fix(codex): keep native sessions out of custom provider imports

docs/custom-providers.md

@@ -232,7 +232,7 @@ For pay-as-you-go, use `ANTHROPIC_API_KEY` with a standard Model Studio key (`sk
 
 Codex talks to OpenAI's Responses API by default. Custom providers that extend `"codex"` can point Codex at any OpenAI-compatible endpoint (OpenRouter, LiteLLM, vLLM, llama.cpp server, an internal gateway, etc.) by setting `OPENAI_BASE_URL` and `OPENAI_API_KEY` in the provider `env`.
 
-Paseo passes those variables through to the Codex app-server process **and** maps them into Codex's thread config under `model_provider` / `model_providers`, because Codex reads provider routing from config rather than from `OPENAI_BASE_URL` alone. The generated Codex provider key is `paseo:<provider-id>`, so a Paseo provider such as `ollama` does not override a Codex built-in. Existing sessions created with the original provider key remain available in Import session.
+Paseo passes those variables through to the Codex app-server process **and** maps them into Codex's thread config under `model_provider` / `model_providers`, because Codex reads provider routing from config rather than from `OPENAI_BASE_URL` alone. The generated Codex provider key is `paseo:<provider-id>`, so a Paseo provider such as `ollama` does not override a Codex built-in. Existing custom sessions created with a non-built-in provider key remain available in Import session. Native Codex conversations using a built-in key stay separate from a custom provider of the same name.
 
 ### Setup
 

packages/server/src/server/agent/providers/codex-app-server-agent.test.ts

@@ -6942,6 +6942,33 @@ describe("Codex importable sessions", () => {
     appServer.assertNoErrors();
   });
 
+  test.each(["openai", "ollama", "lmstudio", "amazon-bedrock", "amazon-bedrock-runtime"])(
+    "a custom provider named %s excludes native built-in sessions",
+    async (providerId) => {
+      const appServer = createFakeCodexAppServer({
+        "thread/list": providerFilteringThreadListHandler([
+          { id: "native-thread", cwd: "/workspace/project-a", modelProvider: providerId },
+          {
+            id: "custom-thread",
+            cwd: "/workspace/project-a",
+            modelProvider: `paseo:${providerId}`,
+          },
+        ]),
+      });
+      const provider = createProviderWithFakeAppServer(appServer, {
+        runtimeSettings: {
+          env: { OPENAI_BASE_URL: "https://llm.example.test/v1", OPENAI_API_KEY: "test-key" },
+        },
+        customProvider: { id: providerId, label: "Custom Codex", extends: "codex" },
+      });
+
+      const sessions = await provider.listImportableSessions({ cwd: "/workspace/project-a" });
+
+      expect(sessions.map((session) => session.providerHandleId)).toEqual(["custom-thread"]);
+      appServer.assertNoErrors();
+    },
+  );
+
   test("stock Codex keeps listing only its own threads", async () => {
     const appServer = createFakeCodexAppServer({
       "thread/list": providerFilteringThreadListHandler(threadsByModelProvider),

