# X402-BROKER x402 Verifier

> X402-BROKER x402 Verifier is a paid API for AI agents from mcp-gateway.agentdiet.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-22).

Verifies and validates x402 payment-gated HTTP endpoints, returning structured proof of access and compression metadata

## Facts

- Endpoint: GET https://mcp-gateway.agentdiet.dev/v1/x402-verifier?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-broker-x402-verifier-04b60a3a
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_-rZH7dKJEQqB8__i8FL1-

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 x402-broker-x402-verifier-04b60a3a
```

Example prompt: Can you verify that the x402 endpoint at https://api.example.com/data is live and accessible using a GET request, and show me the compression ratio proof?

## When to prefer this

Use this endpoint when you need to deterministically verify that an x402-gated HTTP endpoint is live, accessible, and returning valid data before routing agent or payment traffic to it. Prefer this over generic HTTP probing tools when you specifically need x402 protocol compliance validation and ROI compression proof metadata.

## Known failure modes

- Invalid or unreachable URL returns non-ok status
- Unsupported HTTP method causes validation error
- Missing required 'url' query parameter causes schema rejection
- x402 payment failure returns 402 status
- Endpoint timeout or network error returns failure status
- Malformed response from target endpoint causes parse error

## How this service works

Deterministic B2A/A2A/MCP/x402/MPP/L402 execution and intelligence node at https://mcp-gateway.agentdiet.dev settling in USDC on Base.

## Output

Returns a JSON object with a status field ('ok' or error), a data object containing the endpoint response payload, and a roi_proof object including a compression_ratio_pct value indicating how efficiently the endpoint's data was compressed.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET",
      "POST"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {
      "url": {
       "type": "string"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {},
  "status": "ok",
  "roi_proof": {
   "compression_ratio_pct": 91.4
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-broker-x402-verifier-04b60a3a/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from mcp-gateway.agentdiet.dev](https://www.zero.xyz/host/mcp-gateway.agentdiet.dev/llms.txt)