From b8d76361bf473c93397186d28e4b16467089a57f Mon Sep 17 00:00:00 2001
From: Victor Vogel <satsdev@only21mil.xyz>
Date: Thu, 22 Oct 2026 12:31:08 -0500
Subject: [PATCH 1/9] fix(pi): stop offering extension-only models for text
 generation

Text generation runs Pi with --no-extensions, so models that a Pi
extension or package registers fail at set_model. Discovery now also
lists models with that launch and marks the rest as unusable for text
generation, and the text generation pickers leave them out.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 .../components/settings/SettingsPanels.tsx    |  5 +-
 .../settings/SourceControlWritingSettings.tsx |  5 +-
 apps/web/src/modelSelection.ts                | 19 +++++-
 packages/contracts/src/server.ts              |  3 +
 .../provider-pi/src/server/status.test.ts     | 65 +++++++++++++++----
 packages/provider-pi/src/server/status.ts     | 47 +++++++++++++-
 6 files changed, 120 insertions(+), 24 deletions(-)

diff --git a/apps/web/src/components/settings/SettingsPanels.tsx b/apps/web/src/components/settings/SettingsPanels.tsx
index 16c6ff3fb892..db4d46ec4898 100644
--- a/apps/web/src/components/settings/SettingsPanels.tsx
+++ b/apps/web/src/components/settings/SettingsPanels.tsx
@@ -93,6 +93,7 @@ import { useThreadActions } from "../../hooks/useThreadActions";
 import { useDesktopUpdateState } from "../../state/desktopUpdate";
 import {
   getCustomModelOptionsByInstance,
+  getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
 } from "../../modelSelection";
@@ -2107,9 +2108,7 @@ export function GeneralSettingsPanel() {
       (target) => target.serverConfig?.environment.capabilities.threadRestartContinuation === true,
     );
 
-  const textGenerationProviders = serverProviders.filter(
-    (provider) => provider.supportsTextGeneration !== false,
-  );
+  const textGenerationProviders = getTextGenerationProviders(serverProviders);
   const textGenerationModelSelection = resolveAppModelSelectionState(
     settings,
     textGenerationProviders,
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
index 3c76207c4816..93cfb9cfa0e4 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
@@ -26,6 +26,7 @@ import {
 } from "../../providerInstances";
 import {
   getCustomModelOptionsByInstance,
+  getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
 } from "../../modelSelection";
@@ -107,9 +108,7 @@ export function SourceControlWritingSettingsSection() {
     style.mode !== defaults.mode ||
     style.customInstructions !== defaults.customInstructions;
 
-  const textGenerationProviders = serverProviders.filter(
-    (provider) => provider.supportsTextGeneration !== false,
-  );
+  const textGenerationProviders = getTextGenerationProviders(serverProviders);
   const instanceEntries = sortProviderInstanceEntries(
     applyProviderInstanceSettings(
       deriveProviderInstanceEntries(textGenerationProviders),
diff --git a/apps/web/src/modelSelection.ts b/apps/web/src/modelSelection.ts
index 0b57a6cbb46f..e770f38dfa8c 100644
--- a/apps/web/src/modelSelection.ts
+++ b/apps/web/src/modelSelection.ts
@@ -317,6 +317,21 @@ export function getCustomModelOptionsByInstance(
   return out;
 }
 
+/**
+ * Providers and models that application text generation can run. An absent
+ * `supportsTextGeneration` on either one means supported.
+ */
+export function getTextGenerationProviders(
+  providers: ReadonlyArray<ServerProvider>,
+): ReadonlyArray<ServerProvider> {
+  return providers
+    .filter((provider) => provider.supportsTextGeneration !== false)
+    .map((provider) => {
+      const models = provider.models.filter((model) => model.supportsTextGeneration !== false);
+      return models.length === provider.models.length ? provider : { ...provider, models };
+    });
+}
+
 export function selectsPlanAgent(options: ModelSelection["options"]): boolean {
   return options?.some((option) => option.id === "agent" && option.value === "plan") ?? false;
 }
@@ -329,9 +344,7 @@ export function resolveAppModelSelectionState(
     instanceId: DEFAULT_TEXT_GENERATION_INSTANCE_ID,
     model: DEFAULT_TEXT_GENERATION_MODEL,
   };
-  const supportedProviders = providers.filter(
-    (provider) => provider.supportsTextGeneration !== false,
-  );
+  const supportedProviders = getTextGenerationProviders(providers);
   const entries = deriveProviderInstanceEntries(supportedProviders);
   const selectedEntry = entries.find(
     (entry) => entry.instanceId === selection.instanceId && entry.enabled && entry.isAvailable,
diff --git a/packages/contracts/src/server.ts b/packages/contracts/src/server.ts
index c39a29d6fe77..d300f1c85398 100644
--- a/packages/contracts/src/server.ts
+++ b/packages/contracts/src/server.ts
@@ -81,6 +81,9 @@ export const ServerProviderModel = Schema.Struct({
   isCustom: Schema.Boolean,
   isDefault: Schema.optional(Schema.Boolean),
   isLegacy: Schema.optional(Schema.Boolean),
+  // False when the provider can run this model in sessions but not for
+  // application text generation. Absent means supported.
+  supportsTextGeneration: Schema.optional(Schema.Boolean),
   capabilities: Schema.NullOr(ModelCapabilities),
 });
 export type ServerProviderModel = typeof ServerProviderModel.Type;
diff --git a/packages/provider-pi/src/server/status.test.ts b/packages/provider-pi/src/server/status.test.ts
index d4368a5a82e4..456865112ad8 100644
--- a/packages/provider-pi/src/server/status.test.ts
+++ b/packages/provider-pi/src/server/status.test.ts
@@ -54,7 +54,7 @@ function piProbeSpawner(version: string) {
   });
 }
 
-const piDiscoverySpawner = (
+const piRpcProcess = (
   inventory: unknown,
   slowStartup?: {
     readonly delay: Duration.Input;
@@ -93,22 +93,33 @@ const piDiscoverySpawner = (
         }
       }),
     );
-    return ChildProcessSpawner.make((command) => {
-      const args = ChildProcess.isStandardCommand(command) ? command.args : [];
-      return Effect.succeed(
-        args.includes("--version")
-          ? processHandle({ stdout: "pi 0.84.3\n" })
-          : ChildProcessSpawner.makeHandle({
-              ...processHandle({}),
-              exitCode: Effect.never,
-              isRunning: Effect.succeed(true),
-              stdin,
-              stdout: Stream.fromQueue(stdout),
-            }),
-      );
+    return ChildProcessSpawner.makeHandle({
+      ...processHandle({}),
+      exitCode: Effect.never,
+      isRunning: Effect.succeed(true),
+      stdin,
+      stdout: Stream.fromQueue(stdout),
     });
   });
 
+// Text generation lists models with --no-extensions, so its inventory can differ.
+const piDiscoverySpawner = (
+  inventory: unknown,
+  slowStartup?: Parameters<typeof piRpcProcess>[1],
+  extensionFreeInventory: unknown = inventory,
+) =>
+  Effect.succeed(
+    ChildProcessSpawner.make((command) => {
+      const args = ChildProcess.isStandardCommand(command) ? command.args : [];
+      return args.includes("--version")
+        ? Effect.succeed(processHandle({ stdout: "pi 0.84.3\n" }))
+        : piRpcProcess(
+            args.includes("--no-extensions") ? extensionFreeInventory : inventory,
+            slowStartup,
+          );
+    }),
+  );
+
 const settings = {
   enabled: true,
   binaryPath: "pi",
@@ -158,6 +169,32 @@ describe("PiProvider", () => {
     }).pipe(Effect.provide(NodeServices.layer)),
   );
 
