openapi: 3.2.0 info: title: SCVD General Store MCP 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: MCP paths: /mcp: post: summary: The MCP door description: 'The store as a Model Context Protocol server (streamable HTTP, JSON-RPC 2.0). initialize and tools/list are free; buy_* tools return error 402 with x402 terms in error.data and settle in-band. This is the canonical endpoint; the manifest is at /.well-known/mcp (also /.well-known/mcp.json), and both of those paths POST to this same handler for clients that speak the protocol at the document rather than reading the address out of it. A GET with Accept: text/event-stream opens the listening channel (a keepalive-only stream; the server sends nothing unprompted); any other GET answers 405 with Allow: POST and the whole handshake in the body.' security: [] responses: '200': description: OK content: application/json: schema: type: object required: - jsonrpc properties: jsonrpc: type: string enum: - '2.0' id: description: Echoed from the request. Absent on a notification. result: type: object description: Shaped by the method called — tools/list returns tools, resources/read returns contents, and so on. The shapes are the Model Context Protocol's rather than this store's; the free server card at /.well-known/mcp names the methods and capabilities actually served. error: type: object description: JSON-RPC error. The buy_* tools carry their x402 payment terms in error.data on the first call — a 402 expressed in the protocol's own vocabulary rather than an HTTP status this transport cannot use. properties: code: type: integer message: type: string data: type: object '400': $ref: '#/components/responses/BadRequest' '404': $ref: '#/components/responses/NotFound' '429': $ref: '#/components/responses/TooManyRequests' '500': $ref: '#/components/responses/ServerError' requestBody: required: true description: One JSON-RPC 2.0 request. `initialize` is the handshake. content: application/json: schema: type: object required: - jsonrpc - method properties: jsonrpc: type: string const: '2.0' id: oneOf: - type: string - type: integer description: Omit for a notification; the store answers nothing. method: type: string description: initialize, ping, tools/list, tools/call, resources/list, resources/read, prompts/list. params: type: object additionalProperties: true description: Per the MCP spec for the named method. A paid tools/call carries its x402 payment in the request _meta. parameters: - name: item_id in: query description: Expose just this item's buy tool, with required inputs at the schema root. schema: type: string enum: - spot_check - settlement_attestation - small_blessing - settlement_reconciliation - daily_fortune - the_confession - attestation_bundle - the_mandate - the_case_file - window_pick - hello - good_buyer - signature_agent_card - the_statement - luckies - pack - coffees_for_closers - bitcoin_anchor - context_anchor - passport_refresh - graffiti_on_a_train - a2a_repair_kit - standing_watch - service_audit - conformance_watch - onpage_audit - launch_check - opening_day - provenance_check - recurring_patronage - trust_profile - operator_statement - certificate_of_patronage - aura_walk - the_collab - name: view in: query description: compact omits store extensions; with item_id it also shortens the description. schema: type: string enum: - full - compact - name: payment in: query description: tool-result uses x402 MCP isError:true + structuredContent for challenges; omission preserves error 402. Supply payment in params._meta['x402/payment']; success receipt is result._meta['x402/payment-response']. schema: type: string enum: - tool-result operationId: post_mcp tags: - MCP 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