6672",
+	cardErr:   "#6b4a51",
+	cardPerm:  "#6a564d",
+}
+
+// gruvboxPalette — Gruvbox dark (medium): warm retro browns with an olive-green
+// accent and high-contrast cream ink.
+var gruvboxPalette = palette{
+	panel:     "#32302f",
+	promptBg:  "#3c3836",
+	line:      "#504945",
+	line2:     "#665c54",
+	ink:       "#ebdbb2",
+	muted:     "#c9b99a",
+	faint:     "#b7a78d",
+	faintest:  "#a89984",
+	accent:    "#8ec07c",
+	green:     "#b8bb26",
+	red:       "#fb4934",
+	amber:     "#fabd2f",
+	blue:      "#83a598",
+	gitAdd:    "#98971a",
+	gitDel:    "#cc241d",
+	addBg:     "#2f3a29",
+	delBg:     "#3b2b29",
+	addBgWord: "#3e5236",
+	delBgWord: "#593733",
+	permBg:    "#38331e",
+	selBg:     "#3d4e30",
+	addInk:    "#c5e6b0",
+	delInk:    "#f0c0bb",
+	onAccent:  "#000000",
+	cardRun:   "#6f8460",
+	cardErr:   "#a5493d",
+	cardPerm:  "#a5833a",
+}
+
+// tokyoNightPalette — Tokyo Night (storm): deep indigo surface, soft blue accent,
+// cool high-contrast ink.
+var tokyoNightPalette = palette{
+	panel:     "#1e2030",
+	promptBg:  "#2c3149",
+	line:      "#262a3d",
+	line2:     "#3b4261",
+	ink:       "#c8d3f5",
+	muted:     "#a9b1d0",
+	faint:     "#9099b2",
+	faintest:  "#838ba8",
+	accent:    "#82aaff",
+	green:     "#c3e88d",
+	red:       "#ff757f",
+	amber:     "#ffc777",
+	blue:      "#86e1fc",
+	gitAdd:    "#96bf7d",
+	gitDel:    "#c77e85",
+	addBg:     "#20303b",
+	delBg:     "#37222c",
+	addBgWord: "#2b5a4a",
+	delBgWord: "#5c2e3a",
+	permBg:    "#2a2419",
+	selBg:     "#2a385b",
+	addInk:    "#b8e4d3",
+	delInk:    "#f3c4cb",
+	onAccent:  "#000000",
+	cardRun:   "#4b5d8b",
+	cardErr:   "#7d4857",
+	cardPerm:  "#7d6954",
+}
+
+// catppuccinPalette — Catppuccin Mocha: soft lavender surface with a mauve accent
+// and pastel signals.
+var catppuccinPalette = palette{
+	panel:     "#1e1e2e",
+	promptBg:  "#34364b",
+	line:      "#313244",
+	line2:     "#45475a",
+	ink:       "#cdd6f4",
+	muted:     "#a6adc8",
+	faint:     "#9399b2",
+	faintest:  "#83889f",
+	accent:    "#cba6f7",
+	green:     "#a6e3a1",
+	red:       "#f38ba8",
+	amber:     "#f9e2af",
+	blue:      "#89b4fa",
+	gitAdd:    "#8cbf8a",
+	gitDel:    "#cc8a9b",
+	addBg:     "#24312b",
+	delBg:     "#3c2a32",
+	addBgWord: "#2f5140",
+	delBgWord: "#56333f",
+	permBg:    "#29261b",
+	selBg:     "#322e46",
+	addInk:    "#c4ecd6",
+	delInk:    "#f4cdd6",
+	onAccent:  "#000000",
+	cardRun:   "#7a6a99",
+	cardErr:   "#8a5b72",
+	cardPerm:  "#8d8274",
+}
+
+// oneDarkPalette — Atom One Dark: slate-gray surface with a blue accent.
+var oneDarkPalette = palette{
+	panel:     "#2e323b",
+	promptBg:  "#3a3f4a",
+	line:      "#393f4a",
+	line2:     "#4b525f",
+	ink:       "#abb2bf",
+	muted:     "#a2a9b6",
+	faint:     "#9aa1af",
+	faintest:  "#969cab",
+	accent:    "#61afef",
+	green:     "#98c379",
+	red:       "#e06c75",
+	amber:     "#e5c07b",
+	blue:      "#56b6c2",
+	gitAdd:    "#82a06a",
+	gitDel:    "#bd8087",
+	addBg:     "#2c382b",
+	delBg:     "#3a2d2f",
+	addBgWord: "#3d5a3a",
+	delBgWord: "#5c3e40",
+	permBg:    "#3c3826",
+	selBg:     "#354256",
+	addInk:    "#cdeab3",
+	delInk:    "#f0c3c7",
+	onAccent:  "#000000",
+	cardRun:   "#496c8c",
+	cardErr:   "#7c515b",
+	cardPerm:  "#7e735e",
+}
+
+// solarizedDarkPalette — Solarized Dark (Ethan Schoonover): the signature teal
+// base03/base02 surface with a cyan accent and the fixed accent wheel.
+var solarizedDarkPalette = palette{
+	panel:     "#073642",
+	promptBg:  "#0b3b46",
+	line:      "#123f48",
+	line2:     "#4b636c",
+	ink:       "#cdd6d6",
+	muted:     "#a9b3b3",
+	faint:     "#9ba5a5",
+	faintest:  "#929c9c",
+	accent:    "#3bb3a6", // solarized cyan, brightened to clear AA on the lifted base02 panel
+	green:     "#859900",
+	red:       "#dc322f",
+	amber:     "#b58900",
+	blue:      "#268bd2",
+	gitAdd:    "#93a05e",
+	gitDel:    "#c67b71",
+	addBg:     "#123f31",
+	delBg:     "#45302e",
+	addBgWord: "#1e5c44",
+	delBgWord: "#6a3f3a",
+	permBg:    "#2e2a18",
+	selBg:     "#17505a",
+	addInk:    "#c3ecd6",
+	delInk:    "#f2cbc6",
+	onAccent:  "#000000",
+	cardRun:   "#1d6b6c",
+	cardErr:   "#6d393d",
+	cardPerm:  "#5b6028",
+}
+
+// rosePinePalette — Rosé Pine (main): muted rose-quartz base with a soft-rose
+// accent and cool pine/foam signals.
+var rosePinePalette = palette{
+	panel:     "#1f1d2e",
+	promptBg:  "#2f2b47",
+	line:      "#2b2840",
+	line2:     "#403d52",
+	ink:       "#e0def4",
+	muted:     "#a8a3c0",
+	faint:     "#928ea9",
+	faintest:  "#8985a0",
+	accent:    "#ebbcba",
+	green:     "#31748f",
+	red:       "#eb6f92",
+	amber:     "#f6c177",
+	blue:      "#9ccfd8",
+	gitAdd:    "#5e88a2",
+	gitDel:    "#d589a7",
+	addBg:     "#1f2d3a",
+	delBg:     "#3a1f2d",
+	addBgWord: "#274b5e",
+	delBgWord: "#763a4f",
+	permBg:    "#4a3e3d",
+	selBg:     "#44415a",
+	addInk:    "#cfe8ef",
+	delInk:    "#f6c9cd",
+	onAccent:  "#000000",
+	cardRun:   "#7c6673",
+	cardErr:   "#7c4662",
+	cardPerm:  "#806857",
+}
+
+// everforestPalette — Everforest dark (medium): warm forest-gray surface with a
+// sage-green accent.
+var everforestPalette = palette{
+	panel:     "#333c43",
+	promptBg:  "#3d484d",
+	line:      "#414b52",
+	line2:     "#55636b",
+	ink:       "#d3c6aa",
+	muted:     "#b0bab0",
+	faint:     "#a4aea3",
+	faintest:  "#9ca99b",
+	accent:    "#a7c080",