+  it.effect("marks models that only load with Pi extensions as unusable for text generation", () =>
+    Effect.gen(function* () {
+      const spawner = yield* piDiscoverySpawner(
+        {
+          models: [
+            { provider: "anthropic", id: "claude-sonnet-4" },
+            { provider: "demo", id: "demo-model" },
+          ],
+        },
+        undefined,
+        { models: [{ provider: "anthropic", id: "claude-sonnet-4" }] },
+      );
+      const snapshot = yield* checkPiProviderStatus(settings).pipe(
+        Effect.provideService(ChildProcessSpawner.ChildProcessSpawner, spawner),
+      );
+      assert.deepEqual(
+        snapshot.models.map((model) => [model.slug, model.supportsTextGeneration]),
+        [
+          ["default", undefined],
+          ["anthropic/claude-sonnet-4", undefined],
+          ["demo/demo-model", false],
+        ],
+      );
+    }).pipe(Effect.provide(NodeServices.layer)),
+  );
+
   it.effect.each([
     ["missing models", {}],
     ["non-array models", { models: {} }],
diff --git a/packages/provider-pi/src/server/status.ts b/packages/provider-pi/src/server/status.ts
index 3030200c245a..183bc27c4aad 100644
--- a/packages/provider-pi/src/server/status.ts
+++ b/packages/provider-pi/src/server/status.ts
@@ -11,6 +11,7 @@ import * as DateTime from "effect/DateTime";
 import * as Effect from "effect/Effect";
 import * as Stream from "effect/Stream";
 import * as Exit from "effect/Exit";
+import * as Fiber from "effect/Fiber";
 import * as Option from "effect/Option";
 import * as Result from "effect/Result";
 import * as HttpClient from "effect/http/HttpClient";
@@ -134,6 +135,7 @@ const makePiDiscoveryConnection = Effect.fnUntraced(function* (
   environment: NodeJS.ProcessEnv,
   launchArgs: ReadonlyArray<string>,
   cwd?: string,
+  textGenerationLaunch = false,
 ) {
   const launch = buildPiRpcLaunch({
     launchArgs,
@@ -141,6 +143,8 @@ const makePiDiscoveryConnection = Effect.fnUntraced(function* (
     mcpSession: undefined,
     extensionPath: undefined,
     ephemeral: true,
+    disableExtensions: textGenerationLaunch,
+    disableTools: textGenerationLaunch,
   });
   const connection = yield* makePiRpcConnection({
     command: piSettings.binaryPath || "pi",
@@ -156,12 +160,45 @@ const makePiDiscoveryConnection = Effect.fnUntraced(function* (
   return connection;
 });
 
+// Text generation runs Pi with --no-extensions, so it cannot load models that an
+// extension or package registers. Listing models with that launch tells them apart.
+const discoverPiTextGenerationModelSlugs = Effect.fn(
+  "PiProviderStatus.discoverPiTextGenerationModelSlugs",
+)(function* (
+  piSettings: PiSettings,
+  environment: NodeJS.ProcessEnv,
+  launchArgs: ReadonlyArray<string>,
+  cwd?: string,
+) {
+  const connection = yield* makePiDiscoveryConnection(
+    piSettings,
+    environment,
+    launchArgs,
+    cwd,
+    true,
+  );
+  const modelsData = yield* connection.request({ type: "get_available_models" });
+  const models = yield* Effect.fromResult(parseDiscoveredModels(modelsData, undefined));
+  return new Set(models.map((model) => model.slug));
+}, Effect.scoped);
+
 const discoverPiViaRpc = Effect.fn("PiProviderStatus.discoverPiViaRpc")(function* (
   piSettings: PiSettings,
   environment: NodeJS.ProcessEnv,
   launchArgs: ReadonlyArray<string>,
   cwd?: string,
 ) {
+  // Without this list every model stays offered, and text generation still
+  // explains a rejected extension model.
+  const textGenerationModelSlugsFiber = yield* discoverPiTextGenerationModelSlugs(
+    piSettings,
+    environment,
+    launchArgs,
+    cwd,
+  ).pipe(
+    Effect.orElseSucceed(() => undefined),
+    Effect.forkScoped,
+  );
   const connection = yield* makePiDiscoveryConnection(piSettings, environment, launchArgs, cwd);
   const stateData = yield* connection.request({ type: "get_state" });
   const modelsData = yield* connection.request({ type: "get_available_models" });
@@ -170,8 +207,16 @@ const discoverPiViaRpc = Effect.fn("PiProviderStatus.discoverPiViaRpc")(function
     .pipe(Effect.orElseSucceed(() => undefined));
   const discoveredModels = yield* Effect.fromResult(parseDiscoveredModels(modelsData, stateData));
   const { slashCommands, skills } = parsePiDiscoveredCommands(commandsData);
+  const textGenerationModelSlugs = yield* Fiber.join(textGenerationModelSlugsFiber);
   return {
-    models: discoveredModels,
+    models:
+      textGenerationModelSlugs === undefined
+        ? discoveredModels
+        : discoveredModels.map((model) =>
+            textGenerationModelSlugs.has(model.slug)
+              ? model
+              : { ...model, supportsTextGeneration: false },
+          ),
     slashCommands: withPiBuiltinSlashCommands(slashCommands),
     skills,
     authenticated: discoveredModels.length > 0,

From 1174f26bd2d49044b900f6d3dc84951c62f8dbf2 Mon Sep 17 00:00:00 2001
From: Victor Vogel <satsdev@only21mil.xyz>
Date: Thu, 22 Oct 2026 15:48:14 -0500
Subject: [PATCH 2/9] fix(pi): preserve discovery and exclude customized
 extension models

Co-Authored-By: GPT-6.1 Sol <noreply@openai.com>
---
 .../components/settings/SettingsPanels.tsx    |  4 +-
 .../settings/SourceControlWritingSettings.tsx |  6 +-
 apps/web/src/modelSelection.test.ts           | 77 +++++++++++++++++++
 apps/web/src/modelSelection.ts                | 57 +++++++++-----
 .../provider-pi/src/server/status.test.ts     | 31 ++++++++
 packages/provider-pi/src/server/status.ts     |  9 ++-
 6 files changed, 159 insertions(+), 25 deletions(-)

