fix(auth): document MMX_CONFIG_DIR in credential errors

ERRORS.md

@@ -15,6 +15,7 @@ This document lists all error scenarios and the messages users will see.
 | OAuth error in callback | `OAuth error: ${error}` |
 | OAuth token exchange failed | `OAuth token exchange failed: ${body}` |
 | `MINIMAX_API_KEY` already set (non-interactive) | `Warning: MINIMAX_API_KEY is already set in environment.` |
+| No credentials found (non-interactive) | `No credentials found.` + hint: `Log in: mmx auth login`, `--api-key sk-xxxxx`, or `MMX_CONFIG_DIR=/path/to/.mmx` |
 
 ### `mmx auth logout`
 

README.md

@@ -158,6 +158,17 @@ Useful for CI/CD (`mmx auth login --api-key sk-xxxxx`), or pass per-command via
 OAuth and API key are mutually exclusive — logging in with one clears the other.
 Credential priority: `--api-key` flag > OAuth (config) > `api_key` (config).
 
+### Environment variables
+
+| Variable | Description |
+|---|---|
+| `MINIMAX_REGION` | `global` or `cn`. |
+| `MINIMAX_BASE_URL` | Override the API base URL. |
+| `MINIMAX_OUTPUT` | `text` or `json`. |
+| `MINIMAX_TIMEOUT` | Request timeout in seconds. |
+| `MINIMAX_VERBOSE` | `1` to enable verbose HTTP logging. |
+| `MMX_CONFIG_DIR` | Directory containing the `config.json` file (default: `~/.mmx`). Set this when `mmx` runs from a subprocess, service, or CI job whose home directory differs from where you logged in. |
+
 ### `mmx config` · `mmx quota`
 
 ```bash

src/auth/resolver.ts

@@ -26,6 +26,8 @@ export async function resolveCredential(config: Config): Promise<ResolvedCredent
   throw new CLIError(
     'No credentials found.',
     ExitCode.AUTH,
-    'Log in:        mmx auth login\nPass directly:  --api-key sk-xxxxx',
+    'Log in:          mmx auth login\n' +
+      'Pass per-call:   --api-key sk-xxxxx\n' +
+      'Or set env var:  MMX_CONFIG_DIR=/path/to/.mmx',
   );
 }

src/auth/setup.ts

@@ -46,7 +46,9 @@ export async function ensureAuth(config: Config): Promise<void> {
     throw new CLIError(
       'No credentials found.',
       ExitCode.AUTH,
-      'Log in:        mmx auth login\nPass directly:  --api-key sk-xxxxx',
+      'Log in:          mmx auth login\n' +
+        'Pass per-call:   --api-key sk-xxxxx\n' +
+        'Or set env var:  MMX_CONFIG_DIR=/path/to/.mmx',
     );
   }
 

test/auth/resolver.test.ts

@@ -1,5 +1,7 @@
 import { describe, it, expect, beforeEach, afterEach } from 'bun:test';
 import { resolveCredential } from '../../src/auth/resolver';
+import { ensureAuth } from '../../src/auth/setup';
+import { CLIError } from '../../src/errors/base';
 import type { Config } from '../../src/config/schema';
 import { mkdirSync, rmSync } from 'fs';
 import { join } from 'path';
@@ -59,9 +61,54 @@ describe('resolveCredential', () => {
     await expect(resolveCredential(config)).rejects.toThrow('No credentials found');
   });
 
+  it('no-credentials hint mentions MMX_CONFIG_DIR and working remediation options', async () => {
+    const config = makeConfig();
+    try {
+      await resolveCredential(config);
+      throw new Error('expected resolveCredential to throw');
+    } catch (err) {
+      expect(err).toBeInstanceOf(CLIError);
+      const hint = (err as CLIError).hint ?? '';
+      expect(hint).toContain('mmx auth login');
+      expect(hint).toContain('--api-key');
+      expect(hint).toContain('MMX_CONFIG_DIR');
+    }
+  });
+
   it('prefers flag over file api key', async () => {
     const config = makeConfig({ apiKey: 'sk-flag', fileApiKey: 'sk-file' });
     const cred = await resolveCredential(config);
     expect(cred.token).toBe('sk-flag');
   });
 });
+
+describe('ensureAuth (non-interactive, no credentials)', () => {
+  const testDir = join(tmpdir(), `mmx-setup-test-${Date.now()}`);
+  const originalConfigDir = process.env.MMX_CONFIG_DIR;
+
+  beforeEach(() => {
+    mkdirSync(join(testDir, '.mmx'), { recursive: true });
+    process.env.MMX_CONFIG_DIR = join(testDir, '.mmx');
+  });
+
+  afterEach(() => {
+    if (originalConfigDir) process.env.MMX_CONFIG_DIR = originalConfigDir;
+    else delete process.env.MMX_CONFIG_DIR;
+    delete process.env.MINIMAX_API_KEY;
+    rmSync(testDir, { recursive: true, force: true });
+  });
+
+  it('no-credentials hint mentions MMX_CONFIG_DIR and working remediation options', async () => {
+    const config = makeConfig({ nonInteractive: true });
+    try {
+      await ensureAuth(config);
+      throw new Error('expected ensureAuth to throw');
+    } catch (err) {
+      expect(err).toBeInstanceOf(CLIError);
+      const hint = (err as CLIError).hint ?? '';
+      expect(hint).toContain('mmx auth login');
+      expect(hint).toContain('--api-key');
+      expect(hint).toContain('MMX_CONFIG_DIR');
+    }
+  });
+});