# x402 Health Check – Coding Agent Context APIs

> x402 Health Check – Coding Agent Context APIs is a paid API for AI agents from x402-canary.nicolas-x402-16f380a7.workers.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Checks whether a given URL is a reachable, valid x402 pay-per-call endpoint and returns protocol validity, latency, network, and canonical USDC configuration details.

## Facts

- Endpoint: POST https://x402-canary.nicolas-x402-16f380a7.workers.dev/v1/x402/health
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-health-check-coding-agent-context-apis-26db5395
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_RhJ35LlWsakepXhBiAr7k

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-health-check-coding-agent-context-apis-26db5395 -d '<json body>'
```

Example prompt: Can you check if https://x402.payai.network/api/base/paid-content is a reachable and valid x402 endpoint — tell me its protocol version, whether it's on Base mainnet, and if canonical USDC is correctly configured?

## When to prefer this

Use this endpoint when you need to programmatically verify that a specific URL implements the x402 pay-per-call protocol correctly before integrating it into an agent workflow, listing it on a marketplace, or triggering a payment. Prefer this over generic HTTP health checks when you specifically need x402 protocol validity, Base mainnet confirmation, USDC canonical config, or bazaar listing status.

## Known failure modes

- URL is unreachable — reachable: false returned with no latency
- Target URL returns non-402 status — protocol_valid: false
- Endpoint is not on Base mainnet — base_mainnet: false
- Resource does not match target URL — resource_matches_target: false
- Invalid URL format in input — request validation error
- Network timeout reaching the target URL

## How this service works

Free need-to-tool routing plus pay-per-call npm docs and TypeScript API signatures, npm breaking-change diffs, JavaScript-rendered browser snapshots and deterministic coding-agent checks via AgentCash/x402.

## Output

Returns a JSON object with a `data` field containing: HTTP status (402 expected), reachability boolean, latency in milliseconds, Base mainnet flag, x402 protocol version number, protocol validity boolean, bazaar declaration flag, canonical Base USDC flag, and resource-matches-target flag. Also includes a `meta.engine` field identifying the health engine used.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "format": "uri",
   "example": "https://x402.payai.network/api/base/paid-content"
  },
  "method": {
   "enum": [
    "GET",
    "POST"
   ],
   "type": "string",
   "default": "GET",
   "example": "GET"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "status": 402,
   "reachable": true,
   "latency_ms": 120,
   "base_mainnet": true,
   "x402_version": 2,
   "protocol_valid": true,
   "bazaar_declared": false,
   "canonical_base_usdc": true,
   "resource_matches_target": true
  },
  "meta": {
   "engine": "x402-health"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-health-check-coding-agent-context-apis-26db5395/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-canary.nicolas-x402-16f380a7.workers.dev](https://www.zero.xyz/host/x402-canary.nicolas-x402-16f380a7.workers.dev/llms.txt)