diff --git a/apps/web/src/components/settings/SettingsPanels.tsx b/apps/web/src/components/settings/SettingsPanels.tsx
index b915fce6f81e..6156761f7eba 100644
--- a/apps/web/src/components/settings/SettingsPanels.tsx
+++ b/apps/web/src/components/settings/SettingsPanels.tsx
@@ -54,7 +54,7 @@ import { useSettingsScope } from "./SettingsScopeContext";
 import { ProjectDefaultsSettings } from "./ProjectDefaultsSettings";
 import { useDesktopUpdateState } from "../../state/desktopUpdate";
 import {
-  getCustomModelOptionsByInstance,
+  getTextGenerationModelOptionsByInstance,
   getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
@@ -836,7 +836,7 @@ export function GeneralSettingsPanel() {
   );
   const textGenProvider: ProviderDriverKind =
     textGenInstanceEntry?.driverKind ?? DEFAULT_DRIVER_KIND;
-  const textGenerationModelOptionsByInstance = getCustomModelOptionsByInstance(
+  const textGenerationModelOptionsByInstance = getTextGenerationModelOptionsByInstance(
     settings,
     textGenerationProviders,
     textGenInstanceId,
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
index f7d091287771..1f1958c588fc 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
@@ -25,7 +25,7 @@ import {
   sortProviderInstanceEntries,
 } from "../../providerInstances";
 import {
-  getCustomModelOptionsByInstance,
+  getTextGenerationModelOptionsByInstance,
   getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
@@ -144,7 +144,7 @@ export function SourceControlWritingSettingsSection() {
     (entry) =>
       entry.instanceId === defaultModelSelection.instanceId && entry.enabled && entry.isAvailable,
   );
-  const modelOptionsByInstance = getCustomModelOptionsByInstance(
+  const modelOptionsByInstance = getTextGenerationModelOptionsByInstance(
     settings,
     projectEffectiveTextGenerationProviders,
     activeSelection.instanceId,
@@ -166,7 +166,7 @@ export function SourceControlWritingSettingsSection() {
     },
     textGenerationProviders,
   );
-  const reviewGuideModelOptionsByInstance = getCustomModelOptionsByInstance(
+  const reviewGuideModelOptionsByInstance = getTextGenerationModelOptionsByInstance(
     settings,
     textGenerationProviders,
     reviewGuideSelection.instanceId,
diff --git a/apps/web/src/modelSelection.test.ts b/apps/web/src/modelSelection.test.ts
index 05a7e76b6b25..afee2d5654be 100644
--- a/apps/web/src/modelSelection.test.ts
+++ b/apps/web/src/modelSelection.test.ts
@@ -13,6 +13,9 @@ import { getComposerProviderState } from "./components/chat/composerProviderStat
 import { deriveProviderInstanceEntries, NO_PROVIDER_MODEL_SELECTION } from "./providerInstances";
 import {
   getAppModelOptionsForInstance,
+  getCustomModelOptionsByInstance,
+  getTextGenerationModelOptionsByInstance,
+  getTextGenerationProviders,
   resolveAppModelSelectionForInstance,
   resolveAppModelSelectionState,
   resolveEffectiveDefaultModelSelection,
@@ -670,6 +673,80 @@ describe("instance-scoped model selection", () => {
       NO_PROVIDER_MODEL_SELECTION,
     );
   });
+
+  it("does not select a model that the provider cannot use for text generation", () => {
+    const codex = provider({ instanceId: "codex", models: ["gpt-5.6-sol", "extension-model"] });
+    const providers = [
+      {
+        ...codex,
+        models: codex.models.map((m) =>
+          m.slug === "extension-model" ? { ...m, supportsTextGeneration: false } : m,
+        ),
+      },
+    ];
+    const settings: UnifiedSettings = {
+      ...settingsWithProviderInstances(),
+      textGenerationModelSelection: createModelSelection(codex.instanceId, "extension-model"),
+    };
+
+    expect(resolveAppModelSelectionState(settings, providers)).toEqual(
+      createModelSelection(codex.instanceId, "gpt-5.6-sol"),
+    );
+  });
+
+  it("excludes customized extension models while preserving unknown custom and thread models", () => {
+    const pi = provider({
+      provider: ProviderDriverKind.make("pi"),
+      instanceId: "pi",
+      models: ["default", "demo/demo-model"],
+    });
+    const providers = [
+      {
+        ...pi,
+        models: pi.models.map((model) =>
+          model.slug === "demo/demo-model" ? { ...model, supportsTextGeneration: false } : model,
+        ),
+      },
+    ];
+    const settings: UnifiedSettings = {
+      ...DEFAULT_UNIFIED_SETTINGS,
+      providerInstances: {
+        [pi.instanceId]: {
+          driver: ProviderDriverKind.make("pi"),
+          config: {
+            customModels: [
+              { slug: "demo/demo-model", name: "My extension model" },
+              { slug: "unknown/model", name: "My custom model" },
+            ],
+          },
+        },
+      },
+      textGenerationModelSelection: createModelSelection(pi.instanceId, "demo/demo-model"),
+    };
+    const supported = getTextGenerationProviders(providers);
+    expect(
+      getTextGenerationModelOptionsByInstance(settings, supported, pi.instanceId, "demo/demo-model")
+        .get(pi.instanceId)
+        ?.map((option) => option.slug),
+    ).toEqual(["default", "unknown/model"]);
+    expect(resolveAppModelSelectionState(settings, supported)).toEqual(
+      createModelSelection(pi.instanceId, "default"),
+    );
+    expect(
+      resolveAppModelSelectionState(
+        {
+          ...settings,
+          textGenerationModelSelection: createModelSelection(pi.instanceId, "unknown/model"),
+        },
+        supported,
+      ).model,
+    ).toBe("unknown/model");
+    expect(
+      getCustomModelOptionsByInstance(settings, providers)
+        .get(pi.instanceId)
+        ?.map((option) => option.slug),
+    ).toEqual(["default", "demo/demo-model", "unknown/model"]);
+  });
 });
 
 describe("resolveAppModelSelectionState with the opencode plan agent", () => {
diff --git a/apps/web/src/modelSelection.ts b/apps/web/src/modelSelection.ts
index e770f38dfa8c..c6d6d3642814 100644
--- a/apps/web/src/modelSelection.ts
+++ b/apps/web/src/modelSelection.ts
@@ -317,19 +317,45 @@ export function getCustomModelOptionsByInstance(
   return out;
 }
 
-/**
- * Providers and models that application text generation can run. An absent
- * `supportsTextGeneration` on either one means supported.
- */
+/** An absent `supportsTextGeneration` means supported. */
 export function getTextGenerationProviders(
   providers: ReadonlyArray<ServerProvider>,
 ): ReadonlyArray<ServerProvider> {
-  return providers
-    .filter((provider) => provider.supportsTextGeneration !== false)
-    .map((provider) => {
-      const models = provider.models.filter((model) => model.supportsTextGeneration !== false);
-      return models.length === provider.models.length ? provider : { ...provider, models };
-    });
+  return providers.filter((provider) => provider.supportsTextGeneration !== false);
+}
+
+function getTextGenerationModelOptionsForInstance(
+  settings: UnifiedSettings,
+  entry: ProviderInstanceEntry,
+  selectedModel?: string | null,
+): AppModelOption[] {
+  const unsupported = new Set(
+    entry.models
+      .filter((model) => model.supportsTextGeneration === false)
+      .map((model) => model.slug),
+  );
+  // Filter after custom entries are rebuilt so a display-name override cannot restore a model.
+  return getAppModelOptionsForInstance(settings, entry, selectedModel).filter(
+    (option) => !unsupported.has(option.slug),
+  );
+}
+
+export function getTextGenerationModelOptionsByInstance(
+  settings: UnifiedSettings,
+  providers: ReadonlyArray<ServerProvider>,
+  selectedInstanceId?: ProviderInstanceId | null,
+  selectedModel?: string | null,
+): ReadonlyMap<ProviderInstanceId, ReadonlyArray<ModelEsque>> {
+  return new Map(
+    deriveProviderInstanceEntries(getTextGenerationProviders(providers)).map((entry) => [
+      entry.instanceId,
+      getTextGenerationModelOptionsForInstance(
+        settings,
+        entry,
+        entry.instanceId === selectedInstanceId ? selectedModel : null,
+      ),
+    ]),
+  );
 }
 
