# agent402.tools LLM Premium Inference (o3/o3-mini)

> agent402.tools LLM Premium Inference (o3/o3-mini) is a paid API for AI agents from agent402.tools, paid per call via x402, $0.5/call, status unknown (last checked 2026-09-14).

Proxies requests to OpenAI o3 or o3-mini reasoning models with vision and structured output support, paid per-call via x402 micropayment protocol

## Facts

- Endpoint: POST https://agent402.tools/api/llm-premium
- Price: $0.5/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/agent402-tools-llm-premium-inference-o3-o3-mini-eb1b211c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_soxbwwUphbrPbgP8AFfu-

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 agent402-tools-llm-premium-inference-o3-o3-mini-eb1b211c -d '<json body>'
```

Example prompt: Use the o3-mini reasoning model to analyze this image (https://example.com/chart.png) and return a JSON object with fields 'summary' and 'key_insights' — keep the output under 512 tokens.

## When to prefer this

Choose this endpoint when you need OpenAI's o3 or o3-mini reasoning models without managing your own OpenAI API key or billing, and want to pay per-call via x402. Ideal for agent workflows that need occasional high-quality reasoning or vision analysis without a subscription. Prefer over the standard tier when you need o3's deeper chain-of-thought reasoning. Choose over self-hosted alternatives when you want zero credential management.

## Known failure modes

- Payment not attached or insufficient USDC — x402 payment required before response is served
- Input exceeds 32k character cap — request rejected
- max_tokens exceeds 2048 cap — clamped or rejected
- Invalid model ID (not 'o3' or 'o3-mini') — model not found error
- Malformed image URL or more than 2 image URLs provided — vision input error
- Invalid response_format schema — structured output generation fails
- Model timeout on complex reasoning tasks — upstream timeout returned

## How this service works

LLM inference proxy (Premium tier) - o3 or o3-mini reasoning models. Supports vision (up to 2 image URLs) and structured output (response_format: json_object or json_schema). No API key needed; pay per call via x402. Input capped at 32k chars, output at 2048 tokens.

## Output

Returns a completion response from the o3 or o3-mini model, optionally structured as a JSON object or validated against a provided JSON schema. Includes the generated text content and up to 2048 output tokens. Supports multi-turn message arrays with interleaved text and image inputs.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "stop": {
   "type": "string",
   "description": "Stop sequence(s)"
  },
  "model": {
   "type": "string",
   "description": "Model ID - o3 or o3-mini"
  },
  "top_p": {
   "type": "number",
   "description": "Nucleus sampling (0-1)"
  },
  "messages": {
   "type": "array",
   "description": "Array of {role, content} objects. content can be a string or array of {type:'text',text} and {type:'image_url',image_url:{url,detail}} blocks"
  },
  "max_tokens": {
   "type": "number",
   "description": "Max output tokens (default 1024, cap 2048)"
  },
  "temperature": {
   "type": "number",
   "description": "Sampling temperature (0-2)"
  },
  "response_format": {
   "type": "object",
   "description": "Optional: {type:\"json_object\"} or {type:\"json_schema\",json_schema:{name,schema}}"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "model": "o3-mini",
  "usage": {
   "total_tokens": 20,
   "prompt_tokens": 12,
   "completion_tokens": 8
  },
  "choices": [
   {
    "message": {
     "role": "assistant",
     "content": "Hello! How can I help you today?"
    },
    "finish_reason": "stop"
   }
  ],
  "provider": "openai"
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/agent402-tools-llm-premium-inference-o3-o3-mini-eb1b211c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from agent402.tools](https://www.zero.xyz/host/agent402.tools/llms.txt)