FN-6414: preserve built-in Z.ai models after extensions

Keep GLM-5.2 visible when user Z.ai extensions replace the provider registration.

- Add shared helpers to clone and register the built-in Z.ai provider safely.
- Re-merge missing built-in Z.ai models after extension provider registration in daemon, serve, dashboard, and pi flows.
- Cover provider replacement behavior in core and dashboard model route tests, and document the extension-preserving behavior.

Files changed:
 .changeset/FN-6414-glm-5-2-visible.md              |  5 ++
 docs/settings-reference.md                         |  2 +-
 packages/cli/src/commands/daemon.ts                | 12 +--
 packages/cli/src/commands/dashboard.ts             | 12 +--
 packages/cli/src/commands/serve.ts                 | 12 +--
 packages/core/src/__tests__/zai-provider.test.ts   | 33 +++++++-
 packages/core/src/index.ts                         |  7 +-
 packages/core/src/zai-provider.ts                  | 93 +++++++++++++++++++++
 ...register-model-routes-zai-real-registry.test.ts | 97 ++++++++++++++++++++++
 packages/engine/src/pi.ts                          | 12 +--
 10 files changed, 250 insertions(+), 35 deletions(-)

Fusion-Task-Id: FN-6414

Fusion-Task-Lineage: f0990da2-968d-4782-8c00-fbc350d6954f

.changeset/FN-6414-glm-5-2-visible.md

@@ -0,0 +1,5 @@
+---
+"@runfusion/fusion": patch
+---
+
+Ensure `zai/glm-5.2` reliably appears in the model list after user Z.ai provider extensions load.

docs/settings-reference.md

@@ -801,7 +801,7 @@ Short-lived token bounds are enforced server-side:
 
 Fusion resolves task models through workflow-backed lane values first, then global lane defaults, then the project/global default model fallback. The common workflow lanes are stored as setting values on the project's default workflow and can be edited with dropdown controls from Settings -> Project Models -> Default workflow model lanes (persisted by the Settings modal's primary Save) or from workflow editor -> Settings -> Values for declared workflow lanes and fallbacks.
 
-Z.ai's built-in provider uses the existing `zai` auth entry / `ZAI_API_KEY` environment variable and includes `zai/glm-5.2` as a selectable model in the same dropdowns and workflow lane controls as the other built-in GLM models.
+Z.ai's built-in provider uses the existing `zai` auth entry / `ZAI_API_KEY` environment variable and includes `zai/glm-5.2` as a selectable model in the same dropdowns and workflow lane controls as the other built-in GLM models. If a pi extension also registers the `zai` provider, Fusion preserves the extension's models and re-adds any missing built-in Z.ai models so built-in GLM choices remain available.
 
 ### Planning model
 

packages/cli/src/commands/daemon.ts

@@ -20,9 +20,9 @@ import {
   GlobalSettingsStore,
   resolveGlobalDir,
   getEnabledPiExtensionPaths,
+  mergeBuiltInZaiProviderModels,
   reconcileClaudeCliPaths,
-  ZAI_PROVIDER_ID,
+  registerBuiltInZaiProvider,
-  ZAI_PROVIDER_REGISTRATION,
 } from "@fusion/core";
 import type { AutomationRunResult, ScheduledTask } from "@fusion/core";
 import { createServer, GitHubClient, createSkillsAdapter, getProjectSettingsPath, loadTlsCredentialsFromEnv, registerGithubTrackingHook } from "@fusion/dashboard";
@@ -554,12 +554,7 @@ export async function runDaemon(opts: DaemonOptions = {}) {
   ]);
   const mergedAuthStorage = mergeAuthStorageReads(authStorage, [supplementalAuthStorage]);
   const modelRegistry = ModelRegistry.create(mergedAuthStorage, getModelRegistryModelsPath());
-  try {
+  registerBuiltInZaiProvider(modelRegistry, (message) => console.log(`[extensions] ${message}`));
-    modelRegistry.registerProvider(ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION);
-  } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
-    console.log(`[extensions] Failed to register built-in ${ZAI_PROVIDER_ID} provider: ${message}`);
-  }
   const dashboardAuthStorage = wrapAuthStorageWithApiKeyProviders(mergedAuthStorage, modelRegistry);
 
