> ## Documentation Index
> Fetch the complete documentation index at: https://docs.apiyi.com/llms.txt
> Use this file to discover all available pages before exploring further.

# GPT-5.6 Sol

> GPT-5.6 Sol on APIYI: $4 input / $20 output per 1M tokens, 1,000,000 context, available in 4 billing groups.

The flagship tier of the GPT-5.6 family: 88.8% on Terminal-Bench 2.1 and 90.4% on BrowseComp; the `gpt-5.6` alias points here.

## Specifications

| Item | Value |
| - | - |
| **Model ID** | `gpt-5.6-sol` |
| **Vendor** | OpenAI |
| **Available on APIYI** | 2026-07-10 |
| **Knowledge cutoff** | Not disclosed |
| **Input modalities** | Text, Image |
| **Output modalities** | Text |
| **Context window** | 1,000,000 tokens |
| **Billing** | Usage-based |

## Pricing

Prices in USD per 1M tokens (\$/1M).

| Input | Cached input | Output |
| - | - | - |
| \$4 | \$0.4 | \$20 |

<Info>The table shows **list prices**. Recharge promotions and group discounts **stack**; the console reflects the actual charge in real time. See [Pricing](/en/pricing) and [Recharge promotions](/en/faq/recharge-promotions).</Info>

## Tiered pricing

This model is tier-priced by the token size of each request (output price = tier input price × output multiplier):

* 0 – 272,000 tokens: \$4/1M input
* Above 272,000 tokens: \$8/1M input

## Endpoints

| Endpoint | Path | Supported |
| - | - | - |
| `OpenAI Chat Completions` | `POST /v1/chat/completions` | ✅ |
| `OpenAI Responses` | `POST /v1/responses` | ✅ |
| `Anthropic Messages` | `POST /v1/messages` | — |
| `Gemini Generate Content` | `POST /v1beta/models/{model}:generateContent` | — |
| `Image Generations` | `POST /v1/images/generations` | — |
| `Embeddings` | `POST /v1/embeddings` | — |

## Billing groups

| Group | Multiplier | Notes |
| - | - | - |
| `CodexResponses` | 1× | List price |
| `Codex_Reverse` | 0.5× | 50% of list price |
| `Default` | 1× | List price |
| `SVIP` | 1× | List price |

Some groups carry extra discounts, stackable with recharge bonuses. See [Tokens and groups](/en/faq/token-and-groups).

## Supported features

| Feature | Supported |
| - | - |
| Streaming | ✅ |
| Tool calling | ✅ |
| Structured outputs | ✅ |
| Vision | ✅ |
| Prompt caching | ✅ |
| Extended thinking | Opt-in |

## Example request

The example below calls `gpt-5.6-sol` through OpenAI Chat Completions (`/v1/chat/completions`). Point base\_url at `https://api.apiyi.com/v1` — everything else matches the official API.

```bash theme={null}
curl https://api.apiyi.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer $APIYI_API_KEY" \
  -d '{
    "model": "gpt-5.6-sol",
    "messages": [{"role": "user", "content": "Hello"}]
  }'
```

<Tip>Read the key from an environment variable, never hard-coded. In production, issue separate tokens per use case so you can revoke and attribute usage individually.</Tip>

## Related docs

<CardGroup cols={2}>
  <Card title="Launch announcement" icon="megaphone" href="/en/news/gpt-5-6-launch">
    Background, benchmarks and migration notes for GPT-5.6 Sol
  </Card>

  <Card title="Compatible Mode" icon="book-open" href="/en/api-capabilities/openai/compatible">
    Parameters, usage and best practices
  </Card>

  <Card title="GPT-5.6 Terra" icon="git-compare" href="/en/models/gpt-5-6-terra">
    Details for a model in the same family
  </Card>

  <Card title="GPT-5.6 Luna" icon="git-compare" href="/en/models/gpt-5-6-luna">
    Details for a model in the same family
  </Card>

  <Card title="Model pricing directory" icon="table" href="/en/models">
    Live pricing, endpoints and groups for all models
  </Card>
</CardGroup>

<Note>Specs on this page are maintained by hand in `models/data/model-details.json`; pricing and endpoints come from the live pricing API and are refreshed with every rebuild.</Note>


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