+	green:     "#83c092",
+	red:       "#e67e80",
+	amber:     "#dbbc7f",
+	blue:      "#7fbbb3",
+	gitAdd:    "#8faa78",
+	gitDel:    "#c08888",
+	addBg:     "#2c3f37",
+	delBg:     "#3e3234",
+	addBgWord: "#324e3b",
+	delBgWord: "#573a3c",
+	permBg:    "#3c382d",
+	selBg:     "#3b482e",
+	addInk:    "#cfead0",
+	delInk:    "#f4cfcd",
+	onAccent:  "#000000",
+	cardRun:   "#798b6b",
+	cardErr:   "#9c676b",
+	cardPerm:  "#96896b",
+}
+
+// lightPalette is dark-on-light: a warm cream surface (so cards lift off the
+// terminal page, which Zero never paints) with near-black ink and an olive-lime
+// accent that keeps the brand identity while clearing AA on the light panel. The
+// muted/faint/faintest grays get progressively LIGHTER toward the surface; diff and
+// permission tints are light surfaces. Replaces the old flat cool-gray light set
+// whose muddy panel, sub-AA diff spans, and near-invisible selBg read as broken.
+var lightPalette = palette{
+	panel:     "#efebd4",
+	promptBg:  "#e3ddc2",
+	line:      "#d8d2bd",
+	line2:     "#b7b199",
+	ink:       "#22201a",
+	muted:     "#4b5149",
+	faint:     "#575e55",
+	faintest:  "#636a61",
+	accent:    "#54700a",
+	green:     "#1e725c",
+	red:       "#c02434",
+	amber:     "#8a5f00",
+	blue:      "#1f66c0",
+	gitAdd:    "#3d6f46",
+	gitDel:    "#a34a4a",
+	addBg:     "#ddf0df",
+	delBg:     "#f8dcdc",
+	addBgWord: "#a2daae",
+	delBgWord: "#f2b6b6",
+	permBg:    "#f7ebc6",
+	selBg:     "#d4e08f",
+	addInk:    "#0c4026",
+	delInk:    "#641a1d",
+	onAccent:  "#ffffff",
+	cardRun:   "#b0be7e",
+	cardErr:   "#d8b0a8",
+	cardPerm:  "#d6c496",
+}
+
+// solarizedLightPalette — Solarized Light: the base3/base2 cream surface with the
+// same fixed accent wheel as Solarized Dark, dark-on-light.
+var solarizedLightPalette = palette{
+	panel:     "#eee8d5",
+	promptBg:  "#e1d9be",
+	line:      "#d8d1bc",
+	line2:     "#c0b89e",
+	ink:       "#304049",
+	muted:     "#495b61",
+	faint:     "#506469",
+	faintest:  "#576b72",
+	accent:    "#0c665c", // solarized cyan, darkened for AA on the cream panel (with white onAccent)
+	green:     "#859900",
+	red:       "#dc322f",
+	amber:     "#7a5c00", // solarized yellow, darkened so white onAccent works on amber fills
+	blue:      "#268bd2",
+	gitAdd:    "#788d34",
+	gitDel:    "#ac4f50",
+	addBg:     "#dde8c6",
+	delBg:     "#f1ddd2",
+	addBgWord: "#b9d488", // deepened so the changed span separates from addBg (sep 1.28)
+	delBgWord: "#edc4b4",
+	permBg:    "#f0e6bd",
+	selBg:     "#a6d6c4",
+	addInk:    "#38480a",
+	delInk:    "#6f1614",
+	onAccent:  "#ffffff", // white — accent and amber are both dark on this light theme
+	cardRun:   "#7fbaaf",
+	cardErr:   "#d8837a",
+	cardPerm:  "#c4ae63",
+}
+
+// themeEntry is one registered theme: Name is the /theme value + ZERO_THEME/--theme
+// token (lowercase, kebab), Label is the picker display text, and IsDark groups the
+// picker (Dark/Light sections) and drives which built-in `auto` resolves to.
+type themeEntry struct {
+	Name    string
+	Label   string
+	Palette palette
+	IsDark  bool
+}
+
+// themeRegistry is the ordered source of truth for every selectable theme. Order is
+// the picker order: all Dark themes first, then all Light, with the brand
+// dark/light built-ins leading their groups. themeModes (theme_select.go) prepends
+// `auto` to this. Append here to add a theme — nothing else needs editing.
+var themeRegistry = []themeEntry{
+	{Name: "dark", Label: "dark", Palette: darkPalette, IsDark: true},
+	{Name: "dracula", Label: "Dracula", Palette: draculaPalette, IsDark: true},
+	{Name: "nord", Label: "Nord", Palette: nordPalette, IsDark: true},
+	{Name: "gruvbox", Label: "Gruvbox", Palette: gruvboxPalette, IsDark: true},
+	{Name: "tokyo-night", Label: "Tokyo Night", Palette: tokyoNightPalette, IsDark: true},
+	{Name: "catppuccin", Label: "Catppuccin", Palette: catppuccinPalette, IsDark: true},
+	{Name: "one-dark", Label: "One Dark", Palette: oneDarkPalette, IsDark: true},
+	{Name: "solarized-dark", Label: "Solarized Dark", Palette: solarizedDarkPalette, IsDark: true},
+	{Name: "rose-pine", Label: "Rosé Pine", Palette: rosePinePalette, IsDark: true},
+	{Name: "everforest", Label: "Everforest", Palette: everforestPalette, IsDark: true},
+	{Name: "light", Label: "light", Palette: lightPalette, IsDark: false},
+	{Name: "solarized-light", Label: "Solarized Light", Palette: solarizedLightPalette, IsDark: false},
+}
+
+// themeByName indexes the registry by lowercased name for O(1) lookup. Built as a
+// var initializer (not init()) so it is ready before themeModes' package-var
+// initializer calls themeNames().
+var themeByName = func() map[string]themeEntry {
+	byName := make(map[string]themeEntry, len(themeRegistry))
+	for _, entry := range themeRegistry {
+		byName[entry.Name] = entry
+	}
+	return byName
+}()
+
+// lookupTheme resolves a theme name (case/space-insensitive) to its entry.
+func lookupTheme(name string) (themeEntry, bool) {
+	entry, ok := themeByName[strings.ToLower(strings.TrimSpace(name))]
+	return entry, ok
+}
+
+// themeNames returns every registered theme name in registry (picker) order.
+func themeNames() []string {
+	names := make([]string, len(themeRegistry))
+	for index, entry := range themeRegistry {
+		names[index] = entry.Name
+	}
+	return names
+}