packages/server/src/server/agent/providers/codex-app-server-agent.ts

@@ -145,6 +145,15 @@ function isCodexAlreadyUnarchivedError(error: unknown, threadId: string): boolea
 const TURN_START_TIMEOUT_MS = 90 * 1000;
 const INTERRUPT_TIMEOUT_MS = 2_000;
 const CODEX_PROVIDER = "codex" as const;
+// These native provider identities belong to Codex, not to an older custom
+// Paseo provider. Never include them in a custom provider's legacy import scan.
+const CODEX_BUILTIN_MODEL_PROVIDER_IDS = new Set([
+  "openai",
+  "ollama",
+  "lmstudio",
+  "amazon-bedrock",
+  "amazon-bedrock-runtime",
+]);
 // Codex treats most app-server client names as the model-request originator.
 // This reserved Codex name is non-originating, so requests keep Codex's default
 // CLI identity instead of showing up as Paseo in provider usage logs.
@@ -7353,13 +7362,17 @@ export class CodexAppServerAgentClient implements AgentClient {
       const listLimit = options?.cwd ? Math.max(scanLimit, 50) : scanLimit;
       // Codex records each thread under the model provider that ran it and,
       // unless told otherwise, lists only the provider its own config selects.
-      // Include the original id for sessions created before namespacing.
+      // Include legacy custom ids, but keep Codex built-in sessions separate.
       const customProviderConfig = this.customProviderConfig();
       const allThreads = await readCodexThreadWindow(client, this.logger, {
         limit: listLimit,
         cwd: options?.cwd,
         ...(customProviderConfig && this.deps.customProvider
-          ? { modelProviders: [customProviderConfig.model_provider, this.deps.customProvider.id] }
+          ? {
+              modelProviders: CODEX_BUILTIN_MODEL_PROVIDER_IDS.has(this.deps.customProvider.id)
+                ? [customProviderConfig.model_provider]
+                : [customProviderConfig.model_provider, this.deps.customProvider.id],
+            }
           : {}),
       });
       const threads = filterCodexThreadsByCwd(allThreads, options?.cwd);

packages/server/src/server/agent/providers/codex-custom-provider-import.local.e2e.test.ts

@@ -90,12 +90,13 @@ describe("Codex custom provider import list", () => {
   });
 
   test.each([
-    { providerId: "my-codex", seedLegacy: false },
-    { providerId: "ollama", seedLegacy: false },
-    { providerId: "my-codex", seedLegacy: true },
+    { providerId: "my-codex", seedLegacy: false, seedBuiltin: false },
+    { providerId: "ollama", seedLegacy: false, seedBuiltin: false },
+    { providerId: "my-codex", seedLegacy: true, seedBuiltin: false },
+    { providerId: "ollama", seedLegacy: false, seedBuiltin: true },
   ])(
-    "lists and imports sessions for $providerId (legacy session: $seedLegacy)",
-    async ({ providerId, seedLegacy }) => {
+    "lists and imports sessions for $providerId (legacy: $seedLegacy, native: $seedBuiltin)",
+    async ({ providerId, seedLegacy, seedBuiltin }) => {
       const codexHome = mkdtempSync(path.join(os.tmpdir(), "codex-custom-import-home-"));
       const cwd = mkdtempSync(path.join(os.tmpdir(), "codex-custom-import-cwd-"));
       cleanups.push(() => rmSync(codexHome, { recursive: true, force: true }));
@@ -104,11 +105,12 @@ describe("Codex custom provider import list", () => {
       cleanups.push(() => closeServer(server));
 
       const logger = createTestLogger();
-      if (seedLegacy) {
-        // Recreate the config emitted before namespacing with the real app-server.
+      if (seedLegacy || seedBuiltin) {
+        // Seed an old custom session or a native built-in session with real Codex.
         const environment = {
           ...process.env,
           CODEX_HOME: codexHome,
+          CODEX_OSS_BASE_URL: baseUrl,
           OPENAI_API_KEY: "test-key",
         };
         const legacy = new CodexAppServerAgentSession(
@@ -120,15 +122,17 @@ describe("Codex custom provider import list", () => {
             environment,
             customCodexConfig: {
               model_provider: providerId,
-              model_providers: {
-                [providerId]: {
-                  name: "My Codex",
-                  base_url: baseUrl,
-                  wire_api: "responses",
-                  env_key: "OPENAI_API_KEY",
-                  requires_openai_auth: false,
-                },
-              },
+              model_providers: seedBuiltin
+                ? {}
+                : {
+                    [providerId]: {
+                      name: "My Codex",
+                      base_url: baseUrl,
+                      wire_api: "responses",
+                      env_key: "OPENAI_API_KEY",
+                      requires_openai_auth: false,
+                    },
+                  },
             },
           },
         );