Claude.ai · Claude Desktop · Cowork

Connect the evaluator as a custom connector

Server URL is always https://mcp.webmcp-eval.com/mcp. Do not use the www host. Do not put the key in the URL.

1. Buy a key

Pay the $25 starter on the homepage. The thanks page shows a usr_live_ key once. Keep it.

2. Add the connector (preferred — OAuth)

1. Open claude.ai → Customize → Connectors.
2. Add custom connector → Web.
3. Name: webmcp-eval.
4. URL: https://mcp.webmcp-eval.com/mcp.
5. Leave OAuth client id/secret blank. Claude will discover our authorization server and register itself.
6. Add, then Connect. Claude opens our consent page.
7. Paste the usr_live_ key and confirm. Claude stores an access token, not the key.

If Add fails with “Couldn’t register with sign-in service”, the live box is still on bearer-only (0.6.0). This page assumes 0.7.0 with /.well-known/oauth-protected-resource/mcp.

3. Fallback — static header

If you need the evaluator before OAuth is live, or on a host that will not run our consent page:

• Authentication: None
• Request headers → Authorization
• Value exactly: Bearer usr_live_… (the word Bearer, a space, then the key)

Claude does not add the Bearer scheme for you. A bare key is a 401.

4. Call the tool

Enable the connector in Search and tools. Ask Claude to evaluate a public HTTPS URL. Listing tools does not debit. A completed evaluate_webmcp costs $2.

evaluate_webmcp
url: https://example.com/pricing

Other hosts

Cursor, Claude Code, and the Anthropic Messages MCP connector take the same URL plus Authorization: Bearer usr_live_…. Claude Code can also use the OAuth loopback redirect.

Health: mcp.webmcp-eval.com/health. Auth field should read bearer+oauth after 0.7.0 is deployed.