internal/tui/theme_picker_test.go

@@ -0,0 +1,340 @@
+package tui
+
+import (
+	"context"
+	"encoding/json"
+	"os"
+	"path/filepath"
+	"reflect"
+	"testing"
+
+	tea "charm.land/bubbletea/v2"
+)
+
+// A committed theme is written to user config and reloaded at startup (via
+// Options.SavedTheme -> resolveThemeMode), so a /theme choice survives restart.
+func TestThemeChoicePersistsAcrossRestart(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	cfgPath := filepath.Join(t.TempDir(), "config.json")
+
+	// First session: pick a color theme via the /theme command (same commit path the
+	// picker uses).
+	m := newModel(context.Background(), Options{UserConfigPath: cfgPath})
+	m, _ = m.handleThemeCommand("dracula")
+	if m.themeMode != themeMode("dracula") {
+		t.Fatalf("themeMode = %q, want dracula", m.themeMode)
+	}
+	data, err := os.ReadFile(cfgPath)
+	if err != nil {
+		t.Fatalf("theme commit should have written config: %v", err)
+	}
+	var cfg struct {
+		Preferences struct {
+			Theme string `json:"theme"`
+		} `json:"preferences"`
+	}
+	if err := json.Unmarshal(data, &cfg); err != nil {
+		t.Fatalf("config is not valid JSON: %v", err)
+	}
+	if cfg.Preferences.Theme != "dracula" {
+		t.Fatalf("preferences.theme = %q, want dracula", cfg.Preferences.Theme)
+	}
+
+	// Second session: the persisted theme seeds startup (no flag / env).
+	restarted := newModel(context.Background(), Options{UserConfigPath: cfgPath, SavedTheme: "dracula"})
+	if restarted.themeMode != themeMode("dracula") {
+		t.Fatalf("restarted themeMode = %q, want dracula (from saved config)", restarted.themeMode)
+	}
+}
+
+// resolveThemeMode precedence: flag > ZERO_THEME > persisted config > auto.
+func TestResolveThemeModeConfigFallback(t *testing.T) {
+	if got := resolveThemeMode("", "", "nord"); got != themeMode("nord") {
+		t.Errorf("saved-only = %q, want nord", got)
+	}
+	if got := resolveThemeMode("dracula", "", "nord"); got != themeMode("dracula") {
+		t.Errorf("flag should beat saved: got %q, want dracula", got)
+	}
+	if got := resolveThemeMode("", "gruvbox", "nord"); got != themeMode("gruvbox") {
+		t.Errorf("env should beat saved: got %q, want gruvbox", got)
+	}
+	if got := resolveThemeMode("", "", "bogus-theme"); got != themeAuto {
+		t.Errorf("unknown saved theme should fall back to auto, got %q", got)
+	}
+}
+
+// themePickerRowIndex finds the picker row whose Value is name (index-independent,
+// so tests survive registry reordering / additions).
+func themePickerRowIndex(t *testing.T, p *commandPicker, name string) int {
+	t.Helper()
+	for i, item := range p.items {
+		if item.Value == name {
+			return i
+		}
+	}
+	t.Fatalf("theme picker has no row for %q", name)
+	return -1
+}
+
+// assertPreviewMatchesSelection checks the live palette equals the palette of the
+// currently highlighted theme row (the auto row has no palette of its own).
+func assertPreviewMatchesSelection(t *testing.T, m model) {
+	t.Helper()
+	sel := m.picker.items[m.picker.selected]
+	entry, ok := lookupTheme(sel.Value)
+	if !ok {
+		return
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, entry.Palette.ink) {
+		t.Errorf("preview of %q did not apply its palette (ink mismatch)", sel.Value)
+	}
+}
+
+// Bare `/theme` opens the popup picker (like /model and /effort) with one row per
+// theme mode, preselecting the active preference. An explicit `/theme <mode>` must
+// keep taking the text path so scripts and the existing state view still work.
+func TestThemePickerOpensOnBareTheme(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeLight
+	m.input.SetValue("/theme")
+
+	updated, cmd := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+	if cmd != nil {
+		t.Fatalf("opening the theme picker should not emit a cmd, got %T", cmd)
+	}
+	if m.picker == nil || m.picker.kind != pickerTheme {
+		t.Fatalf("expected the theme picker to open, got %#v", m.picker)
+	}
+	if len(m.picker.items) != len(themeModes) {
+		t.Fatalf("picker has %d items, want %d", len(m.picker.items), len(themeModes))
+	}
+	for i, want := range themeModes {
+		if m.picker.items[i].Value != want {
+			t.Errorf("item %d value = %q, want %q", i, m.picker.items[i].Value, want)
+		}
+	}
+	if got := m.picker.items[m.picker.selected].Value; got != string(themeLight) {
+		t.Errorf("preselected value = %q, want the active mode %q", got, themeLight)
+	}
+}
+
+// An explicit mode argument runs the text handler directly and never opens the
+// popup — guards the dispatch branch and keeps /theme <mode> scriptable.
+func TestThemeArgSkipsPicker(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.input.SetValue("/theme dark")
+
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+	if m.picker != nil {
+		t.Fatalf("explicit /theme dark must not open a picker, got %#v", m.picker)
+	}
+	if m.themeMode != themeDark {
+		t.Fatalf("after /theme dark, mode = %q", m.themeMode)
+	}
+}
+
+// Moving the cursor live-previews each palette: the global zeroTheme swaps as the
+// selection changes, so the whole UI (and the overlay) repaints in the hovered
+// theme without committing the preference.
+func TestThemePickerPreviewsOnMove(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.hasDarkBg = true
+	applyTheme(themeDark, true)
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	// Each Down moves to the next theme and live-applies its palette; Up follows back.
+	for i := 0; i < 3; i++ {
+		updated, _ = m.Update(testKey(tea.KeyDown))
+		m = updated.(model)
+		assertPreviewMatchesSelection(t, m)
+	}
+	updated, _ = m.Update(testKey(tea.KeyUp))
+	m = updated.(model)
+	assertPreviewMatchesSelection(t, m)
+
+	// Preview must not have written the committed preference.
+	if m.themeMode != themeDark {
+		t.Errorf("preview mutated the committed mode to %q", m.themeMode)
+	}
+}
+
+// Enter on a fixed mode commits it: the palette stays applied, the preference is
+// recorded, the popup closes, and the switch is noted in the transcript.
+func TestThemePickerCommitAppliesAndRecords(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.hasDarkBg = true
