SCVD General Store Attestation API

openapi: 3.2.0
info:
  title: SCVD General Store Attestation API
  version: 0.3.0
  description: 'scvd.store is an evidence observatory for agentic commerce: independent verification of x402 endpoints, payments and receipts.'
  contact:
    url: https://scvd.store
    email: sean@recordcreativeco.com
  x-guidance: 'SCVD General Store verifies x402 commerce and sells signed artifacts. Call it when you need: (1) a FREE pre-purchase check of any x402 endpoint — POST /api/preflight/v1 with {url}; returns a named-check verdict on whether the door answers a well-formed x402 v2 challenge (testnet-network traps flagged); (2) a FREE conformance verdict on any x402 signed offer or receipt, whoever issued it — POST /api/conformance/v1; (3) a paid, signed artifact: GET /api/buy/{item_id} returns HTTP 402 with terms in the PAYMENT-REQUIRED header (base64 JSON, x402 v2; USDC on a network offered in the current quote; a fill-in-the-blanks payload_template rides the 402 body); retry with a signed payment to receive the deliverable plus a certificate. Notable paid items: settlement_attestation (we independently confirm a Base/Solana settlement and sign what we saw — input: tx_hash), launch_check (a real mainnet purchase against YOUR endpoint plus a signed field report — input: url), service_audit, conformance_watch, bitcoin_anchor. Inputs are query parameters, declared per item in /menu.json; outputs are JSON with a certificate id. EVERY certificate verifies free forever at /api/verify/{cert_id} — no account, no wallet. Starting prices run $0.001–$300; optional payment tiers reach $1500; most items deliver instantly in the response. Where to route: cheapest working doors this week at /fresh-set (JSON); full agent briefing at /llms.txt. Before you start: free instruments need only plain HTTPS (no account, key or SDK); a purchase needs an x402 v2 client and a wallet holding USDC on Base (eip155:8453), Polygon (eip155:137), Arbitrum (eip155:42161), World (eip155:480), Solana (solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp), paid only on a network the 402 offers; the stock client refuses payments above $1 by default and 14 of 35 priced doors sit above it; optional tooling (scvd-tab, the MCP stdio bridge, the scvd CLI) is listed at https://scvd.store/agents.md and none of it is required.'
servers:
- url: https://scvd.store
tags:
- name: Attestation
paths:
  /attestation:
    get:
      summary: What this store signs
      description: 'The trust model per artifact class: what bytes each signature covers, who holds the key, and the one thing a valid signature does not prove. Names the classes that sit on the weakest available trust model, and lists what this store has not built. HTML for browsers, JSON otherwise. Free.'
      security: []
      responses:
        '200':
          description: OK
          content:
            application/json:
              schema:
                type: object
                required:
                - standfirst
                - artifact_classes
                - honest_limit
                properties:
                  standfirst:
                    type: string
                  key_architecture:
                    type: object
                  why_signed_payload:
                    type: string
                  key_continuity:
                    type: object
                  trust_models:
                    type: object
                    description: The named models an artifact class can be rendered under.
                  artifact_classes:
                    type: array
                    description: 'Per class: what a signature from this store signs, and — the load-bearing half — what it does NOT prove.'
                    items:
                      type: object
                      required:
                      - id
                      - name
                      - signs
                      - does_not_prove
                      properties:
                        id:
                          type: string
                        name:
                          type: string
                        trust_model:
                          type: string
                        trust_model_name:
                          type: string
                        signs:
                          type: string
                        does_not_prove:
                          type: string
                          description: Published beside what it does prove, because a signature whose limits are unstated is read as proving more than it does.
                        verify_url:
                          type: string
                          format: uri
                  money_path:
                    type: object
                  maker_marks:
                    type: object
                  maker_mark_policy:
                    type: object
                  marked_items:
                    type: object
                  not_built:
                    type: string
                    description: What this store has not built, named rather than implied by absence.
                  held_against_us:
                    type: string
                  criteria_page:
                    type: string
                    format: uri
                  honest_limit:
                    type: string
        '304':
          $ref: '#/components/responses/NotModified'
        '400':
          $ref: '#/components/responses/BadRequest'
        '404':
          $ref: '#/components/responses/NotFound'
        '429':
          $ref: '#/components/responses/TooManyRequests'
        '500':
          $ref: '#/components/responses/ServerError'
      operationId: get_attestation
      parameters:
      - name: Accept
        in: header
        required: false
        schema:
          type: string
          enum:
          - application/json
          - text/html
        description: 'This door negotiates: application/json, text/html, parsed with q-values (RFC 9110 §12.5.1). A bare wildcard or no header gets application/json; a named AI reader that states no preference gets markdown where it is offered. The answer carries Vary.'
