# Swift Bot Labs x402 Check

> Swift Bot Labs x402 Check is a paid API for AI agents from x402-toolbox.swiftbotlab.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-31).

Checks whether a given URL is a live, valid x402 pay-per-call endpoint and returns its payment parameters, pricing, and health status.

## Facts

- Endpoint: GET https://x402-toolbox.swiftbotlab.workers.dev/v1/x402/check?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/swift-bot-labs-x402-check-6b4c365d
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_gTNNDdgkLnYCEOJi3lQXa

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 swift-bot-labs-x402-check-6b4c365d
```

Example prompt: Can you check if https://api.bitrefill.com/x402/gift-cards/search is a valid x402 endpoint — is it alive, does it accept USDC, and what does it cost per call?

## When to prefer this

Use this endpoint when you need to programmatically verify whether a URL implements the x402 pay-per-call protocol before attempting a payment, when auditing a list of APIs for x402 compliance, or when you need to extract payment parameters (wallet address, chain, price) from an unknown endpoint without manually inspecting HTTP headers. It is the definitive probe tool for the x402 ecosystem and requires no API key — pay $0.01 USDC per check.

## Known failure modes

- Target URL is unreachable or times out — alive: false returned
- URL does not return HTTP 402 — isX402: false with issues listed
- Malformed URL in query parameter — validation error returned
- Target endpoint returns 402 but with non-conformant x402 headers — issues array populated
- Network error from Cloudflare Worker reaching the target — error response with ok: false

## How this service works

62 small, deterministic utility APIs (DNS and e-mail checks, web extraction, EVM decoding, x402 checks, IP math, JSON/CSV, hashing, conversions). No account or API key: pay per call in USDC with x402.

## Output

A JSON object with: ok (boolean), tool name, and a result object containing the target URL, whether it is alive, whether it is listed on the bazaar, whether it is a valid x402 endpoint, any detected issues, the HTTP status code, an array of accepted payment options (chain, payTo address, scheme, network, priceUsd, assetSymbol), round-trip latency in milliseconds, and the x402 protocol version.

## 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",
      "HEAD"
     ],
     "type": "string"
    },
    "headers": {
     "type": "object",
     "additionalProperties": {
      "type": "string"
     }
    },
    "queryParams": {
     "type": "object",
     "required": [
      "url"
     ],
     "properties": {
      "url": {
       "type": "string"
      },
      "method": {
       "enum": [
        "GET",
        "POST",
        "HEAD"
       ],
       "type": "string"
      }
     },
     "additionalProperties": false
    },
    "discoverable": {
     "type": "boolean"
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "ok": true,
  "tool": "x402-check",
  "result": {
   "url": "https://api.bitrefill.com/x402/gift-cards/search",
   "alive": true,
   "bazaar": true,
   "isX402": true,
   "issues": [],
   "status": 402,
   "accepts": [
    {
     "chain": "Base",
     "payTo": "0x...",
     "scheme": "exact",
     "network": "eip155:8453",
     "priceUsd": 0.002,
     "assetSymbol": "USDC"
    }
   ],
   "latencyMs": 210,
   "x402Version": 2
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/swift-bot-labs-x402-check-6b4c365d/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-toolbox.swiftbotlab.workers.dev](https://www.zero.xyz/host/x402-toolbox.swiftbotlab.workers.dev/llms.txt)