+	applyTheme(themeDark, true)
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	// Choose a color theme by locating its row (index-independent), then confirm.
+	m.picker.selected = themePickerRowIndex(t, m.picker, "dracula")
+	updated, cmd := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+	if cmd != nil {
+		t.Fatalf("committing a fixed theme should not emit a cmd, got %T", cmd)
+	}
+	if m.picker != nil {
+		t.Fatal("committing should close the picker")
+	}
+	if m.themeMode != themeMode("dracula") {
+		t.Fatalf("committed mode = %q, want dracula", m.themeMode)
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, draculaPalette.ink) {
+		t.Error("commit did not leave the dracula palette applied")
+	}
+	if !transcriptContains(m.transcript, "active theme") {
+		t.Errorf("commit should record the switch in the transcript:\n%s", transcriptText(m.transcript))
+	}
+}
+
+// Committing `auto` re-probes the terminal background (like the text dispatch) so
+// the palette re-detects light/dark instead of reusing the preview's reading.
+func TestThemePickerAutoCommitReprobesBackground(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	m.picker.selected = 0 // "auto"
+	updated, cmd := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+	if m.themeMode != themeAuto {
+		t.Fatalf("committed mode = %q, want auto", m.themeMode)
+	}
+	if cmd == nil {
+		t.Fatal("committing auto must return a background re-probe cmd")
+	}
+	if reflect.ValueOf(cmd).Pointer() != reflect.ValueOf(tea.RequestBackgroundColor).Pointer() {
+		t.Error("committing auto must return tea.RequestBackgroundColor")
+	}
+}
+
+// Typing to filter the list re-previews the newly-highlighted mode, so the applied
+// palette never diverges from the row the popup points at. Backspacing back to an
+// empty query re-previews the (restored) selection too.
+func TestThemePickerFilterRePreviews(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.hasDarkBg = true
+	applyTheme(themeDark, true)
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	// Preview light by moving, then filter to "light" — the applied palette must
+	// track the filtered highlight (still light here), not lag behind.
+	updated, _ = m.Update(testKey(tea.KeyDown)) // dark -> light preview
+	m = updated.(model)
+	updated, _ = m.Update(testKeyText("l"))
+	m = updated.(model)
+	updated, _ = m.Update(testKeyText("i"))
+	m = updated.(model)
+	if got := m.picker.items[m.picker.selected].Value; got != string(themeLight) {
+		t.Fatalf("filter 'li' should highlight light, got %q", got)
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, lightPalette.ink) {
+		t.Error("filtering to light did not keep the light palette previewed")
+	}
+
+	// Re-filter to "dark": highlight and preview must both switch to dark.
+	updated, _ = m.Update(testKey(tea.KeyBackspace))
+	m = updated.(model)
+	updated, _ = m.Update(testKey(tea.KeyBackspace))
+	m = updated.(model)
+	updated, _ = m.Update(testKeyText("d"))
+	m = updated.(model)
+	if got := m.picker.items[m.picker.selected].Value; got != string(themeDark) {
+		t.Fatalf("filter 'd' should highlight dark, got %q", got)
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, darkPalette.ink) {
+		t.Error("filtering to dark did not re-preview the dark palette")
+	}
+}
+
+// A filter that matches nothing must not strand the last preview: the palette
+// falls back to the committed theme, and committing (Enter on the empty list) is a
+// clean no-op that leaves the committed mode and palette in agreement.
+func TestThemePickerEmptyFilterRestoresCommitted(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.hasDarkBg = true
+	applyTheme(themeDark, true)
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	// Preview another theme by moving, then type a char that matches no theme name
+	// ('q' appears in none) -> the list empties.
+	updated, _ = m.Update(testKey(tea.KeyDown))
+	m = updated.(model)
+	updated, _ = m.Update(testKeyText("q"))
+	m = updated.(model)
+	if len(m.picker.items) != 0 {
+		t.Fatalf("filter 'q' should match no theme, got %d items", len(m.picker.items))
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, darkPalette.ink) {
+		t.Error("an empty filter should restore the committed dark palette, not keep the preview")
+	}
+
+	// Enter on the empty list closes the picker without changing the committed
+	// preference, and leaves the palette matching it.
+	updated, _ = m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+	if m.picker != nil {
+		t.Fatal("Enter on an empty filter should close the picker")
+	}
+	if m.themeMode != themeDark {
+		t.Fatalf("empty-list commit must not change the mode, got %q", m.themeMode)
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, darkPalette.ink) {
+		t.Error("after an empty-list commit the palette must match the committed dark mode")
+	}
+}
+
+// Esc dismisses the picker without choosing and restores the committed palette,
+// undoing whatever the live preview applied.
+func TestThemePickerEscRestoresCommittedTheme(t *testing.T) {
+	defer applyTheme(themeDark, true)
+	m := newModel(context.Background(), Options{})
+	m.themeMode = themeDark
+	m.hasDarkBg = true
+	applyTheme(themeDark, true)
+	m.input.SetValue("/theme")
+	updated, _ := m.Update(testKey(tea.KeyEnter))
+	m = updated.(model)
+
+	// Preview another theme by moving, then bail out.
+	updated, _ = m.Update(testKey(tea.KeyDown))
+	m = updated.(model)
+	assertPreviewMatchesSelection(t, m)
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r == mustR(t, darkPalette.ink) {
+		t.Fatal("expected a non-dark preview to be applied before Esc")
+	}
+	updated, _ = m.Update(testKey(tea.KeyEsc))
+	m = updated.(model)
+	if m.picker != nil {
+		t.Fatal("Esc should close the picker")
+	}
+	if m.themeMode != themeDark {
+		t.Fatalf("Esc must not change the committed mode, got %q", m.themeMode)
+	}
+	if r, _, _, _ := zeroTheme.inkColor.RGBA(); r != mustR(t, darkPalette.ink) {
+		t.Error("Esc did not restore the committed dark palette")
+	}
+}

