API Catalog Checker

Check for an RFC 9727 API catalog at /.well-known/api-catalog.

Looks for the standard, machine-readable list of the APIs a publisher offers. An API catalog is how an agent finds a site's APIs without being told where they are. It is only relevant to sites that expose APIs at all.

This is one of the checks the AI Agent Readiness Checker scores under API, Auth, MCP & Skill Discovery, and it can also be run on its own for any URL.

Based on: RFC 9727 — api-catalog: A Well-Known URI and Link Relation to Help Discovery of APIs

About this validation

Checks the /.well-known/api-catalog URI defined by RFC 9727, the standardized machine-readable list of the APIs a publisher offers.

Protocol / standard:: RFC 9727 — api-catalog: A Well-Known URI and Link Relation to Help Discovery of APIs
Rules reviewed:: Nov 11, 2026

Standards and vendor-documented behavior can change. This reflects the source as last reviewed above, not a permanent guarantee.