   // PackageManager may be used for skills adapter even if extension loading fails
@@ -674,6 +669,7 @@ export async function runDaemon(opts: DaemonOptions = {}) {
     }
 
     extensionsResult.runtime.pendingProviderRegistrations = [];
+    mergeBuiltInZaiProviderModels(modelRegistry, (message) => console.log(`[extensions] ${message}`));
     modelRegistry.refresh();
   } catch (error) {
     const message = error instanceof Error ? error.message : String(error);

packages/cli/src/commands/dashboard.ts

@@ -19,9 +19,9 @@ import {
   isWorkflowColumnsEnabled,
   resolveColumnFlags,
   BUILTIN_CODING_WORKFLOW_IR,
+  mergeBuiltInZaiProviderModels,
   parseWorkflowIr,
-  ZAI_PROVIDER_ID,
+  registerBuiltInZaiProvider,
-  ZAI_PROVIDER_REGISTRATION,
   type WorkflowIrColumn,
   type TraitFlags,
 } from "@fusion/core";
@@ -1371,12 +1371,7 @@ export async function runDashboard(port: number, opts: { paused?: boolean; dev?:
   ]);
   const mergedAuthStorage = mergeAuthStorageReads(authStorage, [supplementalAuthStorage]);
   const modelRegistry = ModelRegistry.create(mergedAuthStorage, getModelRegistryModelsPath());
-  try {
+  registerBuiltInZaiProvider(modelRegistry, (message) => logSink.log(message, "extensions"));
-    modelRegistry.registerProvider(ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION);
-  } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
-    logSink.log(`Failed to register built-in ${ZAI_PROVIDER_ID} provider: ${message}`, "extensions");
-  }
   const dashboardAuthStorage = wrapAuthStorageWithApiKeyProviders(mergedAuthStorage, modelRegistry);
 
   // PackageManager may be used for skills adapter even if extension loading fails.
@@ -1496,6 +1491,7 @@ export async function runDashboard(port: number, opts: { paused?: boolean; dev?:
     }
 
     extensionsResult.runtime.pendingProviderRegistrations = [];
+    mergeBuiltInZaiProviderModels(modelRegistry, (message) => logSink.log(message, "extensions"));
     modelRegistry.refresh();
 
     try {

packages/cli/src/commands/serve.ts

@@ -21,8 +21,8 @@ import {
   GlobalSettingsStore,
   resolveGlobalDir,
   getEnabledPiExtensionPaths,
-  ZAI_PROVIDER_ID,
+  mergeBuiltInZaiProviderModels,
-  ZAI_PROVIDER_REGISTRATION,
+  registerBuiltInZaiProvider,
 } from "@fusion/core";
 import type { AutomationRunResult, ScheduledTask } from "@fusion/core";
 import { createServer, GitHubClient, createSkillsAdapter, getProjectSettingsPath, loadTlsCredentialsFromEnv, registerGithubTrackingHook } from "@fusion/dashboard";
@@ -604,12 +604,7 @@ export async function runServe(
   ]);
   const mergedAuthStorage = mergeAuthStorageReads(authStorage, [supplementalAuthStorage]);
   const modelRegistry = ModelRegistry.create(mergedAuthStorage, getModelRegistryModelsPath());
-  try {
+  registerBuiltInZaiProvider(modelRegistry, (message) => console.log(`[extensions] ${message}`));
-    modelRegistry.registerProvider(ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION);
-  } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
-    console.log(`[extensions] Failed to register built-in ${ZAI_PROVIDER_ID} provider: ${message}`);
-  }
   const dashboardAuthStorage = wrapAuthStorageWithApiKeyProviders(mergedAuthStorage, modelRegistry);
 
   // PackageManager may be used for skills adapter even if extension loading fails
@@ -725,6 +720,7 @@ export async function runServe(
     }
 
     extensionsResult.runtime.pendingProviderRegistrations = [];
+    mergeBuiltInZaiProviderModels(modelRegistry, (message) => console.log(`[extensions] ${message}`));
     modelRegistry.refresh();
 
     try {

packages/core/src/__tests__/zai-provider.test.ts

@@ -1,5 +1,10 @@
 import { describe, expect, it } from "vitest";
-import { ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION } from "../zai-provider.js";
+import {
+  mergeBuiltInZaiProviderModels,
+  registerBuiltInZaiProvider,
+  ZAI_PROVIDER_ID,
+  ZAI_PROVIDER_REGISTRATION,
+} from "../zai-provider.js";
 
