# GPT-5.6 Luna

## Best for

High-volume GPT-5.6 chat, classification, and light agents

## When not to use

Image, audio, or video. Not GPT-5.6 Sol — use Sol for multi-step coding and long-horizon reasoning. Call it as `gpt-5.6-luna`.

## Overview

GPT-5.6 Luna is a fast, cost-efficient model in OpenAI's GPT-5.6 series. It is suited for high-volume, latency-sensitive tasks such as chat, classification, and lightweight agentic workflows, providing capable reasoning for its price tier.

| | |
| --- | --- |
| API identifier | `gpt-5.6-luna` |
| Developer | OpenAI |
| Context window | 262,144 tokens |
| Supports | text, reasoning, tool-use |
| Status | Serving |

## Rates

USD per 1M tokens, on-demand tier.

| Input | Cached input | Output |
| --- | --- | --- |
| $0.20 | $0.02 | $1.20 |

## Call it

Put `gpt-5.6-luna` in the `model` field. The same request works against the Anthropic Messages API — see [API Compatibility](https://inference.boundless.network/docs/api-compatibility).

```bash
curl https://api.inference.boundless.network/v1/chat/completions \
  -H "Authorization: Bearer $BOUNDLESS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5.6-luna",
    "messages": [{
      "content": "Say hello",
      "role": "user"
    }]
  }'
```

Every model we serve is listed at [Models](https://inference.boundless.network/models); the rate card in full is on [Pricing](https://inference.boundless.network/docs/pricing).