internal/tui/theme_select.go

@@ -1,6 +1,10 @@
 package tui
 
-import "strings"
+import (
+	"strings"
+
+	"github.com/Gitlawb/zero/internal/config"
+)
 
 // themeMode is the operator's palette preference.
 type themeMode string
@@ -11,34 +15,49 @@ const (
 	themeLight themeMode = "light"
 )
 
-// themeModes lists the values /theme accepts.
-var themeModes = []string{string(themeAuto), string(themeDark), string(themeLight)}
+// themeModes lists the values /theme accepts, in picker order: `auto` first, then
+// every registered theme (theme_palettes.go). It is the single ordered source
+// feeding both the picker and the /theme state list — adding a registry entry
+// extends it automatically.
+var themeModes = append([]string{string(themeAuto)}, themeNames()...)
 
-// resolveThemeMode picks the preference in precedence order: an explicit value
-// (the --theme flag, threaded via Options.Theme), then ZERO_THEME, then auto.
-func resolveThemeMode(flagValue, envValue string) themeMode {
-	for _, v := range []string{flagValue, envValue} {
-		switch strings.ToLower(strings.TrimSpace(v)) {
-		case "dark":
-			return themeDark
-		case "light":
-			return themeLight
-		case "auto":
+// resolveThemeMode picks the first accepted preference from candidates in
+// precedence order — the caller passes them highest-first: the --theme flag, then
+// ZERO_THEME, then the persisted config theme. A value is accepted if it is `auto`
+// or names a registered theme; unrecognized/blank values are skipped, and an empty
+// list (or all-unrecognized) falls back to auto.
+func resolveThemeMode(candidates ...string) themeMode {
+	for _, v := range candidates {
+		s := strings.ToLower(strings.TrimSpace(v))
+		if s == "" {
+			continue
+		}
+		if s == string(themeAuto) {
 			return themeAuto
 		}
+		if _, ok := lookupTheme(s); ok {
+			return themeMode(s)
+		}
 	}
 	return themeAuto
 }
 
