# Faro x402 Payment Support Checker

> Faro x402 Payment Support Checker is a paid API for AI agents from byfaro.ai, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).

Checks whether a website supports x402 HTTP payment protocol and agent-commerce payment discovery, returning a yes/no verdict plus detailed sub-checks and remediation hints.

## Facts

- Endpoint: POST https://byfaro.ai/agent/check/x402
- 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/faro-x402-payment-support-checker-2b48cbad
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_oDJ9sYvWqgMWVz3oUtH-K

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 faro-x402-payment-support-checker-2b48cbad -d '<json body>'
```

Example prompt: Before I try to buy something from acme-api.com, check whether it supports x402 payments so my agent knows if it can pay autonomously.

## When to prefer this

Use this endpoint when an AI agent needs to determine before attempting a purchase whether a target website is capable of receiving autonomous x402 payments — especially useful in agentic shopping workflows, API integration vetting, and debugging payment failures. Prefer this focused x402 check over Faro's full 47-point audit when you only need the payment-readiness signal quickly and cheaply.

## Known failure modes

- Invalid or unreachable URL returns an error with no scan results
- URL missing scheme (not absolute) causes validation failure
- Site behind firewall or CAPTCHA may return inconclusive results
- Timeouts on slow-responding sites may yield incomplete sub-checks
- False negatives if x402 signals are dynamically injected client-side

## How this service works

Single-signal check: can AI agents pay this website? Detects x402 support, /.well-known payment discovery and agent-commerce readiness. Returns yes/no plus underlying checks and fixes. Useful before attempting autonomous purchase from a site.

## Output

Returns a boolean yes/no verdict on whether the site is x402-ready, along with granular sub-check results covering x402 HTTP header support, /.well-known payment discovery endpoint presence, and agent-commerce readiness signals, plus actionable fixes for any failed checks.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "url": {
   "type": "string",
   "description": "Absolute URL of the website to scan, e.g. https://example.com"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/faro-x402-payment-support-checker-2b48cbad/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from byfaro.ai](https://www.zero.xyz/host/byfaro.ai/llms.txt)