 const EXISTING_ZAI_MODELS = [
   "glm-4.5-air",
@@ -45,4 +50,30 @@ describe("ZAI_PROVIDER_REGISTRATION", () => {
       },
     });
   });
+
+  it("re-merges missing built-in models after a user zai extension replacement", () => {
+    const extensionModels = ZAI_PROVIDER_REGISTRATION.models
+      .filter((model) => model.id !== "glm-5.2")
+      .map((model) => ({ ...model }));
+    const registeredProviders = new Map<string, Partial<typeof ZAI_PROVIDER_REGISTRATION>>();
+    const registry = {
+      registeredProviders,
+      registerProvider(providerName: string, config: typeof ZAI_PROVIDER_REGISTRATION) {
+        registeredProviders.set(providerName, { ...registeredProviders.get(providerName), ...config });
+      },
+    };
+
+    registerBuiltInZaiProvider(registry);
+    registry.registerProvider(ZAI_PROVIDER_ID, {
+      ...ZAI_PROVIDER_REGISTRATION,
+      name: "User ZAI extension",
+      models: extensionModels,
+    });
+
+    mergeBuiltInZaiProviderModels(registry);
+
+    const mergedIds = registeredProviders.get(ZAI_PROVIDER_ID)?.models?.map((model) => model.id);
+    expect(mergedIds).toEqual([...EXISTING_ZAI_MODELS, "glm-5.2"]);
+    expect(registeredProviders.get(ZAI_PROVIDER_ID)?.name).toBe("User ZAI extension");
+  });
 });

packages/core/src/index.ts

@@ -20,7 +20,12 @@ export { redactSecrets } from "./redact-secrets.js";
 export * from "./frontend-ux-policy.js";
 export { MOCK_PROVIDER_ID } from "./mock-provider-constants.js";
 export type { MockProviderId, MockSessionPurpose } from "./mock-provider-constants.js";
-export { ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION } from "./zai-provider.js";
+export {
+  ZAI_PROVIDER_ID,
+  ZAI_PROVIDER_REGISTRATION,
+  mergeBuiltInZaiProviderModels,
+  registerBuiltInZaiProvider,
+} from "./zai-provider.js";
 export type { ZaiProviderRegistration } from "./zai-provider.js";
 export {
   resolveWorktrunkSettings,