-// validThemeMode reports whether s names a theme mode (for /theme validation).
+// validThemeMode reports whether s names a theme mode (for /theme validation):
+// `auto` or any registered theme.
 func validThemeMode(s string) bool {
-	switch themeMode(strings.ToLower(strings.TrimSpace(s))) {
-	case themeAuto, themeDark, themeLight:
+	s = strings.ToLower(strings.TrimSpace(s))
+	if s == string(themeAuto) {
 		return true
 	}
-	return false
+	_, ok := lookupTheme(s)
+	return ok
 }
 
+// ValidThemeArg reports whether s is an acceptable --theme / ZERO_THEME value
+// (`auto` or a registered theme name). Exported so the CLI flag validator shares
+// this one source of truth instead of hardcoding the theme list.
+func ValidThemeArg(s string) bool { return validThemeMode(s) }
+
 // applyTheme swaps the active palette (zeroTheme) and the globals derived from it
 // — the streaming-fade ramp and the static render cache — so a switch repaints
 // every subsequent render. For themeAuto it resolves to dark/light from
@@ -53,12 +72,13 @@ func applyTheme(mode themeMode, hasDarkBackground bool) themeMode {
 			resolved = themeLight
 		}
 	}
-	switch resolved {
-	case themeLight:
-		zeroTheme = buildTheme(lightPalette)
-	default:
-		zeroTheme = buildTheme(darkPalette)
+	// Resolve the (now concrete) mode to its registered palette; an unknown name
+	// falls back to the dark built-in so a bad value can never leave zeroTheme unset.
+	entry, ok := lookupTheme(string(resolved))
+	if !ok {
+		entry, _ = lookupTheme(string(themeDark))
 	}
+	zeroTheme = buildTheme(entry.Palette)
 	rebuildStreamingFadePalette()
 	if defaultRenderCache != nil {
 		defaultRenderCache.clear() // old-palette entries must not be reused
@@ -66,15 +86,45 @@ func applyTheme(mode themeMode, hasDarkBackground bool) themeMode {
 	return resolved
 }
 
-// handleThemeCommand implements /theme [auto|dark|light]: no arg shows state, a
-// valid mode switches the active palette live. Mirrors handleStyleCommand.
+// previewSelectedTheme makes the live palette match the theme picker's current
+// state: the highlighted mode when a row is selectable, or the committed
+// m.themeMode when the filter matches nothing. Called on every change to the
+// picker's selection or filter (arrow/wheel moves, mouse, and query typing) so the
+// whole UI — and the overlay itself — always renders the mode the popup points at,
+// and never strands on a stale preview. It only swaps the global zeroTheme via
+// applyTheme; m.themeMode keeps the committed preference so Esc can restore it. A
+// no-op unless a theme picker is open. Runs on the Update goroutine, like every
+// zeroTheme access.
+func (m model) previewSelectedTheme() {
+	if m.picker == nil || m.picker.kind != pickerTheme {
+		return
+	}
+	if item, ok := m.picker.current(); ok {
+		applyTheme(themeMode(item.Value), m.hasDarkBg)
+		return
+	}
+	// No selectable row (the filter matched nothing): fall back to the committed
+	// theme rather than leaving the previous preview applied.
+	m.restoreCommittedTheme()
+}
+
+// restoreCommittedTheme re-applies m.themeMode after a /theme preview is dismissed
+// without choosing (Esc). Preview never wrote m.themeMode, so it still holds the
+// real preference; re-applying repaints back to it.
+func (m model) restoreCommittedTheme() {
+	applyTheme(m.themeMode, m.hasDarkBg)
+}
+
+// handleThemeCommand implements /theme [name]: `list` shows state, a registered
+// theme name (or `auto`) switches the active palette live. Bare `/theme` opens the
+// picker at the dispatch layer, so it never reaches here empty. Mirrors handleStyleCommand.
 func (m model) handleThemeCommand(args string) (model, string) {
 	arg := strings.ToLower(strings.TrimSpace(args))
 	if arg == "" || arg == "list" {
 		return m, m.themeStateText()
 	}
 	if !validThemeMode(arg) {
-		return m, "Theme\nUnknown theme: " + arg + " (use auto, dark, or light)"
+		return m, "Theme\nUnknown theme: " + arg + " (use /theme with no argument to pick from the list)"
 	}
 	m.themeMode = themeMode(arg)
 	resolved := applyTheme(m.themeMode, m.hasDarkBg)
@@ -82,11 +132,31 @@ func (m model) handleThemeCommand(args string) (model, string) {
 	if m.themeMode == themeAuto {
 		active = "auto (" + string(resolved) + ")"
 	}
-	return m, strings.Join([]string{
+	lines := []string{
 		"Theme",
 		"active theme: " + active,
 		"Already-printed scrollback keeps its previous colors; new output uses the new theme.",
-	}, "\n")
+	}
+	// Commit path (both /theme <name> and the picker route through here): persist the
+	// choice so it survives restart. Previews call applyTheme directly and never reach here.
+	if note := m.persistThemePreference(); note != "" {
+		lines = append(lines, note)
+	}
+	return m, strings.Join(lines, "\n")
+}
+
+// persistThemePreference writes the committed theme to user config so it is applied
+// again at startup (via Options.SavedTheme -> resolveThemeMode). Best-effort: returns
+// a short note to surface on failure, or "" on success / when there is no config
+// path (e.g. tests). Never called from the live-preview path.
+func (m model) persistThemePreference() string {
+	if strings.TrimSpace(m.userConfigPath) == "" {
+		return ""
+	}
+	if _, err := config.SetTheme(m.userConfigPath, string(m.themeMode)); err != nil {
+		return "note: could not save theme preference (" + err.Error() + ")"
+	}
+	return ""
 }
 
