Security · x402 · early usage

Audit a real request against the OpenAPI document it should satisfy

by api.zfinia.com · discovered, not yet claimed by its owner · updated 2026-10-04

30d calls1

30d payers1

MethodPOST

Outputjson

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

Audit a real request against the OpenAPI document it should satisfy. Matches the operation the way a router would, checks every path, query and header parameter against its declared schema, validates the body against the declared media type, and reports whether the credential the declared security scheme expects is present. You supply the request, so this works against an API nothing external can reach.

Tags: openapi · request validation · api contract · integration testing · developer tooling · bazaar

Call contract

Method: POST
Input: json
Output: json
Last paid call: 2026-10-04

Input example from Bazaar metadata

{
  "request": {
    "headers": {
      "X-Api-Key": "redacted"
    },
    "method": "GET",
    "path": "/orders",
    "query": {
      "page": "first"
    }
  },
  "specification": {
    "components": {
      "schemas": {
        "Order": {
          "properties": {
            "id": {
              "type": "string"
            },
            "status": {
              "enum": [
                "open",
                "shipped",
                "disputed"
              ],
              "type": "string"
            },
            "tenant_id": {
              "type": "string"
            },
            "total": {
              "type": "number"
            }
          },
          "required": [
            "id",
            "total",
            "tenant_id"
          ],
          "type": "object"
        }
      },
      "securitySchemes": {
        "apiKey": {
          "in": "query",
          "name": "api_key",
          "type": "apiKey"
        }
      }
    },
    "info": {
      "title": "Orders API",
      "version": "2.0.0"
    },
    "openapi": "3.1.0",
    "paths": {
      "/orders": {
        "get": {
          "operationId": "listOrdersV2",
          "parameters": [
            {
              "in": "query",
              "name": "tenant",
              "required": true,
              "schema": {
                "type": "string"
              }
            }
          ],
          "responses": {
            "200": {
              "content": {
                "application/json": {
                  "schema": {
                    "items": {
                      "$ref": "#/components/schemas/Order"
                    },
                    "type": "array"
                  }
                }
              },
              "description": "A page of orders"
            }
          },
          "summary": "List orders"
        },
        "parameters": [
          {
            "in": "query",
            "name": "page",
            "schema": {
              "minimum": 1,
              "type": "integer"
            }
          }
        ],
        "post": {
          "operationId": "createOrder",
          "requestBody": {
            "content": {
              "application/json": {
                "schema": {
                  "$ref": "#/components/schemas/Order"
                }
              }
            },
            "required": true
          },
          "responses": {
            "201": {
              "content": {
                "application/json": {
                  "schema": {
                    "$ref": "#/components/schemas/Order"
                  }
                }
              },
              "description": "Created"
            }
          },
          "summary": "Create an order"
        }
      },
      "/orders/{id}": {
        "get": {
          "deprecated": true,
          "operationId": "getOrder",
          "parameters": [
            {
              "in": "path",
              "name": "id",
              "schema": {
                "type": "string"
              }
            }
          ],
          "responses": {
            "200": {
              "content": {
                "application/json": {
                  "schema": {
                    "$ref": "#/components/schemas/Order"
                  }
                }
              },
              "description": "The order"
            },
            "404": {
              "description": "Not found"
            }
          },
          "summary": "Fetch one order"
        }
      }
    },
    "security": [
      {
        "apiKey": []
      }
    ]
  }
}

