fix(server): stop restoring stale OpenCode models

apps/server/src/provider/Layers/ProviderRegistry.test.ts

@@ -545,6 +545,90 @@ it.layer(Layer.mergeAll(NodeServices.layer, ServerSettingsModule.layerTest(), Te
         ]);
       });
 
+      it("drops stale OpenCode models missing from a successful refresh", () => {
+        const previousProvider = {
+          instanceId: ProviderInstanceId.make("opencode"),
+          driver: ProviderDriverKind.make("opencode"),
+          status: "ready",
+          enabled: true,
+          installed: true,
+          auth: { status: "authenticated" },
+          checkedAt: "2026-07-17T00:00:00.000Z",
+          version: "1.0.0",
+          models: [
+            {
+              slug: "github/gpt-5",
+              name: "GPT-5",
+              subProvider: "GitHub",
+              isCustom: false,
+              capabilities: null,
+            },
+            {
+              slug: "removed-plugin/model",
+              name: "Removed Plugin Model",
+              subProvider: "Removed Plugin",
+              isCustom: false,
+              capabilities: null,
+            },
+          ],
+          slashCommands: [],
+          skills: [],
+        } as const satisfies ServerProvider;
+        const refreshedProvider = {
+          ...previousProvider,
+          checkedAt: "2026-07-17T00:01:00.000Z",
+          models: [
+            {
+              slug: "github/gpt-5",
+              name: "GPT-5",
+              subProvider: "GitHub",
+              isCustom: false,
+              capabilities: null,
+            },
+          ],
+        } satisfies ServerProvider;
+
+        assert.deepStrictEqual(mergeProviderSnapshot(previousProvider, refreshedProvider).models, [
+          ...refreshedProvider.models,
+        ]);
+      });
+
+      it("retains stale OpenCode models when a refresh fails", () => {
+        const previousProvider = {
+          instanceId: ProviderInstanceId.make("opencode"),
+          driver: ProviderDriverKind.make("opencode"),
+          status: "ready",
+          enabled: true,
+          installed: true,
+          auth: { status: "authenticated" },
+          checkedAt: "2026-07-17T00:00:00.000Z",
+          version: "1.0.0",
+          models: [
+            {
+              slug: "github/gpt-5",
+              name: "GPT-5",
+              subProvider: "GitHub",
+              isCustom: false,
+              capabilities: null,
+            },
+          ],
+          slashCommands: [],
+          skills: [],
+        } as const satisfies ServerProvider;
+        const refreshedProvider = {
+          ...previousProvider,
+          status: "error",
+          auth: { status: "unknown" },
+          checkedAt: "2026-07-17T00:01:00.000Z",
+          models: [],
+          message: "Failed to refresh OpenCode models.",
+        } satisfies ServerProvider;
+
+        assert.deepStrictEqual(mergeProviderSnapshot(previousProvider, refreshedProvider).models, [
+          ...previousProvider.models,
+        ]);
+      });
+
       it("fills missing capabilities from the previous provider snapshot", () => {
         const previousProvider = {
           instanceId: ProviderInstanceId.make("cursor"),

apps/server/src/provider/Layers/ProviderRegistry.ts

@@ -79,10 +79,16 @@ const hasModelCapabilities = (model: ServerProvider["models"][number]): boolean
   (model.capabilities?.optionDescriptors?.length ?? 0) > 0;
 
 const mergeProviderModels = (
+  provider: ServerProvider,
   previousModels: ReadonlyArray<ServerProvider["models"][number]>,
   nextModels: ReadonlyArray<ServerProvider["models"][number]>,
 ): ReadonlyArray<ServerProvider["models"][number]> => {
-  if (nextModels.length === 0 && previousModels.length > 0) {
+  const shouldRetainMissingModels =
+    provider.driver !== ProviderDriverKind.make("opencode") ||
+    !provider.installed ||
+    provider.status === "error";
+
+  if (shouldRetainMissingModels && nextModels.length === 0 && previousModels.length > 0) {
     return previousModels;
   }
 
@@ -98,7 +104,9 @@ const mergeProviderModels = (
     };
   });
   const nextSlugs = new Set(nextModels.map((model) => model.slug));
-  return [...mergedModels, ...previousModels.filter((model) => !nextSlugs.has(model.slug))];
+  return shouldRetainMissingModels
+    ? [...mergedModels, ...previousModels.filter((model) => !nextSlugs.has(model.slug))]
+    : mergedModels;
 };
 
 export const mergeProviderSnapshot = (
@@ -109,7 +117,7 @@ export const mergeProviderSnapshot = (
     ? nextProvider
     : {
         ...nextProvider,
-        models: mergeProviderModels(previousProvider.models, nextProvider.models),
+        models: mergeProviderModels(nextProvider, previousProvider.models, nextProvider.models),
       };
 
 export const mergeProviderSnapshots = (