packages/core/src/zai-provider.ts

@@ -123,3 +123,96 @@ export const ZAI_PROVIDER_REGISTRATION: ZaiProviderRegistration = {
     },
   ],
 };
+
+type ZaiModelLike = Partial<Omit<ZaiModelRegistration, "name" | "api" | "baseUrl" | "compat">> & {
+  id: string;
+  name?: unknown;
+  provider?: string;
+  baseUrl?: unknown;
+  api?: unknown;
+  compat?: unknown;
+};
+
+interface ZaiModelRegistryLike {
+  registerProvider(providerName: string, config: ZaiProviderRegistration): void;
+  getAll?: () => ZaiModelLike[];
+}
+
+type RegistryWithProviderState = ZaiModelRegistryLike & {
+  registeredProviders?: Map<string, Partial<ZaiProviderRegistration>>;
+};
+
+function toZaiModelRegistration(model: ZaiModelLike): ZaiModelRegistration & { baseUrl?: string; api?: string } {
+  return {
+    id: model.id,
+    name: String(model.name ?? model.id),
+    api: typeof model.api === "string" ? model.api : undefined,
+    baseUrl: typeof model.baseUrl === "string" ? model.baseUrl : undefined,
+    reasoning: model.reasoning === true,
+    input: Array.isArray(model.input) ? model.input as ZaiModelInput[] : ["text"],
+    cost: model.cost ?? { input: 0, output: 0, cacheRead: 0, cacheWrite: 0 },
+    contextWindow: Number(model.contextWindow ?? 0),
+    maxTokens: Number(model.maxTokens ?? 0),
+    compat: typeof model.compat === "object" && model.compat !== null
+      ? { ...(model.compat as ZaiModelRegistration["compat"]) }
+      : ZAI_PROVIDER_REGISTRATION.models.find((builtInModel) => builtInModel.id === model.id)?.compat ?? {
+        supportsDeveloperRole: false,
+        thinkingFormat: "zai",
+      },
+  };
+}
+
+function cloneZaiProviderRegistration(config: ZaiProviderRegistration): ZaiProviderRegistration {
+  return {
+    ...config,
+    models: config.models.map((model) => toZaiModelRegistration(model)),
+  };
+}
+
+/**
+ * FNXC:ModelRegistry 2026-06-13-22:04:
+ * pi's registerProvider() treats a provider config with models as a full provider replacement, and user extensions load after Fusion's built-in provider registration.
+ * Re-merge missing built-in Z.ai models after extension registration so zai/glm-5.2 remains visible wherever the user's existing Z.ai extension models are visible, without deleting extension-supplied models.
+ * Always pass cloned configs because pi stores and mutates registered provider objects during later upserts.
+ */
+export function registerBuiltInZaiProvider(
+  modelRegistry: ZaiModelRegistryLike,
+  logWarning: (message: string) => void = () => {},
+): void {
+  try {
+    modelRegistry.registerProvider(ZAI_PROVIDER_ID, cloneZaiProviderRegistration(ZAI_PROVIDER_REGISTRATION));
+  } catch (error) {
+    const message = error instanceof Error ? error.message : String(error);
+    logWarning(`Failed to register built-in ${ZAI_PROVIDER_ID} provider: ${message}`);
+  }
+}
+
+export function mergeBuiltInZaiProviderModels(
+  modelRegistry: ZaiModelRegistryLike,
+  logWarning: (message: string) => void = () => {},
+): void {
+  try {
+    const registryWithState = modelRegistry as RegistryWithProviderState;
+    const registeredProvider = registryWithState.registeredProviders?.get(ZAI_PROVIDER_ID);
+    if (!registeredProvider && !modelRegistry.getAll) return;
+    const registeredModels = registeredProvider?.models?.map((model) => toZaiModelRegistration(model)) ?? [];
+    const currentModels = registeredModels.length > 0
+      ? registeredModels
+      : modelRegistry.getAll?.()
+        .filter((model) => model.provider === ZAI_PROVIDER_ID)
+        .map((model) => toZaiModelRegistration(model)) ?? [];
+    const currentModelIds = new Set(currentModels.map((model) => model.id));
+    const missingBuiltInModels = ZAI_PROVIDER_REGISTRATION.models.filter((model) => !currentModelIds.has(model.id));
+
+    if (missingBuiltInModels.length === 0) return;
+
+    modelRegistry.registerProvider(ZAI_PROVIDER_ID, {
+      ...cloneZaiProviderRegistration(ZAI_PROVIDER_REGISTRATION),
+      ...registeredProvider,
+      models: [...currentModels, ...missingBuiltInModels.map((model) => toZaiModelRegistration(model))],
+    });
+  } catch (error) {
+    const message = error instanceof Error ? error.message : String(error);
+    logWarning(`Failed to merge built-in ${ZAI_PROVIDER_ID} models: ${message}`);
+  }
+}

