Agent Readiness

/.well-known/api-catalog (RFC 9727)

RFC 9727 defines `/.well-known/api-catalog` as the canonical machine entrypoint for discovering an organization's APIs, formatted as an RFC 9264 linkset. Presence of a catalog at this path is one of the cheapest, highest-impact agent-readiness signals — agents do not have to crawl HTML to find specs. As of 2026-05-22, a survey of 74 likely-candidate providers found only four serving a real RFC 9727 linkset at the well-known path — Cloudflare, Memesio, Merge.dev, and Zuplo — with example signal records committed for each.

Documentation GitHub

Documentation

📖

Documentation

https://www.rfc-editor.org/rfc/rfc9727.html

📖

Documentation

https://www.rfc-editor.org/rfc/rfc9264.html

Other Resources

🔗

Examples

https://raw.githubusercontent.com/api-evangelist/agent-readiness/refs/heads/main/examples/agent-readiness-signal-cloudflare-well-known-catalog-example.json

🔗

Examples

https://raw.githubusercontent.com/api-evangelist/agent-readiness/refs/heads/main/examples/agent-readiness-signal-memesio-well-known-catalog-example.json

🔗

Examples

https://raw.githubusercontent.com/api-evangelist/agent-readiness/refs/heads/main/examples/agent-readiness-signal-merge-well-known-catalog-example.json

🔗

Examples

https://raw.githubusercontent.com/api-evangelist/agent-readiness/refs/heads/main/examples/agent-readiness-signal-zuplo-well-known-catalog-example.json

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find_apisBrowse and filter every API in the catalog.
get_api_artifactsOne API's artifacts, grouped by type.
get_openapiThe primary OpenAPI for this API.
find_similar_apisAPIs that look like this one.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

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curl "https://apis.io/api/v1/apis/well-known-api-catalog"

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API entry from apis.yml

aid: agent-readiness:well-known-api-catalog
name: /.well-known/api-catalog (RFC 9727)
tags:
- Discovery
- Linkset
- Agent Readiness
- Standards
humanURL: https://www.rfc-editor.org/rfc/rfc9727.html
baseURL: https://www.rfc-editor.org/rfc/rfc9727.html
properties:
- url: https://www.rfc-editor.org/rfc/rfc9727.html
  type: Documentation
- url: https://www.rfc-editor.org/rfc/rfc9264.html
  type: Documentation
- url: examples/agent-readiness-signal-cloudflare-well-known-catalog-example.json
  type: Examples
- url: examples/agent-readiness-signal-memesio-well-known-catalog-example.json
  type: Examples
- url: examples/agent-readiness-signal-merge-well-known-catalog-example.json
  type: Examples
- url: examples/agent-readiness-signal-zuplo-well-known-catalog-example.json
  type: Examples
description: RFC 9727 defines `/.well-known/api-catalog` as the canonical machine entrypoint for discovering
  an organization's APIs, formatted as an RFC 9264 linkset. Presence of a catalog at this path is one
  of the cheapest, highest-impact agent-readiness signals — agents do not have to crawl HTML to find specs.
  As of 2026-05-22, a survey of 74 likely-candidate providers found only four serving a real RFC 9727
  linkset at the well-known path — Cloudflare, Memesio, Merge.dev, and Zuplo — with example signal records
  committed for each.