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OpenAPI Specification

openapi: 3.2.0
info:
  title: Quartermaster X402 Audit API
  version: 1.6.0
  description: Small, reliable utility APIs for AI agents. Paid endpoints charge per call in USDC over the x402 protocol (HTTP 402 flow) - no accounts, no API keys. Free endpoints are open.
  contact:
    url: https://quartermaster.surewhynot.app
servers:
- url: https://quartermaster.surewhynot.app
tags:
- name: X402 Audit
paths:
  /v1/x402-audit:
    get:
      summary: Full scored audit of an x402 endpoint (workflow)
      description: 'Runs the complete audit sequence in one call: 402 challenge verification, payment-field judgment (version, network, asset, payTo), Bazaar discovery metadata check, and origin discovery probes (llms.txt, openapi.json, .well-known/x402, discovery/resources). Returns a 0-100 score, pass/warn/fail checks with evidence, and recommended fixes.'
      parameters:
      - name: url
        in: query
        required: true
        description: x402 paid endpoint to audit
        schema:
          type: string
          format: uri
      responses:
        '200':
          description: Scored audit report
          content:
            application/json:
              schema:
                type: object
        '400':
          description: Invalid input
          content:
            application/json:
              schema:
                type: object
        '402':
          description: Payment required
          content:
            application/json:
              schema:
                type: object
      x-payment:
        protocol: x402
        price: $0.01
        currency: USDC
        note: Unpaid requests receive 402 Payment Required with machine-readable payment requirements.
      tags:
      - X402 Audit
      operationId: getV1X402Audit
      x-operation-id-source: derived
externalDocs:
  description: 'Buyer quickstart: how to pay with x402'
  url: https://quartermaster.surewhynot.app/buyers