# x402 Agent Payment Demo

> x402 Agent Payment Demo is a paid API for AI agents from x402-demo-production-19f3.up.railway.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-30).

Demonstrates the x402 HTTP payment protocol by serving a paid demo response requiring $0.01 USDC per GET request

## Facts

- Endpoint: GET https://x402-demo-production-19f3.up.railway.app/demo?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-30
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/x402-agent-payment-demo-79ae7c15
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_J71F0Do3sZqgdOTxgirnj

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-agent-payment-demo-79ae7c15
```

Example prompt: Call the x402 payment demo endpoint — it costs $0.01 USDC per request — and show me the response you get back after the payment goes through.

## When to prefer this

Choose this endpoint when you want to demonstrate, test, or validate the x402 HTTP micropayment protocol in action. It is ideal for developers building agent payment flows, verifying that a wallet or payment layer correctly handles HTTP 402 challenges, or showcasing pay-per-call AI agent infrastructure to stakeholders. Not suitable for production data retrieval or any use case beyond protocol demonstration.

## Known failure modes

- Payment proof missing or invalid — server returns HTTP 402 Payment Required
- Insufficient USDC balance — payment cannot be completed
- Network error reaching Railway-hosted endpoint — connection timeout
- Malformed x402 payment header — server rejects the request
- Stale or already-used payment proof — replay protection triggers rejection

## How this service works

x402 Agent payment proof of concept

## Output

A demo response payload returned after successful x402 micropayment verification, confirming the payment was accepted and the content gate was unlocked. The response demonstrates a working pay-per-call API interaction using the x402 HTTP payment protocol.

## Request schema (JSON Schema)

```json
{
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/x402-agent-payment-demo-79ae7c15/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from x402-demo-production-19f3.up.railway.app](https://www.zero.xyz/host/x402-demo-production-19f3.up.railway.app/llms.txt)