# P402Protocol Demo

## Building

### POST
https://api.p402.io/v1/agent/inference

### SEND

### Headers

- Content-Type: application/json
- X-Agent-ID: did:p402:agent:1234...

### Body

```
{
  "task": "complex_reasoning",
  "model": "llama-3-70b-instruct",
  "max_tokens": 1024
}
```

Negotiating...

- REQUEST: 402
- PAY
- RETRY
- RECEIPT REUSE
- AUDIT

Agent requests service. Gateway discovers cost.

[Build Your First Payment Flow →](/content/demo/payment-flow/index.html)