 export function selectsPlanAgent(options: ModelSelection["options"]): boolean {
@@ -356,7 +382,7 @@ export function resolveAppModelSelectionState(
     // A saved model the catalog no longer lists, or a new fallback instance,
     // gets the driver's cheap text generation default. The catalog's own
     // default is the flagship chat model, which is too expensive here.
-    const options = getAppModelOptionsForInstance(settings, entry);
+    const options = getTextGenerationModelOptionsForInstance(settings, entry);
     const model =
       resolveSelectableModel(entry.driverKind, selectedModel, options) ??
       resolveSelectableModel(
@@ -364,13 +390,8 @@ export function resolveAppModelSelectionState(
         DEFAULT_TEXT_GENERATION_MODEL_BY_PROVIDER[entry.driverKind],
         options,
       ) ??
-      resolveAppModelSelectionForInstance(
-        entry.instanceId,
-        settings,
-        supportedProviders,
-        selectedModel,
-      ) ??
-      entry.models[0]?.slug ??
+      options.find((option) => option.isDefault)?.slug ??
+      options[0]?.slug ??
       DEFAULT_TEXT_GENERATION_MODEL_BY_PROVIDER[entry.driverKind];
     if (!model) {
       return createModelSelection(entry.instanceId, "", []);
diff --git a/packages/provider-pi/src/server/status.test.ts b/packages/provider-pi/src/server/status.test.ts
index 8f20d7e43193..d25560c2ea76 100644
--- a/packages/provider-pi/src/server/status.test.ts
+++ b/packages/provider-pi/src/server/status.test.ts
@@ -2,6 +2,8 @@ import * as NodeServices from "@effect/platform-node/NodeServices";
 import { assert, describe, it } from "@effect/vitest";
 import * as Cause from "effect/Cause";
 import * as Effect from "effect/Effect";
+import * as Fiber from "effect/Fiber";
+import * as TestClock from "effect/testing/TestClock";
 import * as Queue from "effect/Queue";
 import * as Schema from "effect/Schema";
 import * as Sink from "effect/Sink";
@@ -66,6 +68,7 @@ const piRpcProcess = (inventory: unknown) =>
           stdinBuffer = stdinBuffer.slice(newline + 1);
           if (line.length === 0) continue;
           const request = decodeRpcRequest(line);
+          if (request.type === "get_available_models" && inventory === null) continue;
           const data =
             request.type === "get_available_models"
               ? inventory
@@ -175,6 +178,34 @@ describe("PiProvider", () => {
     }).pipe(Effect.provide(NodeServices.layer)),
   );
 
+  it.effect("preserves normal discovery when the extension-free model listing times out", () =>
+    Effect.gen(function* () {
+      const spawner = yield* piDiscoverySpawner(
+        { models: [{ provider: "demo", id: "demo-model" }] },
+        null,
+      );
+      const fiber = yield* checkPiProviderStatus(settings).pipe(
+        Effect.provideService(ChildProcessSpawner.ChildProcessSpawner, spawner),
+        Effect.forkChild,
+      );
+      yield* TestClock.adjust("30 seconds");
+      const snapshot = yield* Fiber.join(fiber);
+      assert.equal(snapshot.status, "ready");
+      assert.equal(snapshot.auth.status, "authenticated");
+      assert.deepEqual(
+        snapshot.models.map((model) => [model.slug, model.supportsTextGeneration]),
+        [
+          ["default", undefined],
+          ["demo/demo-model", undefined],
+        ],
+      );
+      assert.include(
+        snapshot.slashCommands.map((command) => command.name),
+        "compact",
+      );
+    }).pipe(Effect.provide(NodeServices.layer)),
+  );
+
   // regression: #18498 a malformed model inventory must not restore stale Pi models
   it.effect.each([
     ["missing models", {}],
diff --git a/packages/provider-pi/src/server/status.ts b/packages/provider-pi/src/server/status.ts
index 183bc27c4aad..6d6af1719a28 100644
--- a/packages/provider-pi/src/server/status.ts
+++ b/packages/provider-pi/src/server/status.ts
@@ -59,6 +59,7 @@ const PI_PRESENTATION = {
 
 const VERSION_PROBE_TIMEOUT_MS = 4_000;
 const PI_RPC_DISCOVERY_TIMEOUT_MS = 30_000;
+const PI_TEXT_GENERATION_DISCOVERY_TIMEOUT_MS = 5_000;
 /**
  * get_entries arrived in 0.80.3 and agent_settled landed in source at 0.80.4.
  * Version 0.80.5 was the first published package containing both hooks.
@@ -188,8 +189,8 @@ const discoverPiViaRpc = Effect.fn("PiProviderStatus.discoverPiViaRpc")(function
   launchArgs: ReadonlyArray<string>,
   cwd?: string,
 ) {
-  // Without this list every model stays offered, and text generation still
-  // explains a rejected extension model.
+  // This optional probe must finish before the normal discovery deadline so
+  // it cannot discard an otherwise usable catalog and authentication state.
   const textGenerationModelSlugsFiber = yield* discoverPiTextGenerationModelSlugs(
     piSettings,
     environment,
@@ -197,6 +198,10 @@ const discoverPiViaRpc = Effect.fn("PiProviderStatus.discoverPiViaRpc")(function
     cwd,
   ).pipe(
     Effect.orElseSucceed(() => undefined),
+    Effect.timeoutOrElse({
+      duration: PI_TEXT_GENERATION_DISCOVERY_TIMEOUT_MS,
+      orElse: () => Effect.succeed(undefined),
+    }),
     Effect.forkScoped,
   );
   const connection = yield* makePiDiscoveryConnection(piSettings, environment, launchArgs, cwd);

From eda6e3569a62eb45a1352b364e6cdc43e0d00b71 Mon Sep 17 00:00:00 2001
From: Victor Vogel <satsdev@only21mil.xyz>
Date: Thu, 22 Oct 2026 15:54:14 -0500
Subject: [PATCH 3/9] test(pi): synchronize discovery timeout with the pending
 request

Co-Authored-By: GPT-6.1 Sol <noreply@openai.com>
---
 .../provider-pi/src/server/status.test.ts     | 27 +++++++++++++++----
 1 file changed, 22 insertions(+), 5 deletions(-)

diff --git a/packages/provider-pi/src/server/status.test.ts b/packages/provider-pi/src/server/status.test.ts
index d25560c2ea76..c2c92627ff51 100644
--- a/packages/provider-pi/src/server/status.test.ts
+++ b/packages/provider-pi/src/server/status.test.ts
@@ -2,6 +2,7 @@ import * as NodeServices from "@effect/platform-node/NodeServices";
 import { assert, describe, it } from "@effect/vitest";
 import * as Cause from "effect/Cause";
 import * as Effect from "effect/Effect";
+import * as Deferred from "effect/Deferred";
 import * as Fiber from "effect/Fiber";
 import * as TestClock from "effect/testing/TestClock";
 import * as Queue from "effect/Queue";
@@ -54,7 +55,7 @@ function piProbeSpawner(version: string) {
   });
 }
 
