openapi: 3.1.0
info:
  title: ACME (RFC 8555) Protocol Account Authorization API
  description: The Automatic Certificate Management Environment (ACME) protocol, defined in IETF RFC 8555, automates the interactions between Certificate Authorities and clients for issuing, renewing, and revoking X.509 certificates. ACME requests are JSON Web Signature (JWS) payloads carried over HTTPS. Server URLs are advertised by each ACME directory; this spec uses generic /acme/* paths.
  version: 1.0.0
  contact:
    name: IETF Datatracker
    url: https://datatracker.ietf.org/doc/html/rfc8555
  license:
    name: IETF Trust
    url: https://trustee.ietf.org/license-info
servers:
- url: https://acme-v02.api.letsencrypt.org
  description: Let's Encrypt production ACME directory (reference implementation)
- url: https://acme-staging-v02.api.letsencrypt.org
  description: Let's Encrypt staging ACME directory
tags:
- name: Authorization
  description: Domain authorization and challenges.
paths:
  /acme/authz/{id}:
    post:
      operationId: getAuthorization
      summary: Retrieve an authorization
      description: Retrieve an authorization, including its challenges (POST-as-GET).
      tags:
      - Authorization
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/jose+json:
            schema:
              $ref: '#/components/schemas/JwsRequest'
      responses:
        '200':
          description: Authorization details
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GenericResponse'
  /acme/chall/{id}:
    post:
      operationId: respondToChallenge
      summary: Respond to a challenge
      description: Submit a challenge response indicating the client is ready for validation.
      tags:
      - Authorization
      parameters:
      - name: id
        in: path
        required: true
        schema:
          type: string
      requestBody:
        required: true
        content:
          application/jose+json:
            schema:
              $ref: '#/components/schemas/JwsRequest'
      responses:
        '200':
          description: Challenge updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/GenericResponse'
components:
  schemas:
    GenericResponse:
      type: object
      additionalProperties: true
    JwsRequest:
      type: object
      description: A JSON Web Signature (JWS) flattened serialization object.
      properties:
        protected:
          type: string
          description: Base64url-encoded JWS Protected Header.
        payload:
          type: string
          description: Base64url-encoded payload.
        signature:
          type: string
          description: Base64url-encoded JWS signature.
      required:
      - protected
      - payload
      - signature
      additionalProperties: true
x-generated-from: https://datatracker.ietf.org/doc/html/rfc8555
x-generated-by: claude-crawl-2026-05-08