Output example

{
  "assumptions": [
    "A literal path segment is preferred over a template, as a router would, so /pets/mine is audited against its own operation rather than /pets/{id}.",
    "Path, query and header values arrive as text, so a value declared as an integer is checked against its text form rather than rejected for being a string.",
    "Header names are compared case-insensitively."
  ],
  "checked": {
    "body": false,
    "header_parameters": 0,
    "path_parameters": 0,
    "query_parameters": 2
  },
  "complete": true,
  "conformant": false,
  "finding_count": 3,
  "findings": [
    {
      "code": "TYPE_MISMATCH",
      "detail": "GET /orders: query parameter page Expected integer, found string.",
      "location": "query",
      "operation": "GET /orders",
      "parameter": "page"
    },
    {
      "code": "REQUIRED_PARAMETER_MISSING",
      "detail": "GET /orders: required query parameter tenant is absent from the request.",
      "location": "query",
      "operation": "GET /orders",
      "parameter": "tenant"
    },
    {
      "code": "SECURITY_REQUIREMENT_UNMET",
      "detail": "GET /orders requires apiKey and the request carries no matching credential.",
      "operation": "GET /orders"
    }
  ],
  "findings_by_code": {
    "REQUIRED_PARAMETER_MISSING": 1,
    "SECURITY_REQUIREMENT_UNMET": 1,
    "TYPE_MISMATCH": 1
  },
  "limitations": [
    "Conformance of one request against the supplied specification. Whether the specification is correct is not assessed.",
    "conformant is true only when every declared constraint for the matched operation was evaluated and none failed."
  ],
  "limits": {
    "maxClientOperations": 200,
    "maxFindings": 500,
    "maxOperations": 500,
    "maxRequestBodyBytes": 262144
  },
  "matched_operation": "GET /orders",
  "matched_path_template": "/orders",
  "not_examined": [],
  "observed_at": "2026-10-02T00:00:00.000Z",
  "operation_deprecated": false,
  "operation_id": "listOrdersV2",
  "path_variables": {},
  "request_id": "example-request",
  "service_id": "openapi_parameter_contract_audit",
  "service_version": "1.0.0"
}

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/34029.json for the price and payment options.
Pay. Call GET https://api.zfinia.com/x402/v1/openapi-parameter-contract-audit. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.14 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base
Demand: 1 calls · 1 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.14	0x25e8245f07d5e4873987293dad666afbe56a9608	60s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x25e8245f07d5e4873987293dad666afbe56a9608",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "140000",
    "amountUsd": 0.14,
    "maxTimeoutSeconds": 60
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "example": {},
  "type": "string"
}

Examples

curl

curl -X POST 'https://api.zfinia.com/x402/v1/openapi-parameter-contract-audit' -H 'Content-Type: application/json' --data '{"request":{"headers":{"X-Api-Key":"redacted"},"method":"GET","path":"/orders","query":{"page":"first"}},"specification":{"components":{"schemas":{"Order":{"properties":{"id":{"type":"string"},"status":{"enum":["open","shipped","disputed"],"type":"string"},"tenant_id":{"type":"string"},"total":{"type":"number"}},"required":["id","total","tenant_id"],"type":"object"}},"securitySchemes":{"apiKey":{"in":"query","name":"api_key","type":"apiKey"}}},"info":{"title":"Orders API","version":"2.0.0"},"openapi":"3.1.0","paths":{"/orders":{"get":{"operationId":"listOrdersV2","parameters":[{"in":"query","name":"tenant","required":true,"schema":{"type":"string"}}],"responses":{"200":{"content":{"application/json":{"schema":{"items":{"$ref":"#/components/schemas/Order"},"type":"array"}}},"description":"A page of orders"}},"summary":"List orders"},"parameters":[{"in":"query","name":"page","schema":{"minimum":1,"type":"integer"}}],"post":{"operationId":"createOrder","requestBody":{"content":{"application/json":{"schema":{"$ref":"#/components/schemas/Order"}}},"required":true},"responses":{"201":{"content":{"application/json":{"schema":{"$ref":"#/components/schemas/Order"}}},"description":"Created"}},"summary":"Create an order"}},"/orders/{id}":{"get":{"deprecated":true,"operationId":"getOrder","parameters":[{"in":"path","name":"id","schema":{"type":"string"}}],"responses":{"200":{"content":{"application/json":{"schema":{"$ref":"#/components/schemas/Order"}}},"description":"The order"},"404":{"description":"Not found"}},"summary":"Fetch one order"}}},"security":[{"apiKey":[]}]}}'
# -> 402 Payment Required; read PAYMENT-REQUIRED
# retry the identical request with PAYMENT-SIGNATURE

