# FarOut GPT-5.4 Chat Completions via x402

> FarOut GPT-5.4 Chat Completions via x402 is a paid API for AI agents from farouter.tech, paid per call via x402, $0.00106/call, status unknown (last checked 2026-09-15).

Runs a GPT-5.4 chat completion request billed per-call in USDC via the x402 payment protocol — no API key or account required.

## Facts

- Endpoint: POST https://farouter.tech/v1/metered/models/gpt-5.4/chat/completions
- Price: $0.00106/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-15
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/farout-gpt-5-4-chat-completions-via-x402-7a752396
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_u4HXoM47Ls_izg4bV68Kh

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 farout-gpt-5-4-chat-completions-via-x402-7a752396 -d '<json body>'
```

Example prompt: Ask GPT-5.4 via FarOut — paying per call in USDC on Base — to explain the difference between proof-of-work and proof-of-stake in two paragraphs, keeping the tone friendly and accessible.

## When to prefer this

Choose this endpoint when you need GPT-5.4 inference without an OpenAI account or pre-funded API key, particularly in autonomous agent or crypto-native contexts where per-call USDC micropayments on Base or Solana are preferable to subscription billing. Ideal for agents that call LLMs sporadically and want zero-setup, pay-as-you-go access with the guarantee that failed calls are never charged.

## Known failure modes

- Payment insufficient or rejected — call not charged but request fails with 402
- Invalid or malformed messages array — 400 bad request
- Model identifier not recognized — endpoint returns error
- Network or blockchain congestion causes payment timeout
- Rate limiting or upstream OpenAI unavailability — 503 or 429 upstream error

## How this service works

Pay-per-call LLM inference over x402. Frontier models (GLM, GPT, Gemini, Kimi, DeepSeek, MiniMax) billed per request in USDC on Base or Solana mainnet. No API key, no account. The 402 quotes your exact request; failed calls are never charged.

## Output

A JSON object matching the OpenAI chat completions response format: an array of choices each containing the assistant message (role + content) and finish_reason, plus a usage object with prompt_tokens and completion_tokens counts.

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "usage": {
   "prompt_tokens": 6,
   "completion_tokens": 8
  },
  "choices": [
   {
    "message": {
     "role": "assistant",
     "content": "Hello! How can I help?"
    },
    "finish_reason": "stop"
   }
  ]
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/farout-gpt-5-4-chat-completions-via-x402-7a752396/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from farouter.tech](https://www.zero.xyz/host/farouter.tech/llms.txt)