OpenAPI for agents

An OpenAPI document is a machine-readable contract. Agents that find your spec can reason about your API without scraping HTML docs or guessing parameter names — which is the difference between a reliable integration and a hallucinated one.

Where to publish it

• /openapi.json (most common)
• /openapi.yaml
• /.well-known/openapi.json
• Linked from your llms.txt under a Docs section.

Minimum viable spec

{
  "openapi": "3.1.0",
  "info": { "title": "Acme API", "version": "1.0.0" },
  "servers": [{ "url": "https://api.acme.com" }],
  "paths": {
    "/widgets": {
      "get": {
        "summary": "List widgets",
        "responses": { "200": { "description": "OK" } }
      }
    }
  }
}