# x402 Radar Conformance Probe

> x402 Radar Conformance Probe is a paid API for AI agents from ali-acids-helmet-cindy.trycloudflare.com, paid per call via x402, $0.002/call, status down (last checked 2026-10-02).

Checks whether a given URL implements a valid x402 payment handshake and returns its price, asset, network, payTo address, and latency.

## Facts

- Endpoint: GET https://ali-acids-helmet-cindy.trycloudflare.com/api/check?utm_source=zero.xyz
- Price: $0.002/call
- Payment: x402
- Status: down
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-radar-conformance-probe-29b60c53
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_65odyzQZ0RAOuzm-yXik6

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-radar-conformance-probe-29b60c53
```

Example prompt: Before I send any payment, check whether https://api.exa.ai/search is a valid x402 endpoint — tell me if it returns a proper 402 handshake, what it charges, which network and asset it uses, and the payTo address.

## When to prefer this

Use this endpoint when you need to verify that a specific URL correctly implements the x402 payment protocol before committing to a payment, or when you want to discover the live pricing, network, and payment address of any x402-gated service. Prefer this over static registry lookups when you need real-time conformance and latency data rather than indexed metadata.

## Known failure modes

- Target URL is unreachable — alive=false, x402=false
- Target URL returns 200/404 instead of 402 — x402=false, valid_handshake=false
- URL is x402 but handshake is malformed — x402=true, valid_handshake=false
- High latency or timeout on target endpoint — latency_ms may be very large or missing
- Invalid or missing URL input — probe cannot run, error response
- Non-USDC asset — price_usd_if_usdc may be null or 0

## How this service works

Live x402 conformance probe: url=<endpoint>, returns whether it serves a valid 402 handshake, actual price/asset/network/payTo, latency. Verify before you pay. By x402 Radar.

## Output

Returns a JSON object indicating whether the URL is alive, whether it responds with HTTP 402, whether the handshake is valid per x402 spec, the scheme, network (e.g. base), asset, payTo wallet address, price in atomic units and USD (if USDC), x402 version, and round-trip latency in milliseconds.

## 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"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string",
       "description": "REQUIRED. URL-encoded x402 endpoint to probe, e.g. https%3A%2F%2Fx402.payai.network%2Fapi%2Fbase%2Fpaid-content"
      }
     }
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object",
     "properties": {
      "at": {
       "type": "string"
      },
      "x402": {
       "type": "boolean"
      },
      "alive": {
       "type": "boolean"
      },
      "asset": {
       "type": "string"
      },
      "payTo": {
       "type": "string"
      },
      "scheme": {
       "type": "string"
      },
      "status": {
       "type": "number"
      },
      "checked": {
       "type": "string"
      },
      "network": {
       "type": "string"
      },
      "latency_ms": {
       "type": "number"
      },
      "price_atomic": {
       "type": "string"
      },
      "x402_version": {
       "type": "number"
      },
      "valid_handshake": {
       "type": "boolean"
      },
      "price_usd_if_usdc": {
       "type": "number"
      }
     }
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "example": {
  "x402": true,
  "alive": true,
  "scheme": "exact",
  "status": 402,
  "checked": "https://api.exa.ai/search",
  "network": "base",
  "latency_ms": 340,
  "valid_handshake": true,
  "price_usd_if_usdc": 0.007
 },
 "properties": {
  "at": {
   "type": "string"
  },
  "x402": {
   "type": "boolean"
  },
  "alive": {
   "type": "boolean"
  },
  "asset": {
   "type": "string"
  },
  "payTo": {
   "type": "string"
  },
  "scheme": {
   "type": "string"
  },
  "status": {
   "type": "number"
  },
  "checked": {
   "type": "string"
  },
  "network": {
   "type": "string"
  },
  "latency_ms": {
   "type": "number"
  },
  "price_atomic": {
   "type": "string"
  },
  "x402_version": {
   "type": "number"
  },
  "valid_handshake": {
   "type": "boolean"
  },
  "price_usd_if_usdc": {
   "type": "number"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-radar-conformance-probe-29b60c53/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from ali-acids-helmet-cindy.trycloudflare.com](https://www.zero.xyz/host/ali-acids-helmet-cindy.trycloudflare.com/llms.txt)