# OpenAI o3-mini via mm.family (x402)

> OpenAI o3-mini via mm.family (x402) 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 OpenAI o3-mini reasoning model chat completions billed per-call in USDC via x402 micropayment protocol, with selectable reasoning effort levels (low/medium/high/xhigh).

## Facts

- Endpoint: POST https://openai.mm.family/x402/v1/models/o3-mini/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-o3-mini-via-mm-family-x402-8fe460b2
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_8RDndaYwmH2a4s028djdA

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-o3-mini-via-mm-family-x402-8fe460b2 -d '<json body>'
```

Example prompt: Use o3-mini with high reasoning effort to solve this logic puzzle: a farmer has 17 sheep, all but 9 die — how many are left? Explain your reasoning step by step and limit output to 500 tokens.

## When to prefer this

Choose this endpoint when you need OpenAI's o3-mini reasoning model with selectable effort levels (low to xhigh) and want to pay per-call in USDC via x402 without maintaining an OpenAI API subscription. Ideal for agents that need trustless, on-chain-friendly AI inference, or for tasks requiring deep multi-step reasoning where GPT-4o-class models underperform.

## Known failure modes

- Insufficient USDC balance causes x402 payment failure before completion
- max_tokens quota too low results in truncated output with finish_reason=length
- Invalid model variant string (e.g. typo in o3-mini:level) returns 400 error
- Empty or malformed messages array causes request rejection
- Overloaded service tier may increase latency or return 503
- Empty response (zero completion tokens) is billed as free

## How this service works

o3-mini: OpenAI o3 Mini chat completions, paid per call in USDC. Per 1M tokens in/out: Standard (default) 1.1/4.4; pick with service_tier. Plus $0.0005 (Base) or $0.0005 (Solana) per call; the quote charges input plus 10% of max_tokens. Levels: low, medium, high, xhigh (model o3-mini:<level>). 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 reply message, token usage breakdown (prompt, completion, total), finish reason, model used, and service tier applied.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "model": {
   "enum": [
    "o3-mini",
    "o3-mini:low",
    "o3-mini:medium",
    "o3-mini:high",
    "o3-mini:xhigh"
   ],
   "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": "o3-mini",
  "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-o3-mini-via-mm-family-x402-8fe460b2/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)