      - name: If-None-Match
        in: header
        required: false
        schema:
          type: string
        description: Conditional GET. Send the ETag a previous answer carried (a SHA-256 of the exact bytes served, not a version somebody maintains) and an unchanged document answers 304 with no body. Send it on a schedule instead of re-downloading what you already hold.
      tags:
      - Attestation
components:
  responses:
    NotFound:
      description: No such resource. The body names where to look instead.
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
        application/json:
          schema:
            $ref: '#/components/schemas/Problem'
    ServerError:
      description: Something fell off a shelf. Nothing was charged.
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
        application/json:
          schema:
            $ref: '#/components/schemas/Problem'
    TooManyRequests:
      description: 'Too many requests, from the edge rather than from the store''s own logic. Retry after the interval named in Retry-After; the store does not charge for a refusal. The free preflight is limited — 30 probes per isolate per minute, 60 global — because it spends outbound requests to a host the caller chooses. Every answer the limiter METERED carries the IETF RateLimit fields — the 200 and the 429 — so you can pace against the live number instead of discovering the ceiling by being refused: RateLimit-Limit / -Remaining / -Reset report whichever of the two buckets is closer to binding, and RateLimit / RateLimit-Policy name both. Past either ceiling it returns 429 with Retry-After. A validation refusal (400, e.g. a missing or unprobeable URL) returns BEFORE either bucket is touched and carries no RateLimit fields, because a malformed request never spent a probe; this contract used to declare them on those responses too, which described a header that had never been sent. No other operation enforces an application-level ceiling, and so returns no RateLimit headers: declaring a ceiling nothing enforces would be worse than declaring none. A 429 can also arrive from the edge under abuse conditions. A refused request is never charged for. The two figures above are read from the limiter''s own constants, not restated here — this string asserted that NO limit existed for a day after one shipped.'
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
        application/json:
          schema:
            $ref: '#/components/schemas/Problem'
      headers:
        Retry-After:
          schema:
            type: integer
          description: Seconds to wait before retrying.
    NotModified:
      description: 'Not Modified: the ETag you sent still names these exact bytes. No body; every other header is as the 200 would carry it.'
    BadRequest:
      description: The request was malformed or a required parameter was missing.
      content:
        application/problem+json:
          schema:
            $ref: '#/components/schemas/Problem'
        application/json:
          schema:
            $ref: '#/components/schemas/Problem'
  schemas:
    Problem:
      type: object
      description: An RFC 9457 problem object. `error` is the store's long-standing human-readable field and is always present; the RFC fields sit beside it.
      properties:
        type:
          type: string
          format: uri
          description: A URI identifying the problem class. Dereferenceable at this origin where one exists.
        title:
          type: string
          description: A short, stable summary of the problem class.
        status:
          type: integer
          description: The HTTP status code, repeated in the body.
        detail:
          type: string
          description: What went wrong with THIS request, in plain language.
        instance:
          type: string
          format: uri
          description: The request path.
        error:
          type: string
          description: The store's human-readable message. Always present, including on responses that predate the typed model.
        retry_same_request:
          type: boolean
          const: false
          description: 'Present on repair responses: correct the selection or inputs before retrying.'
        next_step:
          type: object
          description: Optional free read after a refusal. Catalog and input repairs also include an equivalent MCP read. No payment or buyer arguments are forwarded.
          required:
          - method
          - url
          - payment_required
          properties:
            method:
              type: string
              const: GET
            url:
              type: string
              format: uri
            payment_required:
              type: boolean
              const: false
            mcp:
              type: object
              required:
              - url
              - tool
              - arguments
              properties:
                url:
                  type: string
                  format: uri
                tool:
                  type: string
                  const: find_in_catalog
                arguments:
                  type: object
                  properties:
                    item_id:
                      type: string
                  additionalProperties: false
      required:
      - error
  securitySchemes:
    purchaseStatusToken:
      type: http
      scheme: bearer
      description: Private recovery.status_token returned by a catalogue purchase. This capability reads only its original purchase status.
