# OpenAI GPT-4.1 Chat Completions (x402/USDC)

> OpenAI GPT-4.1 Chat Completions (x402/USDC) is a paid API for AI agents from openai.mm.family, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Runs GPT-4.1 chat completions via a pay-per-call USDC gateway using the x402 payment protocol, with configurable service tiers (standard, fast, flex).

## Facts

- Endpoint: POST https://openai.mm.family/x402/v1/models/gpt-4.1/chat/completions?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/openai-gpt-4-1-chat-completions-x402-usdc-de902e98
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_72ZO_t4UhQFvM26fBxeCu

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 openai-gpt-4-1-chat-completions-x402-usdc-de902e98 -d '<json body>'
```

Example prompt: Using the GPT-4.1 model on the mm.family x402 gateway with standard service tier, answer this multi-turn conversation: the system says 'You are a helpful assistant' and the user asks 'What are three key differences between supervised and unsupervised learning?' — limit the response to 500 tokens.

## When to prefer this

Choose this endpoint when you need GPT-4.1 quality chat completions and want to pay per-call in USDC without managing an OpenAI API key or subscription — ideal for crypto-native agents, x402-compatible wallets, or workflows where on-chain micropayments are required. Prefer the 'standard' tier for cost efficiency or 'fast' for lower latency. If you need a cheaper model, prefer gpt-4.1-nano; for the latest model alias, prefer chat-latest.

## Known failure modes

- Insufficient USDC balance or failed x402 payment — request rejected before inference
- max_tokens set too high causes quote to exceed available balance
- Unsupported service_tier value returns validation error
- Malformed messages array (missing 'role' or 'content') causes 400 error
- Model unavailable or rate-limited on the upstream OpenAI side — 503 or 429 propagated
- Streaming mode (stream:true) may require specific client handling not supported by all x402 clients

## How this service works

gpt-4.1: OpenAI GPT 4.1 chat completions, paid per call in USDC. Per 1M tokens in/out: Standard (default) 2.0/8.0, Fast 3.5/14.0; pick with service_tier. Plus $0.0005 (Base) or $0.0005 (Solana) per call; the quote charges input plus 10% of max_tokens. Empty answers are free. Rates: https://openai.mm.family/x402/pricing

## Output

Returns a standard OpenAI-compatible chat completion JSON object containing the assistant's message text, finish reason (e.g. 'stop'), token usage breakdown (prompt, completion, total), model name, and the service tier that was applied. Empty responses when the answer is empty are provided at no charge.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "enum": [
    "gpt-4.1"
   ],
   "type": "string"
  },
  "tools": {
   "type": "array"
  },
  "stream": {
   "type": "boolean"
  },
  "messages": {
   "type": "array",
   "items": {
    "type": "object",
    "required": [
     "role",
     "content"
    ],
    "properties": {
     "role": {
      "type": "string"
     },
     "content": {
      "type": "string"
     }
    }
   }
  },
  "max_tokens": {
   "type": "integer"
  },
  "service_tier": {
   "enum": [
    "flex",
    "default",
    "standard",
    "auto",
    "fast",
    "priority"
   ],
   "type": "string"
  },
  "response_format": {
   "type": "object"
  },
  "reasoning_effort": {
   "type": "string"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "id": "chatcmpl-x",
  "model": "gpt-4.1",
  "usage": {
   "total_tokens": 9,
   "prompt_tokens": 8,
   "completion_tokens": 1
  },
  "object": "chat.completion",
  "choices": [
   {
    "index": 0,
    "message": {
     "role": "assistant",
     "content": "Hello",
     "refusal": null
    },
    "finish_reason": "stop"
   }
  ],
  "service_tier": "default"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/openai-gpt-4-1-chat-completions-x402-usdc-de902e98/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from openai.mm.family](https://www.zero.xyz/host/openai.mm.family/llms.txt)