-const piRpcProcess = (inventory: unknown) =>
+const piRpcProcess = (inventory: unknown, onModelRequest: Effect.Effect<void> = Effect.void) =>
   Effect.gen(function* () {
     const stdout = yield* Queue.unbounded<Uint8Array, Cause.Done>();
     let stdinBuffer = "";
@@ -68,7 +69,10 @@ const piRpcProcess = (inventory: unknown) =>
           stdinBuffer = stdinBuffer.slice(newline + 1);
           if (line.length === 0) continue;
           const request = decodeRpcRequest(line);
-          if (request.type === "get_available_models" && inventory === null) continue;
+          if (request.type === "get_available_models") {
+            yield* onModelRequest;
+            if (inventory === null) continue;
+          }
           const data =
             request.type === "get_available_models"
               ? inventory
@@ -94,13 +98,20 @@ const piRpcProcess = (inventory: unknown) =>
   });
 
 // Text generation lists models with --no-extensions, so its inventory can differ.
-const piDiscoverySpawner = (inventory: unknown, extensionFreeInventory: unknown = inventory) =>
+const piDiscoverySpawner = (
+  inventory: unknown,
+  extensionFreeInventory: unknown = inventory,
+  onExtensionFreeModelRequest: Effect.Effect<void> = Effect.void,
+) =>
   Effect.succeed(
     ChildProcessSpawner.make((command) => {
       const args = ChildProcess.isStandardCommand(command) ? command.args : [];
       return args.includes("--version")
         ? Effect.succeed(processHandle({ stdout: "pi 0.84.3\n" }))
-        : piRpcProcess(args.includes("--no-extensions") ? extensionFreeInventory : inventory);
+        : piRpcProcess(
+            args.includes("--no-extensions") ? extensionFreeInventory : inventory,
+            args.includes("--no-extensions") ? onExtensionFreeModelRequest : Effect.void,
+          );
     }),
   );
 
@@ -180,15 +191,21 @@ describe("PiProvider", () => {
 
   it.effect("preserves normal discovery when the extension-free model listing times out", () =>
     Effect.gen(function* () {
+      const modelRequested = yield* Deferred.make<void>();
+      const completed = yield* Deferred.make<void>();
       const spawner = yield* piDiscoverySpawner(
         { models: [{ provider: "demo", id: "demo-model" }] },
         null,
+        Deferred.succeed(modelRequested, undefined).pipe(Effect.asVoid),
       );
       const fiber = yield* checkPiProviderStatus(settings).pipe(
         Effect.provideService(ChildProcessSpawner.ChildProcessSpawner, spawner),
+        Effect.tap(() => Deferred.succeed(completed, undefined)),
         Effect.forkChild,
       );
-      yield* TestClock.adjust("30 seconds");
+      yield* Deferred.await(modelRequested);
+      yield* TestClock.adjust("5 seconds");
+      assert.isTrue(yield* Deferred.isDone(completed));
       const snapshot = yield* Fiber.join(fiber);
       assert.equal(snapshot.status, "ready");
       assert.equal(snapshot.auth.status, "authenticated");

From 6c9d66fc3d2b66c31df91877178bc01a4ccc25e8 Mon Sep 17 00:00:00 2001
From: Victor Vogel <satsdev@only21mil.xyz>
Date: Thu, 22 Oct 2026 15:55:42 -0500
Subject: [PATCH 4/9] test(pi): advance optional and normal discovery deadlines
 separately

Co-Authored-By: GPT-6.1 Sol <noreply@openai.com>
---
 packages/provider-pi/src/server/status.test.ts | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/packages/provider-pi/src/server/status.test.ts b/packages/provider-pi/src/server/status.test.ts
index c2c92627ff51..55008ebeb9da 100644
--- a/packages/provider-pi/src/server/status.test.ts
+++ b/packages/provider-pi/src/server/status.test.ts
@@ -192,7 +192,6 @@ describe("PiProvider", () => {
   it.effect("preserves normal discovery when the extension-free model listing times out", () =>
     Effect.gen(function* () {
       const modelRequested = yield* Deferred.make<void>();
-      const completed = yield* Deferred.make<void>();
       const spawner = yield* piDiscoverySpawner(
         { models: [{ provider: "demo", id: "demo-model" }] },
         null,
@@ -200,12 +199,11 @@ describe("PiProvider", () => {
       );
       const fiber = yield* checkPiProviderStatus(settings).pipe(
         Effect.provideService(ChildProcessSpawner.ChildProcessSpawner, spawner),
-        Effect.tap(() => Deferred.succeed(completed, undefined)),
         Effect.forkChild,
       );
       yield* Deferred.await(modelRequested);
       yield* TestClock.adjust("5 seconds");
-      assert.isTrue(yield* Deferred.isDone(completed));
+      yield* TestClock.adjust("25 seconds");
       const snapshot = yield* Fiber.join(fiber);
       assert.equal(snapshot.status, "ready");
       assert.equal(snapshot.auth.status, "authenticated");

From 09631f3fd1de7240758152fe3b731580ea29adae Mon Sep 17 00:00:00 2001
From: Victor Vogel <satsdev@only21mil.xyz>
Date: Fri, 23 Oct 2026 06:13:45 -0500
Subject: [PATCH 5/9] fix(pi): fall back to a usable catalog model when all
 options are hidden

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 apps/web/src/modelSelection.ts            | 1 +
 packages/provider-pi/src/server/status.ts | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/apps/web/src/modelSelection.ts b/apps/web/src/modelSelection.ts
index c6d6d3642814..5916447c213b 100644
--- a/apps/web/src/modelSelection.ts
+++ b/apps/web/src/modelSelection.ts
@@ -392,6 +392,7 @@ export function resolveAppModelSelectionState(
       ) ??
       options.find((option) => option.isDefault)?.slug ??
       options[0]?.slug ??
+      entry.models.find((model) => model.supportsTextGeneration !== false)?.slug ??
       DEFAULT_TEXT_GENERATION_MODEL_BY_PROVIDER[entry.driverKind];
     if (!model) {
       return createModelSelection(entry.instanceId, "", []);
diff --git a/packages/provider-pi/src/server/status.ts b/packages/provider-pi/src/server/status.ts
index 6d6af1719a28..f05cf6308769 100644
--- a/packages/provider-pi/src/server/status.ts
+++ b/packages/provider-pi/src/server/status.ts
@@ -200,7 +200,7 @@ const discoverPiViaRpc = Effect.fn("PiProviderStatus.discoverPiViaRpc")(function
     Effect.orElseSucceed(() => undefined),
     Effect.timeoutOrElse({
       duration: PI_TEXT_GENERATION_DISCOVERY_TIMEOUT_MS,
-      orElse: () => Effect.succeed(undefined),
+      orElse: () => Effect.void,
     }),
     Effect.forkScoped,
   );

From 9c79d177bc00550385142977fd9047bbdaa6df51 Mon Sep 17 00:00:00 2001
From: maria-rcks <maria@kuuro.net>
Date: Mon, 26 Oct 2026 12:12:17 +0000
Subject: [PATCH 6/9] refactor(pi): keep model filtering scoped and tighten
 timeout coverage

