diff --git a/extensions/codex/src/app-server/thread-lifecycle.ts b/extensions/codex/src/app-server/thread-lifecycle.ts
index dbbcb98be95..023eb85544b 100644
--- a/extensions/codex/src/app-server/thread-lifecycle.ts
+++ b/extensions/codex/src/app-server/thread-lifecycle.ts
@@ -393,10 +393,9 @@ function resolveCodexAppServerModelProvider(params: {
     isCodexAppServerNativeAuthProfile(params) &&
     (normalizedLower === "openai" || normalizedLower === "openai-codex")
   ) {
-    // When OpenClaw is forwarding ChatGPT/Codex OAuth, forcing the public
-    // OpenAI model provider makes app-server call api.openai.com without the
-    // ChatGPT bearer and fails with "Missing bearer or basic authentication".
-    // Omit the provider so app-server keeps its native account-backed route.
+    // When OpenClaw is forwarding ChatGPT/Codex OAuth, `openai` is Codex's
+    // native provider id, not a public OpenAI API-key choice. Omit the override
+    // so app-server keeps its configured provider/auth pair for this session.
     return undefined;
   }
   return normalizedLower === "openai-codex" ? "openai" : normalized;
diff --git a/extensions/codex/src/conversation-control.test.ts b/extensions/codex/src/conversation-control.test.ts
index a4a0c883621..0b33fefa35f 100644
--- a/extensions/codex/src/conversation-control.test.ts
+++ b/extensions/codex/src/conversation-control.test.ts
@@ -1,24 +1,37 @@
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
-import { afterEach, beforeEach, describe, expect, it } from "vitest";
+import { clearRuntimeAuthProfileStoreSnapshots } from "openclaw/plugin-sdk/agent-runtime";
+import { upsertAuthProfile } from "openclaw/plugin-sdk/provider-auth";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import {
   readCodexAppServerBinding,
   writeCodexAppServerBinding,
 } from "./app-server/session-binding.js";
 import {
   setCodexConversationFastMode,
+  setCodexConversationModel,
   setCodexConversationPermissions,
 } from "./conversation-control.js";
 
 let tempDir: string;
 
+const sharedClientMocks = vi.hoisted(() => ({
+  getSharedCodexAppServerClient: vi.fn(),
+}));
+
+vi.mock("./app-server/shared-client.js", () => sharedClientMocks);
+
 describe("codex conversation controls", () => {
   beforeEach(async () => {
     tempDir = await fs.mkdtemp(path.join(os.tmpdir(), "openclaw-codex-control-"));
+    vi.stubEnv("OPENCLAW_STATE_DIR", tempDir);
+    sharedClientMocks.getSharedCodexAppServerClient.mockReset();
   });
 
   afterEach(async () => {
+    vi.unstubAllEnvs();
+    clearRuntimeAuthProfileStoreSnapshots();
     await fs.rm(tempDir, { recursive: true, force: true });
   });
 
@@ -47,4 +60,46 @@ describe("codex conversation controls", () => {
       sandbox: "workspace-write",
     });
   });
+
+  it("does not persist public OpenAI provider after model changes on native auth bindings", async () => {
+    const sessionFile = path.join(tempDir, "session.jsonl");
+    upsertAuthProfile({
+      profileId: "work",
+      credential: {
+        type: "oauth",
+        provider: "openai-codex",
+        access: "access-token",
+        refresh: "refresh-token",
+        expires: Date.now() + 60_000,
+      },
+    });
+    await writeCodexAppServerBinding(sessionFile, {
+      threadId: "thread-1",
+      cwd: tempDir,
+      authProfileId: "work",
+      model: "gpt-5.4",
+      modelProvider: "openai",
+    });
+    sharedClientMocks.getSharedCodexAppServerClient.mockResolvedValue({
+      request: vi.fn(async () => ({
+        thread: { id: "thread-1", cwd: tempDir },
+        model: "gpt-5.5",
+        modelProvider: "openai",
+      })),
+    });
+
+    await expect(setCodexConversationModel({ sessionFile, model: "gpt-5.5" })).resolves.toBe(
+      "Codex model set to gpt-5.5.",
+    );
+
+    const raw = await fs.readFile(`${sessionFile}.codex-app-server.json`, "utf8");
+    const binding = await readCodexAppServerBinding(sessionFile);
+    expect(raw).not.toContain('"modelProvider": "openai"');
+    expect(binding).toMatchObject({
+      threadId: "thread-1",
+      authProfileId: "work",
+      model: "gpt-5.5",
+    });
+    expect(binding?.modelProvider).toBeUndefined();
+  });
 });