diff --git a/packages/adapters/codex-local/src/server/quota.ts b/packages/adapters/codex-local/src/server/quota.ts
index b51f6646..7bc771e4 100644
--- a/packages/adapters/codex-local/src/server/quota.ts
+++ b/packages/adapters/codex-local/src/server/quota.ts
@@ -107,8 +107,8 @@ function parsePlanAndEmailFromToken(idToken: string | null, accessToken: string
   return { email: null, planType: null };
 }
 
-export async function readCodexAuthInfo(): Promise<CodexAuthInfo | null> {
-  const authPath = path.join(codexHomeDir(), "auth.json");
+export async function readCodexAuthInfo(codexHome?: string): Promise<CodexAuthInfo | null> {
+  const authPath = path.join(codexHome ?? codexHomeDir(), "auth.json");
   let raw: string;
   try {
     raw = await fs.readFile(authPath, "utf8");
diff --git a/packages/adapters/codex-local/src/server/test.ts b/packages/adapters/codex-local/src/server/test.ts
index 292e53ee..64af601b 100644
--- a/packages/adapters/codex-local/src/server/test.ts
+++ b/packages/adapters/codex-local/src/server/test.ts
@@ -15,6 +15,7 @@ import {
 } from "@paperclipai/adapter-utils/server-utils";
 import path from "node:path";
 import { parseCodexJsonl } from "./parse.js";
+import { codexHomeDir, readCodexAuthInfo } from "./quota.js";
 
 function summarizeStatus(checks: AdapterEnvironmentCheck[]): AdapterEnvironmentTestResult["status"] {
   if (checks.some((check) => check.level === "error")) return "fail";
@@ -108,12 +109,23 @@ export async function testEnvironment(
       detail: `Detected in ${source}.`,
     });
   } else {
-    checks.push({
-      code: "codex_openai_api_key_missing",
-      level: "warn",
-      message: "OPENAI_API_KEY is not set. Codex runs may fail until authentication is configured.",
-      hint: "Set OPENAI_API_KEY in adapter env, shell environment, or Codex auth configuration.",
-    });
+    const codexHome = isNonEmpty(env.CODEX_HOME) ? env.CODEX_HOME : undefined;
+    const codexAuth = await readCodexAuthInfo(codexHome).catch(() => null);
+    if (codexAuth) {
+      checks.push({
+        code: "codex_native_auth_present",
+        level: "info",
+        message: "Codex is authenticated via its own auth configuration.",
+        detail: codexAuth.email ? `Logged in as ${codexAuth.email}.` : `Credentials found in ${path.join(codexHome ?? codexHomeDir(), "auth.json")}.`,
+      });
+    } else {
+      checks.push({
+        code: "codex_openai_api_key_missing",
+        level: "warn",
+        message: "OPENAI_API_KEY is not set. Codex runs may fail until authentication is configured.",
+        hint: "Set OPENAI_API_KEY in adapter env, shell environment, or run `codex auth` to log in.",
+      });
+    }
   }
 
   const canRunProbe =
diff --git a/server/src/__tests__/codex-local-adapter-environment.test.ts b/server/src/__tests__/codex-local-adapter-environment.test.ts
index a9201c98..ba92a224 100644
--- a/server/src/__tests__/codex-local-adapter-environment.test.ts
+++ b/server/src/__tests__/codex-local-adapter-environment.test.ts
@@ -1,4 +1,4 @@
-import { describe, expect, it } from "vitest";
+import { afterEach, beforeEach, describe, expect, it, vi } from "vitest";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
@@ -7,6 +7,12 @@ import { testEnvironment } from "@paperclipai/adapter-codex-local/server";
 const itWindows = process.platform === "win32" ? it : it.skip;
 
 describe("codex_local environment diagnostics", () => {
+  beforeEach(() => {
+    vi.stubEnv("OPENAI_API_KEY", "");
+  });
+  afterEach(() => {
+    vi.unstubAllEnvs();
+  });
   it("creates a missing working directory when cwd is absolute", async () => {
     const cwd = path.join(
       os.tmpdir(),
@@ -32,6 +38,67 @@ describe("codex_local environment diagnostics", () => {
     await fs.rm(path.dirname(cwd), { recursive: true, force: true });
   });
 
+  it("emits codex_native_auth_present when ~/.codex/auth.json exists and OPENAI_API_KEY is unset", async () => {
+    const root = path.join(
+      os.tmpdir(),
+      `paperclip-codex-auth-${Date.now()}-${Math.random().toString(16).slice(2)}`,
+    );
+    const codexHome = path.join(root, ".codex");
+    const cwd = path.join(root, "workspace");
+
+    try {
+      await fs.mkdir(codexHome, { recursive: true });
+      await fs.writeFile(
+        path.join(codexHome, "auth.json"),
+        JSON.stringify({ accessToken: "fake-token", accountId: "acct-1" }),
+      );
+
+      const result = await testEnvironment({
+        companyId: "company-1",
+        adapterType: "codex_local",
+        config: {
+          command: process.execPath,
+          cwd,
+          env: { CODEX_HOME: codexHome },
+        },
+      });
+
+      expect(result.checks.some((check) => check.code === "codex_native_auth_present")).toBe(true);
+      expect(result.checks.some((check) => check.code === "codex_openai_api_key_missing")).toBe(false);
+    } finally {
+      await fs.rm(root, { recursive: true, force: true });
+    }
+  });
+
+  it("emits codex_openai_api_key_missing when neither env var nor native auth exists", async () => {
+    const root = path.join(
+      os.tmpdir(),
+      `paperclip-codex-noauth-${Date.now()}-${Math.random().toString(16).slice(2)}`,
+    );
+    const codexHome = path.join(root, ".codex");
+    const cwd = path.join(root, "workspace");
+
+    try {
+      await fs.mkdir(codexHome, { recursive: true });
+      // No auth.json written
+
+      const result = await testEnvironment({
+        companyId: "company-1",
+        adapterType: "codex_local",
+        config: {
+          command: process.execPath,
+          cwd,
+          env: { CODEX_HOME: codexHome },
+        },
+      });
+
+      expect(result.checks.some((check) => check.code === "codex_openai_api_key_missing")).toBe(true);
+      expect(result.checks.some((check) => check.code === "codex_native_auth_present")).toBe(false);
+    } finally {
+      await fs.rm(root, { recursive: true, force: true });
+    }
+  });
+
   itWindows("runs the hello probe when Codex is available via a Windows .cmd wrapper", async () => {
     const root = path.join(
       os.tmpdir(),