MERCURY JSON Schema Validation API

openapi: 3.2.0
info:
  title: MERCURY x402 storefront JSON Schema Validation API
  version: '1'
  x-spec: mercury-storefront/1
  description: Agent-payable resources over HTTP 402 (x402). LIVE — Base mainnet, real USDC, no token. Only currently-deliverable routes are listed (web-fetch is the live paid SKU; mints are gated off). Free discovery at /.well-known/x402, /x402/discovery, /catalog, and /manifest.
servers:
- url: https://network.mercury-hq.com
tags:
- name: json-schema-validation
paths:
  /buy/validate:
    get:
      summary: Cited Validate — JSON API response vs JSON Schema, signed pass/fail + per-field…
      description: URL (a JSON/API endpoint) + a JSON Schema in → a deterministic pass/fail with per-field errors (missing/wrong-type/enum/range/pattern), plus a signed provenance receipt binding the verdict to the exact response bytes AND the exact schema. Deterministic, keyless, no LLM — x402, USDC on Base mainnet.
      operationId: buy_cited_validate
      tags:
      - json-schema-validation
      responses:
        '200':
          description: Delivered after the x402 payment settles on Base mainnet.
          content:
            application/json:
              schema:
                type: object
                properties:
                  ok:
                    type: boolean
                    description: true when the validation RAN (delivered); false on an honest undeliverable (503-before-charge)
                  url:
                    type: string
                    description: final URL after redirects
                  status:
                    type: integer
                    description: upstream HTTP status of the fetched JSON
                  text:
                    type: string
                    description: 'the canonical signed string: JSON.stringify(report, sorted-keys) — the exact bytes the provenance receipt covers (embeds documentHash + schemaHash + verdict)'
                  fetchedAt:
                    type: string
                    description: ISO timestamp of the fetch (also in the signed attestation)
                  data:
                    type: object
                    description: the validation report the buyer consumes
                    properties:
                      valid:
                        type: boolean
                        description: true iff the fetched JSON conforms to the schema with zero errors
                      errorCount:
                        type: integer
                        description: number of validation errors found
                      errors:
                        type: array
                        description: per-field errors in document order (empty when valid)
                        items:
                          type: object
                          properties:
                            path:
                              type: string
                              description: JSON-Pointer path to the offending value
                            keyword:
                              type: string
                              description: the schema keyword that failed (type, required, enum, minimum, pattern, …)
                            message:
                              type: string
                              description: human-readable reason
                      truncated:
                        type: boolean
                        description: true if the error cap clipped the list (still honest about more existing)
                      documentHash:
                        type: string
                        description: 0x… sha256 of the canonical JSON document that was validated
                      schemaHash:
                        type: string
                        description: 0x… sha256 of the canonical (normalised) schema that was applied
                      schemaForm:
                        type: string
                        description: 'which input form was used: compact | json-schema | shorthand'
                      pointer:
                        type: string
                        description: the JSON-Pointer applied (empty for whole-body validation)
                      validatedType:
                        type: string
                        description: the JSON type of the validated (sub-)document
                  attestation:
                    type: object
                    description: 'EIP-191 provenance receipt over `text` (the canonical sorted-key JSON of the report, which embeds documentHash + schemaHash + verdict), ecrecoverable OFFLINE (key at /.well-known/mercury-attestation). Proves: which schema was checked, which bytes were checked, and the verdict — all at fetchedAt.'
                    properties:
                      keyId:
                        type: string
                      alg:
                        type: string
                      address:
                        type: string
                      contentHash:
                        type: string
                      nonce:
                        type: string
                      signedAt:
                        type: string
                      signature:
                        type: string
                      verify:
                        type: object
                        properties:
                          message:
                            type: string
                          howTo:
                            type: string
                  error:
                    type: string
                    description: present only when ok:false (undeliverable, not charged)
                required:
                - ok
                - url
                additionalProperties: true
        '402':
          description: Payment Required — retry with an x402-signed payment (e.g. x402-fetch). Terms are in the challenge body (x402 v1).
      parameters:
      - name: url
        in: query
        required: true
        schema:
          type: string
          maxLength: 2048
          description: the JSON/API endpoint to fetch + validate (http/https)
        description: the JSON/API endpoint to fetch + validate (http/https)
      - name: schema
        in: query
        required: true
        schema:
          type: string
          maxLength: 16384
          description: 'the JSON Schema to validate against. THREE accepted forms: (1) COMPACT URL-native comma list of field[:type] (type in string|number|integer|boolean|array|object|null; default string), e.g. id:integer,name,price:number,inStock:boolean — every field becomes a REQUIRED typed property; (2) a JSON-Schema string (Draft-07 core subset: type/required/properties/items/enum/const/min*/max*/pattern/format/additionalProperties/nullable/anyOf/oneOf/allOf/not); (3) a shorthand-map string {"id":"integer","name":"string"}.'
        description: 'the JSON Schema to validate against. THREE accepted forms: (1) COMPACT URL-native comma list of field[:type] (type in string|number|integer|boolean|array|object|null; default string), e.g. id:integer,name,price:number,inStock:boolean — every field becomes a REQUIRED typed property; (2) a JSON-Schema string (Draft-07 core subset: type/required/properties/items/enum/const/min*/max*/pattern/format/additionalProperties/nullable/anyOf/oneOf/allOf/not); (3) a shorthand-map string {"id":"integer","name":"string"}.'
      - name: pointer
        in: query
        required: false
        schema:
          type: string
          maxLength: 256
          description: optional JSON-Pointer (e.g. /data or /result/0) to validate a SUB-DOCUMENT of the response instead of the whole body (for APIs that wrap the payload).
        description: optional JSON-Pointer (e.g. /data or /result/0) to validate a SUB-DOCUMENT of the response instead of the whole body (for APIs that wrap the payload).
      x-payment-info:
        protocols:
        - x402
        scheme: exact
        price: $0.005
        currency: USDC
        network: base
        networkCaip2: eip155:8453
        testnet: false
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
        facilitator: https://api.cdp.coinbase.com/platform/v2/x402
        x402Version: 1
      x-x402:
        scheme: exact
        price: $0.005
        currency: USDC
        network: base
        networkCaip2: eip155:8453
        asset: '0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913'
        payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
        facilitator: https://api.cdp.coinbase.com/platform/v2/x402
        testnet: false
        maxTimeoutSeconds: 60
x-payment-info:
  protocols:
  - x402
  network: base
  currency: USDC
  payTo: '0xe10B9d44e72A29B9c19da02981FFCd875308e3C1'
  facilitator: https://api.cdp.coinbase.com/platform/v2/x402
  testnet: false
  spec: mercury-storefront/1