JavaScript

const res = await fetch("https://api.zfinia.com/x402/v1/openapi-parameter-contract-audit", {
  "method": "POST",
  "headers": {
    "content-type": "application/json"
  },
  "body": "{\"request\":{\"headers\":{\"X-Api-Key\":\"redacted\"},\"method\":\"GET\",\"path\":\"/orders\",\"query\":{\"page\":\"first\"}},\"specification\":{\"components\":{\"schemas\":{\"Order\":{\"properties\":{\"id\":{\"type\":\"string\"},\"status\":{\"enum\":[\"open\",\"shipped\",\"disputed\"],\"type\":\"string\"},\"tenant_id\":{\"type\":\"string\"},\"total\":{\"type\":\"number\"}},\"required\":[\"id\",\"total\",\"tenant_id\"],\"type\":\"object\"}},\"securitySchemes\":{\"apiKey\":{\"in\":\"query\",\"name\":\"api_key\",\"type\":\"apiKey\"}}},\"info\":{\"title\":\"Orders API\",\"version\":\"2.0.0\"},\"openapi\":\"3.1.0\",\"paths\":{\"/orders\":{\"get\":{\"operationId\":\"listOrdersV2\",\"parameters\":[{\"in\":\"query\",\"name\":\"tenant\",\"required\":true,\"schema\":{\"type\":\"string\"}}],\"responses\":{\"200\":{\"content\":{\"application/json\":{\"schema\":{\"items\":{\"$ref\":\"#/components/schemas/Order\"},\"type\":\"array\"}}},\"description\":\"A page of orders\"}},\"summary\":\"List orders\"},\"parameters\":[{\"in\":\"query\",\"name\":\"page\",\"schema\":{\"minimum\":1,\"type\":\"integer\"}}],\"post\":{\"operationId\":\"createOrder\",\"requestBody\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"required\":true},\"responses\":{\"201\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"description\":\"Created\"}},\"summary\":\"Create an order\"}},\"/orders/{id}\":{\"get\":{\"deprecated\":true,\"operationId\":\"getOrder\",\"parameters\":[{\"in\":\"path\",\"name\":\"id\",\"schema\":{\"type\":\"string\"}}],\"responses\":{\"200\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"description\":\"The order\"},\"404\":{\"description\":\"Not found\"}},\"summary\":\"Fetch one order\"}}},\"security\":[{\"apiKey\":[]}]}}"
});
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
import json
res = httpx.request("POST", "https://api.zfinia.com/x402/v1/openapi-parameter-contract-audit", json=json.loads("{\"request\":{\"headers\":{\"X-Api-Key\":\"redacted\"},\"method\":\"GET\",\"path\":\"/orders\",\"query\":{\"page\":\"first\"}},\"specification\":{\"components\":{\"schemas\":{\"Order\":{\"properties\":{\"id\":{\"type\":\"string\"},\"status\":{\"enum\":[\"open\",\"shipped\",\"disputed\"],\"type\":\"string\"},\"tenant_id\":{\"type\":\"string\"},\"total\":{\"type\":\"number\"}},\"required\":[\"id\",\"total\",\"tenant_id\"],\"type\":\"object\"}},\"securitySchemes\":{\"apiKey\":{\"in\":\"query\",\"name\":\"api_key\",\"type\":\"apiKey\"}}},\"info\":{\"title\":\"Orders API\",\"version\":\"2.0.0\"},\"openapi\":\"3.1.0\",\"paths\":{\"/orders\":{\"get\":{\"operationId\":\"listOrdersV2\",\"parameters\":[{\"in\":\"query\",\"name\":\"tenant\",\"required\":true,\"schema\":{\"type\":\"string\"}}],\"responses\":{\"200\":{\"content\":{\"application/json\":{\"schema\":{\"items\":{\"$ref\":\"#/components/schemas/Order\"},\"type\":\"array\"}}},\"description\":\"A page of orders\"}},\"summary\":\"List orders\"},\"parameters\":[{\"in\":\"query\",\"name\":\"page\",\"schema\":{\"minimum\":1,\"type\":\"integer\"}}],\"post\":{\"operationId\":\"createOrder\",\"requestBody\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"required\":true},\"responses\":{\"201\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"description\":\"Created\"}},\"summary\":\"Create an order\"}},\"/orders/{id}\":{\"get\":{\"deprecated\":true,\"operationId\":\"getOrder\",\"parameters\":[{\"in\":\"path\",\"name\":\"id\",\"schema\":{\"type\":\"string\"}}],\"responses\":{\"200\":{\"content\":{\"application/json\":{\"schema\":{\"$ref\":\"#/components/schemas/Order\"}}},\"description\":\"The order\"},\"404\":{\"description\":\"Not found\"}},\"summary\":\"Fetch one order\"}}},\"security\":[{\"apiKey\":[]}]}}"))
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: api.zfinia.com
Endpoint: https://api.zfinia.com/x402/v1/openapi-parameter-contract-audit
Machine-readable: /resources/34029.json