---
 .../src/components/settings/SettingsPanels.tsx    |  5 +++--
 .../settings/SourceControlWritingSettings.tsx     |  5 +++--
 apps/web/src/modelSelection.test.ts               |  3 +--
 apps/web/src/modelSelection.ts                    | 15 ++++++---------
 packages/provider-pi/src/server/status.test.ts    |  1 -
 5 files changed, 13 insertions(+), 16 deletions(-)

diff --git a/apps/web/src/components/settings/SettingsPanels.tsx b/apps/web/src/components/settings/SettingsPanels.tsx
index 05b63ca97acc..92be5a4c404a 100644
--- a/apps/web/src/components/settings/SettingsPanels.tsx
+++ b/apps/web/src/components/settings/SettingsPanels.tsx
@@ -58,7 +58,6 @@ import { ThreadTitleInstructionsSettings } from "./ThreadTitleInstructionsSettin
 import { useDesktopUpdateState } from "../../state/desktopUpdate";
 import {
   getTextGenerationModelOptionsByInstance,
-  getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
 } from "../../modelSelection";
@@ -815,7 +814,9 @@ export function GeneralSettingsPanel() {
       (target) => target.serverConfig?.environment.capabilities.threadRestartContinuation === true,
     );
 
-  const textGenerationProviders = getTextGenerationProviders(serverProviders);
+  const textGenerationProviders = serverProviders.filter(
+    (provider) => provider.supportsTextGeneration !== false,
+  );
   const textGenerationModelSelection = resolveAppModelSelectionState(
     settings,
     textGenerationProviders,
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
index 1f1958c588fc..401e33a89c5e 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
@@ -26,7 +26,6 @@ import {
 } from "../../providerInstances";
 import {
   getTextGenerationModelOptionsByInstance,
-  getTextGenerationProviders,
   resolveAppModelSelectionState,
   selectsPlanAgent,
 } from "../../modelSelection";
@@ -108,7 +107,9 @@ export function SourceControlWritingSettingsSection() {
     style.mode !== defaults.mode ||
     style.customInstructions !== defaults.customInstructions;
 
-  const textGenerationProviders = getTextGenerationProviders(serverProviders);
+  const textGenerationProviders = serverProviders.filter(
+    (provider) => provider.supportsTextGeneration !== false,
+  );
   const instanceEntries = sortProviderInstanceEntries(
     applyProviderInstanceSettings(
       deriveProviderInstanceEntries(textGenerationProviders),
diff --git a/apps/web/src/modelSelection.test.ts b/apps/web/src/modelSelection.test.ts
index afee2d5654be..00b333f46899 100644
--- a/apps/web/src/modelSelection.test.ts
+++ b/apps/web/src/modelSelection.test.ts
@@ -15,7 +15,6 @@ import {
   getAppModelOptionsForInstance,
   getCustomModelOptionsByInstance,
   getTextGenerationModelOptionsByInstance,
-  getTextGenerationProviders,
   resolveAppModelSelectionForInstance,
   resolveAppModelSelectionState,
   resolveEffectiveDefaultModelSelection,
@@ -723,7 +722,7 @@ describe("instance-scoped model selection", () => {
       },
       textGenerationModelSelection: createModelSelection(pi.instanceId, "demo/demo-model"),
     };
-    const supported = getTextGenerationProviders(providers);
+    const supported = providers.filter((provider) => provider.supportsTextGeneration !== false);
     expect(
       getTextGenerationModelOptionsByInstance(settings, supported, pi.instanceId, "demo/demo-model")
         .get(pi.instanceId)
diff --git a/apps/web/src/modelSelection.ts b/apps/web/src/modelSelection.ts
index cd83eed59601..e3f8781260d3 100644
--- a/apps/web/src/modelSelection.ts
+++ b/apps/web/src/modelSelection.ts
@@ -311,13 +311,6 @@ export function getCustomModelOptionsByInstance(
   return out;
 }
 
-/** An absent `supportsTextGeneration` means supported. */
-export function getTextGenerationProviders(
-  providers: ReadonlyArray<ServerProvider>,
-): ReadonlyArray<ServerProvider> {
-  return providers.filter((provider) => provider.supportsTextGeneration !== false);
-}
-
 function getTextGenerationModelOptionsForInstance(
   settings: UnifiedSettings,
   entry: ProviderInstanceEntry,
@@ -341,7 +334,9 @@ export function getTextGenerationModelOptionsByInstance(
   selectedModel?: string | null,
 ): ReadonlyMap<ProviderInstanceId, ReadonlyArray<ModelEsque>> {
   return new Map(
-    deriveProviderInstanceEntries(getTextGenerationProviders(providers)).map((entry) => [
+    deriveProviderInstanceEntries(
+      providers.filter((provider) => provider.supportsTextGeneration !== false),
+    ).map((entry) => [
       entry.instanceId,
       getTextGenerationModelOptionsForInstance(
         settings,
@@ -364,7 +359,9 @@ export function resolveAppModelSelectionState(
     instanceId: DEFAULT_TEXT_GENERATION_INSTANCE_ID,
     model: DEFAULT_TEXT_GENERATION_MODEL,
   };
-  const supportedProviders = getTextGenerationProviders(providers);
+  const supportedProviders = providers.filter(
+    (provider) => provider.supportsTextGeneration !== false,
+  );
   const entries = deriveProviderInstanceEntries(supportedProviders);
   const selectedEntry = entries.find(
     (entry) => entry.instanceId === selection.instanceId && entry.enabled && entry.isAvailable,
diff --git a/packages/provider-pi/src/server/status.test.ts b/packages/provider-pi/src/server/status.test.ts
index 55008ebeb9da..50d911f3631b 100644
--- a/packages/provider-pi/src/server/status.test.ts
+++ b/packages/provider-pi/src/server/status.test.ts
@@ -203,7 +203,6 @@ describe("PiProvider", () => {
       );
       yield* Deferred.await(modelRequested);
       yield* TestClock.adjust("5 seconds");
-      yield* TestClock.adjust("25 seconds");
       const snapshot = yield* Fiber.join(fiber);
       assert.equal(snapshot.status, "ready");
       assert.equal(snapshot.auth.status, "authenticated");

From 356cd0b93e2a3278fb6833aa46b030967e1a84fd Mon Sep 17 00:00:00 2001
From: maria-rcks <maria@kuuro.net>
Date: Mon, 26 Oct 2026 12:20:03 +0000
Subject: [PATCH 7/9] fix(web): validate text models across selected
 environments

---
 ...rceControlWritingSettings.browser.test.tsx | 77 ++++++++++++++++++-
 .../settings/useScopedModelAvailability.ts    |  4 +-
 2 files changed, 76 insertions(+), 5 deletions(-)

diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
index 850b7ea016c7..c46a1692612d 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
@@ -1,5 +1,13 @@
 import { render } from "../../../test/render";
 import { DEFAULT_UNIFIED_SETTINGS } from "@t3tools/contracts/settings";
+import {
+  EnvironmentId,
+  ProviderDriverKind,
+  ProviderInstanceId,
+  type ServerProvider,
+} from "@t3tools/contracts";
+import { useScopedModelDisabledReason } from "./useScopedModelAvailability";
+import { deriveProviderInstanceEntries } from "../../providerInstances";
 import { StrictMode, type ReactNode } from "react";
 import { describe, expect, it, vi } from "vite-plus/test";
 import { page, userEvent } from "vite-plus/test/browser";
@@ -10,6 +18,8 @@ import type { ScopedSettingsPatch } from "./scopedSettings";
 type WritingStyle = typeof DEFAULT_UNIFIED_SETTINGS.sourceControlWritingStyle;
 const state = vi.hoisted(() => ({
   styles: [] as WritingStyle[],
+  providerInstances: {} as typeof DEFAULT_UNIFIED_SETTINGS.providerInstances,
+  providers: new Map<EnvironmentId, readonly ServerProvider[]>(),
   updateSettings: vi.fn<(patch: ScopedSettingsPatch) => void>(),
 }));
 
