guides•Last updated: 2026-09-02

Troubleshooting Connection Issues

Diagnose and resolve common More MCP issues: 401 Unauthorized, 403 Forbidden, Cloudflare WAF blocks, and permalink errors.

Diagnostic Checklist

If your AI client cannot connect to More MCP, check these four common failure points first:

Pretty permalinks are enabled in WordPress.
The endpoint URL is accessible over HTTPS.
Your web application firewall (Cloudflare / Wordfence) is not blocking POST requests.
Your authentication header matches the key format.

Symptom: Client reports 404 Not Found when requesting /wp-json/more-mcp/v1/mcp.

Cause: WordPress REST API rewrite rules are not flushed or plain permalinks are in use.

Solution:

In your WordPress admin, go to Settings -> Permalinks.
Ensure you have selected Post name (or any option other than Plain).
Click Save Changes to flush the rewrite rules.
Test the endpoint again in your browser: https://yourdomain.com/wp-json/more-mcp/v1/mcp.

Symptom: {"error": "Unauthorized", "message": "Missing or invalid MMCP-Key header"}.

Cause: The header is missing, corrupted, or stripped by your web server.

Solution:

If you use Apache, some server configurations drop custom headers. Add this directive to your .htaccess file:
```
SetEnvIf Authorization "(.*)" HTTP_AUTHORIZATION=$1
SetEnvIf MMCP-Key "(.*)" HTTP_MMCP_KEY=$1
```
In Nginx, verify that custom headers are permitted:
```
underscores_in_headers on;
```

Symptom: Connection immediately aborted, or returns a Cloudflare challenge page.

Cause: Automated bot protection or WAF rules intercepting POST requests from Node/Python clients.

Solution:

In Cloudflare Dashboard, navigate to Security -> WAF -> Custom Rules.
Create an exclusion rule for your MCP endpoint:
- URI Path starts with: /wp-json/more-mcp/
- Action: Skip (WAF Managed Rules, Bot Fight Mode)
If using Wordfence or iThemes Security, add /wp-json/more-mcp/* to the REST API allowlist.

Symptom: Client connects successfully, but only the ~138 WordPress Core tools appear instead of the expected WooCommerce or Elementor tools.

Solution:

Navigate to More MCP -> Integrations.
Ensure the integration for that plugin is set to Enabled.
More MCP automatically detects active plugins, but individual integrations can be disabled in settings.