Preserve built-in agent adapter config on reconcile

Co-Authored-By: Paperclip <noreply@paperclip.ing>

server/src/__tests__/built-in-agents.test.ts

@@ -163,6 +163,13 @@ describeEmbeddedPostgres("built-in agents", () => {
       adapterConfig: { model: "gpt-5.4" },
     });
 
+    const reconciled = await svc.ensure(companyId, "briefs");
+    expect(reconciled.status).toBe("ready");
+    expect(reconciled.agent).toMatchObject({
+      adapterType: "codex_local",
+      adapterConfig: { model: "gpt-5.4" },
+    });
+
     const rows = await db.select().from(agents).where(eq(agents.companyId, companyId));
     expect(rows).toHaveLength(1);
   });

server/src/services/built-in-agents.ts

@@ -1307,8 +1307,16 @@ export function builtInAgentService(db: Db) {
   async function ensure(companyId: string, key: string, input: BuiltInAgentProvisionInput = {}) {
     const definition = requireBuiltInAgentDefinition(key);
     await ensureCompany(companyId);
-    const resolvedInput = await defaultProvisionInput(companyId, definition, input);
     const existing = await findSingleAgent(companyId, definition);
+    const preserveExistingAdapter = Boolean(
+      existing
+      && input.adapterType === undefined
+      && input.adapterConfig === undefined
+      && hasCompleteAdapterConfig(existing.adapterType, existing.adapterConfig),
+    );
+    const resolvedInput = preserveExistingAdapter
+      ? input
+      : await defaultProvisionInput(companyId, definition, input);
     if (existing) {
       const patch: Partial<typeof agents.$inferInsert> = {
         metadata: builtInMetadata(definition, existing.metadata),