@@ -34,15 +44,27 @@ vi.mock(import("./SettingsScopeContext"), async (original) => ({
     scope: { kind: "all", environmentIds: [] },
     environment: null,
     connectedEnvironments: [],
-    targets: state.styles.map((style) => ({
-      settings: { ...DEFAULT_UNIFIED_SETTINGS, sourceControlWritingStyle: style },
+    targets: state.styles.map((style, index) => ({
+      environmentId: EnvironmentId.make(`environment-${index}`),
+      settings: {
+        ...DEFAULT_UNIFIED_SETTINGS,
+        providerInstances: state.providerInstances,
+        sourceControlWritingStyle: style,
+      },
     })),
     target: null,
   })) as never,
 }));
 vi.mock(import("../../state/environments"), async (original) => ({
   ...(await original()),
-  useEnvironmentProviders: () => new Map(),
+  useEnvironmentProviders: () => state.providers,
+  useEnvironments: (() => ({
+    environments: [...state.providers.keys()].map((environmentId) => ({
+      environmentId,
+      label: environmentId,
+      serverConfig: {},
+    })),
+  })) as never,
 }));
 vi.mock(import("./settingsLayout"), async (original) => ({
   ...(await original()),
@@ -69,6 +91,8 @@ const content = () => (
 );
 
 async function setup() {
+  state.providers = new Map();
+  state.providerInstances = {};
   state.styles = [
     {
       ...DEFAULT_UNIFIED_SETTINGS.sourceControlWritingStyle,
@@ -111,3 +135,50 @@ describe("mixed source control instructions", () => {
     ).toEqual(initialInstructions);
   });
 });
+
+it("rejects a scoped model when another environment requires extensions for it", async () => {
+  state.styles = [DEFAULT_UNIFIED_SETTINGS.sourceControlWritingStyle];
+  const instanceId = ProviderInstanceId.make("pi");
+  state.providerInstances = {
+    [instanceId]: { driver: ProviderDriverKind.make("pi"), enabled: true },
+  };
+  const provider: ServerProvider = {
+    instanceId,
+    driver: ProviderDriverKind.make("pi"),
+    enabled: true,
+    installed: true,
+    version: null,
+    status: "ready",
+    auth: { status: "authenticated" },
+    checkedAt: "2026-01-01T00:00:00.000Z",
+    slashCommands: [],
+    skills: [],
+    models: [{ slug: "demo/model", name: "Demo", isCustom: false, capabilities: {} }],
+  };
+  state.providers = new Map([
+    [
+      EnvironmentId.make("environment-0"),
+      [
+        {
+          ...provider,
+          models: provider.models.map((model) => ({ ...model, supportsTextGeneration: false })),
+        },
+      ],
+    ],
+  ]);
+  function Availability() {
+    const reason = useScopedModelDisabledReason(
+      { ...DEFAULT_UNIFIED_SETTINGS, providerInstances: state.providerInstances },
+      deriveProviderInstanceEntries([provider]),
+    );
+    return <p>{reason(instanceId, "demo/model") ?? "Available"}</p>;
+  }
+  await using screen = await render(<Availability />);
+  await expect
+    .element(
+      screen.getByText(
+        "This model is unavailable on environment-0. Select that environment to choose its model separately.",
+      ),
+    )
+    .toBeVisible();
+});
diff --git a/apps/web/src/components/settings/useScopedModelAvailability.ts b/apps/web/src/components/settings/useScopedModelAvailability.ts
index abf1e1e1afc0..58ca41b51b33 100644
--- a/apps/web/src/components/settings/useScopedModelAvailability.ts
+++ b/apps/web/src/components/settings/useScopedModelAvailability.ts
@@ -1,7 +1,7 @@
 import type { ProviderInstanceId, UnifiedSettings } from "@t3tools/contracts";
 
 import { mergeEnvironmentSettings } from "../../hooks/useSettings";
-import { getCustomModelOptionsByInstance } from "../../modelSelection";
+import { getTextGenerationModelOptionsByInstance } from "../../modelSelection";
 import {
   applyProviderInstanceSettings,
   deriveProviderInstanceEntries,
@@ -30,7 +30,7 @@ export function useScopedModelDisabledReason(
         candidate.settings,
         candidate.projectId,
       ).find((option) => option.instanceId === instanceId);
-      const options = getCustomModelOptionsByInstance(
+      const options = getTextGenerationModelOptionsByInstance(
         mergeEnvironmentSettings(candidate.settings, settings),
         providers,
       ).get(instanceId);

From 0bab335b4f8cbe103dfa2e22786adc6df843a82b Mon Sep 17 00:00:00 2001
From: maria-rcks <maria@kuuro.net>
Date: Fri, 30 Oct 2026 14:08:30 +0000
Subject: [PATCH 8/9] fix(web): preserve extension models for thread defaults

---
 .../src/components/settings/SettingsPanels.tsx    |  1 +
 .../SourceControlWritingSettings.browser.test.tsx | 15 +++++++++++++--
 .../settings/SourceControlWritingSettings.tsx     |  2 +-
 .../settings/useScopedModelAvailability.ts        | 11 +++++++++--
 4 files changed, 24 insertions(+), 5 deletions(-)

diff --git a/apps/web/src/components/settings/SettingsPanels.tsx b/apps/web/src/components/settings/SettingsPanels.tsx
index 29d6ffbbef5e..7ea4d8ddc149 100644
--- a/apps/web/src/components/settings/SettingsPanels.tsx
+++ b/apps/web/src/components/settings/SettingsPanels.tsx
@@ -1529,6 +1529,7 @@ export function ThreadsSettingsPanel() {
   const textGenerationModelDisabledReason = useScopedModelDisabledReason(
     settings,
     textGenerationModelInstanceEntries,
+    true,
   );
   const mixedAddProjectBaseDirectory = useScopedSettingsMixed(["addProjectBaseDirectory"]);
   const mixedTextGenerationModel = useScopedSettingsMixed(["textGenerationModelSelection"]);
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
index 49661ee59405..86a8321520f9 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
@@ -168,13 +168,24 @@ it("rejects a scoped model when another environment requires extensions for it",
     ],
   ]);
   function Availability() {
-    const reason = useScopedModelDisabledReason(
+    const backgroundReason = useScopedModelDisabledReason(
       { ...DEFAULT_UNIFIED_SETTINGS, providerInstances: state.providerInstances },
       deriveProviderInstanceEntries([provider]),
+      true,
+    );
+    const threadReason = useScopedModelDisabledReason(
+      { ...DEFAULT_UNIFIED_SETTINGS, providerInstances: state.providerInstances },
+      deriveProviderInstanceEntries([provider]),
+    );
+    return (
+      <>
+        <p>{backgroundReason(instanceId, "demo/model") ?? "Available"}</p>
+        <p>{threadReason(instanceId, "demo/model") ?? "Available for threads"}</p>
+      </>
     );
-    return <p>{reason(instanceId, "demo/model") ?? "Available"}</p>;
   }
   await using screen = await render(<Availability />);
+  await expect.element(screen.getByText("Available for threads")).toBeVisible();
   await expect
     .element(
       screen.getByText(
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
index bc6dfc9d7352..b9885befb18d 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
@@ -145,7 +145,7 @@ export function SourceControlWritingSettingsSection() {
     activeSelection.instanceId,
     activeSelection.model,
   );
-  const writerModelDisabledReason = useScopedModelDisabledReason(settings, instanceEntries);
+  const writerModelDisabledReason = useScopedModelDisabledReason(settings, instanceEntries, true);
   const writerInstanceEntry = instanceEntries.find(
     (entry) => entry.instanceId === activeSelection.instanceId,
   );
diff --git a/apps/web/src/components/settings/useScopedModelAvailability.ts b/apps/web/src/components/settings/useScopedModelAvailability.ts
index 58ca41b51b33..9fa4eeb938b1 100644
--- a/apps/web/src/components/settings/useScopedModelAvailability.ts
+++ b/apps/web/src/components/settings/useScopedModelAvailability.ts
@@ -1,7 +1,10 @@
 import type { ProviderInstanceId, UnifiedSettings } from "@t3tools/contracts";
 