 // themeStateText renders the /theme state view.
@@ -109,6 +179,6 @@ func (m model) themeStateText() string {
 				"available: " + strings.Join(themeModes, ", "),
 			},
 		}},
-		Hints: []string{"use /theme <auto|dark|light> to switch this TUI session"},
+		Hints: []string{"run /theme with no argument to open the picker, or /theme <name> to switch directly"},
 	})
 }

internal/tui/theme_select_test.go

@@ -52,24 +52,19 @@ func wcagRatio(t *testing.T, fg, bg string) float64 {
 // The word-level diff's brighter changed-span band must keep its text AA-readable
 // and stay clearly distinct from the base add/del band, on both themes.
 func TestDiffWordSpanContrast(t *testing.T) {
-	for _, c := range []struct {
-		name string
-		pal  palette
-	}{
-		{"dark", darkPalette},
-		{"light", lightPalette},
-	} {
-		if r := wcagRatio(t, c.pal.addInk, c.pal.addBgWord); r < 4.5 {
-			t.Errorf("%s: addInk on addBgWord %.2f < 4.5 (AA)", c.name, r)
+	for _, entry := range themeRegistry {
+		name, pal := entry.Name, entry.Palette
+		if r := wcagRatio(t, pal.addInk, pal.addBgWord); r < 4.5 {
+			t.Errorf("%s: addInk on addBgWord %.2f < 4.5 (AA)", name, r)
 		}
-		if r := wcagRatio(t, c.pal.delInk, c.pal.delBgWord); r < 4.5 {
-			t.Errorf("%s: delInk on delBgWord %.2f < 4.5 (AA)", c.name, r)
+		if r := wcagRatio(t, pal.delInk, pal.delBgWord); r < 4.5 {
+			t.Errorf("%s: delInk on delBgWord %.2f < 4.5 (AA)", name, r)
 		}
-		if sep := wcagRatio(t, c.pal.addBgWord, c.pal.addBg); sep < 1.2 {
-			t.Errorf("%s: addBgWord vs addBg separation %.2f < 1.2 (span not distinct)", c.name, sep)
+		if sep := wcagRatio(t, pal.addBgWord, pal.addBg); sep < 1.2 {
+			t.Errorf("%s: addBgWord vs addBg separation %.2f < 1.2 (span not distinct)", name, sep)
 		}
-		if sep := wcagRatio(t, c.pal.delBgWord, c.pal.delBg); sep < 1.2 {
-			t.Errorf("%s: delBgWord vs delBg separation %.2f < 1.2 (span not distinct)", c.name, sep)
+		if sep := wcagRatio(t, pal.delBgWord, pal.delBg); sep < 1.2 {
+			t.Errorf("%s: delBgWord vs delBg separation %.2f < 1.2 (span not distinct)", name, sep)
 		}
 	}
 }
@@ -78,18 +73,52 @@ func TestDiffWordSpanContrast(t *testing.T) {
 // AND keep its label readable. Guards the regression this fixes: the light
 // selBg (#e7f2cd) sat at 1.01 vs the panel (#ececed) — effectively invisible.
 func TestSelectedRowBandIsVisibleAndReadable(t *testing.T) {
-	for _, c := range []struct {
-		name string
-		pal  palette
-	}{
-		{"dark", darkPalette},
-		{"light", lightPalette},
-	} {
-		if r := wcagRatio(t, c.pal.ink, c.pal.selBg); r < 4.5 {
-			t.Errorf("%s: ink on selBg contrast %.2f < 4.5 — selected-row label unreadable", c.name, r)
+	for _, entry := range themeRegistry {
+		name, pal := entry.Name, entry.Palette
+		if r := wcagRatio(t, pal.ink, pal.selBg); r < 4.5 {
+			t.Errorf("%s: ink on selBg contrast %.2f < 4.5 — selected-row label unreadable", name, r)
 		}
-		if sep := wcagRatio(t, c.pal.selBg, c.pal.panel); sep < 1.10 {
-			t.Errorf("%s: selBg vs panel separation %.2f < 1.10 — selected row does not stand out", c.name, sep)
+		if sep := wcagRatio(t, pal.selBg, pal.panel); sep < 1.10 {
+			t.Errorf("%s: selBg vs panel separation %.2f < 1.10 — selected row does not stand out", name, sep)
+		}
+	}
+}
+
+// Every registered theme — not just the two built-ins — must clear WCAG AA on its
+// text-bearing tokens against the panel and keep the muted>faint>faintest>panel
+// gray ramp monotonic in its polarity (light-on-dark for dark themes, the inverse
+// for light themes). Guards that a newly-added color palette can't ship illegible.
+func TestAllThemesContrastAndHierarchy(t *testing.T) {
+	for _, entry := range themeRegistry {
+		pal := entry.Palette
+		for _, tok := range []struct {
+			name string
+			fg   string
+		}{
+			{"ink", pal.ink}, {"muted", pal.muted}, {"faint", pal.faint},
+			{"faintest", pal.faintest}, {"accent", pal.accent},
+		} {
+			if r := wcagRatio(t, tok.fg, pal.panel); r < 4.5 {
+				t.Errorf("%s %s on panel %.2f < 4.5 (WCAG AA)", entry.Name, tok.name, r)
+			}
+		}
+		if r := wcagRatio(t, pal.onAccent, pal.accent); r < 4.5 {
+			t.Errorf("%s onAccent on accent %.2f < 4.5 (WCAG AA)", entry.Name, r)
+		}
+		// Gray ramp ordered ink -> muted -> faint -> faintest -> panel; luminance
+		// rises toward the surface on light themes, falls on dark themes.
+		chain := []float64{
+			relLum(t, pal.ink), relLum(t, pal.muted), relLum(t, pal.faint),
+			relLum(t, pal.faintest), relLum(t, pal.panel),
+		}
+		for i := 1; i < len(chain); i++ {
+			ok := chain[i] > chain[i-1]
+			if entry.IsDark {
+				ok = chain[i] < chain[i-1]
+			}
+			if !ok {
+				t.Errorf("%s hierarchy not monotonic toward surface at %d: %v", entry.Name, i, chain)
+			}
 		}
 	}
 }

