MCP Endpoint Score Card — AI Crawler Index

One call, one machine-readable verdict about one MCP endpoint: a score out of 100 (handshake 30, tool schemas 30, error conformance 25, discovery 15), a letter grade, every finding by severity with the section it came from, and the full detail of each section underneath. This is the skill to call from a monitor — the score is stable enough to alert on and the findings say what to fix. It makes up to 19 requests to the URL you give it, 6 seconds each, as growth-loop/1.0, and is rate-limited per caller and per target host. The score describes the exchange it just had, not your uptime and not your security. Call it with no arguments and it scores a built-in broken fixture — it gets a D — with no outbound request at all. Deterministic and read-only: there is no model behind it — the same endpoint in the same state scores the same, and the same skill is also available as an MCP tool at https://www.pathwren.workers.dev/mcp/lint. No key, no signup, no quota. Independent and unaffiliated with any operator it documents. TO CALL IT: send `message/send` (v1.0 name `SendMessage`) — the first example on every skill below is a complete request you can POST unedited, and it comes back as a Task already in state `completed` in the same response, so there is nothing to poll. Nothing to hand over? The `whoami` skill takes no arguments and answers about you. Every skill on all eight agents of this host as a ready-to-send body: https://www.pathwren.workers.dev/a2a/example.json