 import { mergeEnvironmentSettings } from "../../hooks/useSettings";
-import { getTextGenerationModelOptionsByInstance } from "../../modelSelection";
+import {
+  getCustomModelOptionsByInstance,
+  getTextGenerationModelOptionsByInstance,
+} from "../../modelSelection";
 import {
   applyProviderInstanceSettings,
   deriveProviderInstanceEntries,
@@ -13,6 +16,7 @@ import { useSettingsScope } from "./SettingsScopeContext";
 export function useScopedModelDisabledReason(
   settings: UnifiedSettings,
   entries: readonly ProviderInstanceEntry[],
+  textGeneration = false,
 ) {
   const { targets } = useSettingsScope();
   const { environments } = useEnvironments();
@@ -30,7 +34,10 @@ export function useScopedModelDisabledReason(
         candidate.settings,
         candidate.projectId,
       ).find((option) => option.instanceId === instanceId);
-      const options = getTextGenerationModelOptionsByInstance(
+      const optionsForInstance = textGeneration
+        ? getTextGenerationModelOptionsByInstance
+        : getCustomModelOptionsByInstance;
+      const options = optionsForInstance(
         mergeEnvironmentSettings(candidate.settings, settings),
         providers,
       ).get(instanceId);

From 12a5a9e250acafe86118208927aca1c21d31a777 Mon Sep 17 00:00:00 2001
From: maria-rcks <maria@kuuro.net>
Date: Fri, 30 Oct 2026 14:23:15 +0000
Subject: [PATCH 9/9] fix(web): guard scoped writer model enablement

---
 ...rceControlWritingSettings.browser.test.tsx | 35 +++++++++++++++++--
 .../settings/SourceControlWritingSettings.tsx | 20 +++++++++--
 2 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
index 86a8321520f9..d04e929f2f22 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.browser.test.tsx
@@ -32,6 +32,7 @@ vi.mock(import("./useScopedSettings"), async (original) => ({
   useScopedSettings: (() => ({
     ...DEFAULT_UNIFIED_SETTINGS,
     sourceControlWritingStyle: state.styles[0],
+    providerInstances: state.providerInstances,
   })) as never,
   useScopedSettingsMixed: (keys) =>
     !keys.includes("reviewGuidesEnabled") &&
@@ -42,8 +43,12 @@ vi.mock(import("./SettingsScopeContext"), async (original) => ({
   ...(await original()),
   useSettingsScope: (() => ({
     scope: { kind: "all", environmentIds: [] },
-    environment: null,
-    connectedEnvironments: [],
+    environment: { environmentId: EnvironmentId.make("representative"), serverConfig: {} },
+    connectedEnvironments: [...state.providers.keys()].map((environmentId) => ({
+      environmentId,
+      serverConfig: {},
+    })),
+    representative: { environmentId: EnvironmentId.make("representative") },
     targets: state.styles.map((style, index) => ({
       environmentId: EnvironmentId.make(`environment-${index}`),
       settings: {
@@ -138,6 +143,7 @@ describe("mixed source control instructions", () => {
 });
 
 it("rejects a scoped model when another environment requires extensions for it", async () => {
+  state.updateSettings.mockReset();
   state.styles = [DEFAULT_UNIFIED_SETTINGS.sourceControlWritingStyle];
   const instanceId = ProviderInstanceId.make("pi");
   state.providerInstances = {
@@ -157,6 +163,7 @@ it("rejects a scoped model when another environment requires extensions for it",
     models: [{ slug: "demo/model", name: "Demo", isCustom: false, capabilities: {} }],
   };
   state.providers = new Map([
+    [EnvironmentId.make("representative"), [provider]],
     [
       EnvironmentId.make("environment-0"),
       [
@@ -184,7 +191,18 @@ it("rejects a scoped model when another environment requires extensions for it",
       </>
     );
   }
-  await using screen = await render(<Availability />);
+  const availability = () => (
+    <>
+      <Availability />
+      <SourceControlWritingSettingsSection />
+    </>
+  );
+  await using screen = await render(availability());
+  await userEvent.click(screen.getByRole("button", { name: "Advanced" }));
+  await userEvent.click(
+    screen.getByRole("switch", { name: "Use a separate source control writer model" }),
+  );
+  expect(state.updateSettings).not.toHaveBeenCalled();
   await expect.element(screen.getByText("Available for threads")).toBeVisible();
   await expect
     .element(
@@ -193,4 +211,15 @@ it("rejects a scoped model when another environment requires extensions for it",
       ),
     )
     .toBeVisible();
+  state.providers = new Map([
+    [EnvironmentId.make("representative"), [provider]],
+    [EnvironmentId.make("environment-0"), [provider]],
+  ]);
+  await screen.rerender(availability());
+  await userEvent.click(
+    screen.getByRole("switch", { name: "Use a separate source control writer model" }),
+  );
+  expect(state.updateSettings).toHaveBeenCalledWith({
+    sourceControlWriterModelSelection: { instanceId, model: "demo/model" },
+  });
 });
diff --git a/apps/web/src/components/settings/SourceControlWritingSettings.tsx b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
index b9885befb18d..205d6aa1d0ca 100644
--- a/apps/web/src/components/settings/SourceControlWritingSettings.tsx
+++ b/apps/web/src/components/settings/SourceControlWritingSettings.tsx
@@ -577,7 +577,21 @@ export function SourceControlWritingSettingsSection() {
                 <Switch
                   checked={usesDedicatedModel}
                   disabled={!usesDedicatedModel && !canEnableDedicatedModel}
-                  onCheckedChange={(checked) =>
+                  onCheckedChange={(checked) => {
+                    if (checked) {
+                      const reason = writerModelDisabledReason(
+                        defaultModelSelection.instanceId,
+                        defaultModelSelection.model,
+                      );
+                      if (reason) {
+                        toastManager.add({
+                          type: "error",
+                          title: "Writer model not saved",
+                          description: reason,
+                        });
+                        return;
+                      }
+                    }
                     updateSettings({
                       sourceControlWriterModelSelection: checked
                         ? createModelSelection(
@@ -586,8 +600,8 @@ export function SourceControlWritingSettingsSection() {
                             defaultModelSelection.options,
                           )
                         : null,
-                    })
-                  }
+                    });
+                  }}
                   aria-label="Use a separate source control writer model"
                 />
               </div>