internal/tui/transcript_view.go

@@ -5,6 +5,11 @@ import "strings"
 func (m model) toggleDetailedTranscript() model {
 	m.transcriptDetailed = !m.transcriptDetailed
 	m.clearSuggestions()
+	if m.picker != nil && m.picker.kind == pickerTheme {
+		// Dropping a theme picker mid-preview must undo the live palette, or the
+		// previewed theme would stick while m.themeMode still holds the old one.
+		m.restoreCommittedTheme()
+	}
 	m.picker = nil
 	return m
 }

internal/tui/view.go

@@ -201,6 +201,9 @@ func (m model) statusLine(width int) string {
 		if m.exitConfirmActive {
 			return fitStyledLine(prefix+zeroTheme.amber.Render("●")+" "+zeroTheme.amber.Render(ctrlCExitConfirmText), width)
 		}
+		if m.cancelConfirmActive {
+			return fitStyledLine(prefix+zeroTheme.amber.Render("●")+" "+zeroTheme.amber.Render(escCancelConfirmText), width)
+		}
 		return fitStyledLine(left, width)
 	}
 
@@ -210,6 +213,8 @@ func (m model) statusLine(width int) string {
 	}
 	if m.exitConfirmActive {
 		left = prefix + zeroTheme.amber.Render("●") + " " + zeroTheme.amber.Render(ctrlCExitConfirmText)
+	} else if m.cancelConfirmActive {
+		left = prefix + zeroTheme.amber.Render("●") + " " + zeroTheme.amber.Render(escCancelConfirmText)
 	} else if summary := m.backgroundTerminalSummary(); summary != "" {
 		left += separator + zeroTheme.muted.Render(summary)
 	}
@@ -218,15 +223,19 @@ func (m model) statusLine(width int) string {
 	// Context-fill gauge: surface it down to the narrow tier (where it matters
 	// most), but skip it when the context sidebar is already showing the % so the
 	// figure isn't duplicated.
+	gaugeShown := false
 	if tier >= tierNarrow && !m.sidebarActive() {
 		if gauge := m.contextWindowSegment(); gauge != "" {
 			rightGroups = append(rightGroups, gauge)
+			gaugeShown = true
 		}
 	}
-	// The sidebar pins the token readout at its floor, so when it's open keep
-	// only the cost here — otherwise the token figure shows on both sides.
+	// The sidebar pins the token readout at its floor, and the gauge's "used"
+	// figure is the exact same number (both read latestUsageTokens) — either
+	// one showing means the plain usage segment must drop its own token count
+	// to just the cost, or the count renders twice side by side.
 	usage := m.usageStatusSegment()
-	if m.sidebarActive() {
+	if m.sidebarActive() || gaugeShown {
 		usage = m.usageCostSegment()
 	}
 	if usage != "" {

internal/tui/working_status_test.go

@@ -106,6 +106,46 @@ func TestQuietGenerationHint(t *testing.T) {
 	}
 }
 
+// TestQuietGenerationHintEscalatesPastHalfIdleTimeout: a heartbeating-but-
+// silent stream (chatgpt/gpt-5.x, ollama reasoning models — see
+// providerio.ErrStreamStalled) and a genuinely healthy-but-slow one look
+// identical under the plain "still generating… Xs" cue — the ticking number
+// is the only signal, whether real content is still coming or nothing ever
+// will. Past half the provider's idle timeout the cue must say so explicitly
+// and name when Zero's own content-stall watchdog will act, rather than
+// leaving the user to guess whether this is a hang.
+func TestQuietGenerationHintEscalatesPastHalfIdleTimeout(t *testing.T) {
+	// 30s idle timeout: half (15s) sits comfortably above quietWorkingHint (8s),
+	// leaving a clean window to observe the plain cue before it escalates.
+	t.Setenv("ZERO_STREAM_IDLE_TIMEOUT", "30s")
+	base := time.Date(2026, 6, 25, 12, 0, 0, 0, time.UTC)
+	m := model{now: func() time.Time { return base }}
+	m.activeRunID = 7
+	m.turnStartedAt = base
+
+	// Quiet past quietWorkingHint but under half the (30s) idle timeout -> the
+	// plain cue, same as TestQuietGenerationHint's normal case.
+	m.lastStreamActivity = base.Add(-10 * time.Second)
+	got := m.quietGenerationHint()
+	if !strings.Contains(got, "still generating") {
+		t.Fatalf("under half the idle timeout: want the plain cue, got %q", got)
+	}
+	if strings.Contains(got, "auto-recover") {
+		t.Fatalf("under half the idle timeout: should not have escalated yet, got %q", got)
+	}
+
+	// Quiet for >= half the idle timeout -> escalates to name the watchdog and
+	// its ceiling (idleTimeout * providerio.StreamContentStallFactor = 1m00s here).
+	m.lastStreamActivity = base.Add(-15 * time.Second)
+	got = m.quietGenerationHint()
+	if !strings.Contains(got, "unusually quiet") || !strings.Contains(got, "auto-recover") {
+		t.Fatalf("past half the idle timeout: want an escalated cue naming the watchdog, got %q", got)
+	}
+	if !strings.Contains(got, "1m00s") {
+		t.Fatalf("escalated cue should name the content-stall ceiling (idleTimeout * StreamContentStallFactor = 1m00s), got %q", got)
+	}
+}
+
 // TestQuietHintHiddenWhenSidebarShowsIt: when the context sidebar is up (it
 // carries the "generating…" pulse in ACTIVITY), the working line must NOT also
 // show the hint — it appears in exactly one place.