Every API here is available over the APIs.io API and to AI agents over MCP.
openapi: 3.2.0
info:
title: SCVD General Store Replay 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: Replay
paths:
/api/replay/{cert_id}:
get:
summary: Replay a paid call
description: 'One purchase assembled as an integration test an agent can run without trusting this store: the certificate''s signed bytes and their hash, the five accepted x402 terms recovered by matching the catalog against the certificate''s signed quote with a JWS offer over them, the settlement transaction and where to read it, whether the delivery-audit row for that settlement is closed, and the exact refusal body a wrong-scope re-presentation gets. The whole kit is a detached JWS under the store''s did:web key, and it names what the store does not retain. Free.'
security: []
responses:
'200':
description: OK
content:
application/json:
schema:
type: object
description: The replay kit. Every part is derived on the read from the signed record and the live catalog; nothing here is stored beside the certificate.
properties:
artifact_class:
type: string
enum:
- replay_kit
call:
type: object
description: 'Which paid call this is: cert_id, item, patron_number, date.'
offer:
type: object
description: quote (the signed hash), accepted_terms (the five recovered, or null), recovered_from (how, or why not), jws (an offer signed over those terms on this read, or null), kid and did_document to resolve the key.
settlement:
type: object
description: state, transaction, network, explorer, payer, paid_usdc, and the sale's standing including the delivery-audit row.
response:
type: object
description: form, signed_payload, signature, signature_jcs, public_key, artifact_hash — everything an ed25519 check needs.
refusal:
type: object
description: 'wrong_scope: the purchase_input_mismatch body a settled payment gets when re-presented against a different product or inputs, charged once and never twice, plus the other refusal codes by name.'
replay:
type: array
items:
type: string
description: The steps, in order, to check all of it yourself.
not_retained:
type: array
items:
type: string
description: What this store does not keep, said out loud rather than left to be discovered.
kit_signature:
type: object
description: Detached JWS over the kit's RFC 8785 form. Proves this store assembled these parts on this read; makes no part truer than its own signature does.
'400':
$ref: '#/components/responses/BadRequest'
'404':
$ref: '#/components/responses/NotFound'
'429':
$ref: '#/components/responses/TooManyRequests'
'500':
$ref: '#/components/responses/ServerError'
parameters:
- name: cert_id
in: path
required: true
schema:
type: string
description: Any cert_id this store has issued; every purchase response and verify answer carries one.
operationId: get_api_replay_cert_id
tags:
- Replay
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.
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