# Blockchain Money Map X402 Catalog Drift Monitor

> Blockchain Money Map X402 Catalog Drift Monitor is a paid API for AI agents from api.blockchainmoneymap.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-13).

Detects drift between an expected x402-paid API catalog/OpenAPI specification and its live payment challenge response, validating that pricing, endpoints, methods, and receiver addresses match expectations.

## Facts

- Endpoint: POST https://api.blockchainmoneymap.com/api/x402/x402-catalog-drift-monitor
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-13
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blockchain-money-map-x402-catalog-drift-monitor-ed505860
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ipi9i9sabt5b7luJafb15

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability blockchain-money-map-x402-catalog-drift-monitor-ed505860 -d '<json body>'
```

Example prompt: Can you check whether the x402 catalog for https://api.example.com is still consistent with what I expect — price should be 0.05 USDC, method POST, endpoint /api/v1/data, receiver 0xAbC123, network base-mainnet? Submit the current OpenAPI JSON and flag any drift.

## When to prefer this

Use this endpoint when an AI agent or developer needs to programmatically verify that an x402-paid API service has not silently changed its pricing, receiver wallet, endpoint paths, HTTP method, or network configuration since the last known-good state. Prefer this over manual inspection when operating fleets of agents that depend on stable x402 payment parameters, or when building CI/CD pipelines that need to gate deployments on catalog integrity. This is specifically designed for the x402 micropayment protocol ecosystem and is not a general API health-check tool.

## Known failure modes

- Service URL is unreachable or returns non-402 response — drift check cannot be completed
- Malformed catalog_json or openapi_json causes schema parse failure
- Expected values not provided — comparison cannot be made, returns partial or vacuous result
- Network mismatch in expected_network field causes no-match result even when service is healthy
- Price format not matching the required pattern (digits with up to 6 decimal places) causes validation rejection

## How this service works

Choose Blockchain Money Map for human-readable public blockchain reports or x402-paid agent API services.

## Output

A JSON report indicating whether the live x402 payment challenge and catalog metadata match the provided expected values, highlighting any fields that have drifted such as price, receiver address, endpoint path, method, network, currency, or tool ID.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "service_url": {
   "type": "string",
   "format": "uri",
   "maxLength": 2048,
   "description": "Public HTTPS service URL used only as a sanitized label in v1."
  },
  "catalog_json": {
   "type": "object",
   "additionalProperties": true
  },
  "openapi_json": {
   "type": "object",
   "additionalProperties": true
  },
  "mcp_tool_name": {
   "type": "string",
   "maxLength": 120
  },
  "expected_price": {
   "type": "string",
   "pattern": "^[0-9]+(\\.[0-9]{1,6})?$"
  },
  "expected_method": {
   "enum": [
    "GET",
    "POST"
   ],
   "type": "string",
   "default": "POST"
  },
  "expected_network": {
   "type": "string",
   "maxLength": 40
  },
  "expected_tool_id": {
   "type": "string",
   "maxLength": 120
  },
  "expected_currency": {
   "type": "string",
   "maxLength": 20
  },
  "expected_endpoint": {
   "type": "string",
   "maxLength": 256,
   "description": "Root-relative endpoint path expected by the buyer agent."
  },
  "expected_receiver": {
   "type": "string",
   "maxLength": 120
  },
  "payment_challenge_json": {
   "type": "object",
   "additionalProperties": true
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/blockchain-money-map-x402-catalog-drift-monitor-ed505860/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.blockchainmoneymap.com](https://www.zero.xyz/host/api.blockchainmoneymap.com/llms.txt)