packages/dashboard/src/__tests__/register-model-routes-zai-real-registry.test.ts

@@ -0,0 +1,97 @@
+import { mkdir, mkdtemp, writeFile } from "node:fs/promises";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { AuthStorage, ModelRegistry } from "@earendil-works/pi-coding-agent";
+import {
+  mergeBuiltInZaiProviderModels,
+  registerBuiltInZaiProvider,
+  ZAI_PROVIDER_REGISTRATION,
+} from "@fusion/core";
+import type { Router } from "express";
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { registerModelRoutes } from "../routes/register-model-routes.js";
+
+const EXISTING_ZAI_MODELS = [
+  "glm-4.5-air",
+  "glm-4.7",
+  "glm-5-turbo",
+  "glm-5.1",
+  "glm-5v-turbo",
+];
+
+async function withTempHome() {
+  const originalHome = process.env.HOME;
+  const home = await mkdtemp(join(tmpdir(), "fusion-zai-models-"));
+  const authDir = join(home, ".fusion", "agent");
+  await mkdir(authDir, { recursive: true });
+  await writeFile(join(authDir, "auth.json"), JSON.stringify({ zai: { type: "api_key", key: "test-zai-key" } }));
+  process.env.HOME = home;
+  return () => {
+    if (originalHome === undefined) {
+      delete process.env.HOME;
+    } else {
+      process.env.HOME = originalHome;
+    }
+  };
+}
+
+function createRouterHarness(modelRegistry: ModelRegistry) {
+  const getHandlers = new Map<string, (req: unknown, res: { json: (body: unknown) => void }) => Promise<void>>();
+  const router = {
+    get: vi.fn((path: string, handler: (req: unknown, res: { json: (body: unknown) => void }) => Promise<void>) => {
+      getHandlers.set(path, handler);
+    }),
+  } as unknown as Router;
+  const store = {
+    getGlobalSettingsStore: () => ({ getSettings: vi.fn().mockResolvedValue({}) }),
+    getSettingsFast: vi.fn().mockResolvedValue({}),
+  };
+  const runtimeLogger = { child: vi.fn(() => ({ warn: vi.fn() })) };
+
+  registerModelRoutes({
+    router,
+    store: store as never,
+    runtimeLogger: runtimeLogger as never,
+    options: { modelRegistry },
+  } as never);
+
+  return getHandlers.get("/models")!;
+}
+
+describe("registerModelRoutes Z.ai real registry", () => {
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
+
+  it("surfaces glm-5.2 through /api/models after a user zai extension replacement", async () => {
+    const restoreHome = await withTempHome();
+    try {
+      const authStorage = AuthStorage.inMemory({ zai: { type: "api_key", key: "test-zai-key" } });
+      const modelRegistry = ModelRegistry.inMemory(authStorage);
+      registerBuiltInZaiProvider(modelRegistry);
+
+      modelRegistry.registerProvider("zai", {
+        ...ZAI_PROVIDER_REGISTRATION,
+        name: "User ZAI extension",
+        models: ZAI_PROVIDER_REGISTRATION.models.filter((model) => model.id !== "glm-5.2"),
+      });
+      expect(modelRegistry.getAvailable().some((model) => model.provider === "zai" && model.id === "glm-5.2")).toBe(false);
+
+      mergeBuiltInZaiProviderModels(modelRegistry);
+      modelRegistry.refresh();
+
+      const allZaiIds = modelRegistry.getAll().filter((model) => model.provider === "zai").map((model) => model.id);
+      expect(allZaiIds).toEqual([...EXISTING_ZAI_MODELS, "glm-5.2"]);
+
+      const handler = createRouterHarness(modelRegistry);
+      const json = vi.fn();
+      await handler({}, { json });
+
+      const response = json.mock.calls[0][0] as { models: Array<{ provider: string; id: string }> };
+      const zaiIds = response.models.filter((model) => model.provider === "zai").map((model) => model.id);
+      expect(zaiIds).toEqual([...EXISTING_ZAI_MODELS, "glm-5.2"]);
+    } finally {
+      restoreHome();
+    }
+  });
+});

packages/engine/src/pi.ts

@@ -42,9 +42,9 @@ import {
   getProjectRootFromWorktree,
   reconcileClaudeCliPaths,
   reconcileDroidCliPaths,
+  mergeBuiltInZaiProviderModels,
+  registerBuiltInZaiProvider,
   resolvePiExtensionProjectRoot,
-  ZAI_PROVIDER_ID,
-  ZAI_PROVIDER_REGISTRATION,
 } from "@fusion/core";
 import type {
   AgentPermissionPolicyActionCategory,
@@ -1364,12 +1364,7 @@ function resolveVendoredDroidCliEntry(): string | null {
 }
 
 async function registerExtensionProviders(cwd: string, modelRegistry: ModelRegistry): Promise<void> {
-  try {
+  registerBuiltInZaiProvider(modelRegistry, (message) => extensionsLog.warn(message));
-    modelRegistry.registerProvider(ZAI_PROVIDER_ID, ZAI_PROVIDER_REGISTRATION);
-  } catch (error) {
-    const message = error instanceof Error ? error.message : String(error);
-    extensionsLog.warn(`Failed to register built-in ${ZAI_PROVIDER_ID} provider: ${message}`);
-  }
 
   try {
     const agentDir = getPackageManagerAgentDir();
@@ -1423,6 +1418,7 @@ async function registerExtensionProviders(cwd: string, modelRegistry: ModelRegis
     }
 
     extensionsResult.runtime.pendingProviderRegistrations = [];
+    mergeBuiltInZaiProviderModels(modelRegistry, (message) => extensionsLog.warn(message));
     modelRegistry.refresh();
   } catch (error) {
     const message = error instanceof Error ? error.message : String(error);