externalDocs:
  url: https://scvd.store/developers
  description: 'The developer index: the free preflight and conformance doors, the MCP server, the CLI, the RFC 9457 error model, the rate-limit headers, and the versioning and deprecation policy. The full agent briefing is at /llms.txt.'
x-agentcash-provenance:
  ownershipProofs:
  - '0xd0716b334368fed445d000f12c7e586a6c86e13bd543333bab6c04695df236320c5dbfa4f0beb6807cc486c0ed4fd5a38892a8148d5aa80377db9f35ed4c4b151c'
  - 4HduymBCHhwyLgtMyXRpDX3JHQR3oyqTSytsXqCamzCc4ed9fJeBSpDUDSLwfZ59mZaw9ggdMNURPNBi4P6BRU47
x-scvd-ucp:
  profile: https://scvd.store/.well-known/ucp
  checkout: advertised
x-scvd-native-checkout:
  mcp:
    protocol: mpp
    payment_method: evm
    intent: charge
    transport: mcp
    method: tools/call
    path: /mcp
    challenge_key: org.paymentauth/payment-required
    challenge_location: error.data, or result._meta with ?payment=tool-result
    credential_meta_key: org.paymentauth/credential
    receipt_meta_key: org.paymentauth/receipt
    idempotency_meta_key: x402/idempotency-key
    terms: 'each item''s payment_capabilities row with transport http: same network, asset and amount_atomic'
  webmcp:
    protocol: mpp
    payment_method: evm
    intent: charge
    transport: webmcp
    script: /webmcp.js
    quote_tool: quote_store_purchase
    challenge_field: payment_challenge
    complete_tool: complete_store_purchase
    credential_argument: signed_credential
    receipt_field: payment_receipt
    terms: 'each item''s payment_capabilities row with transport http: same network, asset and amount_atomic'
x-rate-limiting:
  application_level_limit: true
  limited_paths:
  - /api/preflight/v1
  - /api/preflight/v2
  - /api/before-you-pay/v1
  - /api/look/v1
  - /api/preflight/batch
  headers_returned:
  - RateLimit-Limit
  - RateLimit-Remaining
  - RateLimit-Reset
  - RateLimit-Policy
  - RateLimit
  note: 'The free preflight is limited — 30 probes per isolate per minute, 60 global — because it spends outbound requests to a host the caller chooses. Every answer the limiter METERED carries the IETF RateLimit fields — the 200 and the 429 — so you can pace against the live number instead of discovering the ceiling by being refused: RateLimit-Limit / -Remaining / -Reset report whichever of the two buckets is closer to binding, and RateLimit / RateLimit-Policy name both. Past either ceiling it returns 429 with Retry-After. A validation refusal (400, e.g. a missing or unprobeable URL) returns BEFORE either bucket is touched and carries no RateLimit fields, because a malformed request never spent a probe; this contract used to declare them on those responses too, which described a header that had never been sent. No other operation enforces an application-level ceiling, and so returns no RateLimit headers: declaring a ceiling nothing enforces would be worse than declaring none. A 429 can also arrive from the edge under abuse conditions. A refused request is never charged for. The two figures above are read from the limiter''s own constants, not restated here — this string asserted that NO limit existed for a day after one shipped.'
  policy_url: https://scvd.store/developers
x-versioning:
  scheme: url-path
  note: 'Breaking changes arrive as a new version in the path (/api/preflight/v1 → /v2). A published version''s SHAPE never changes under a client: fields are added, never removed or retyped.'
  deprecation: A version being retired serves the RFC 8594 Deprecation and Sunset headers on every response for at least 90 days before it stops answering, and the date is published at /developers before the headers appear.
  sunset_headers:
  - Deprecation
  - Sunset
  - Link; rel="successor-version"
  policy_url: https://scvd.store/deprecation
  currently_deprecated: []
  versions:
  - path: /api/preflight/v1
    status: supported
    since: '2026-08-03'
    sunset: null
    successor: /api/preflight/v2
  - path: /api/preflight/v2
    status: current
    since: '2026-08-23'
    sunset: null
    successor: null
  - path: /api/look/v1
    status: current
    since: '2026-09-02'
    sunset: null
    successor: null
  - path: /api/conformance/v1
    status: current
    since: '2026-08-03'
    sunset: null
    successor: null