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

# GPT-5.5

> GPT-5.5 is OpenAI's flagship model for complex professional work, with text/image input, text output, 1.05M context, 128K max output, and Responses tool supp...

## Overview

GPT-5.5 is OpenAI's flagship model for complex professional work, with text/image input, text output, 1.05M context, 128K max output, and Responses tool support.

| Property | Value |
| - | - |
| Provider | OpenAI |
| Slug | `gpt-5-5` |
| Context | 1,000,000 tokens |
| Max output | 128,000 tokens |
| Input | text, image |
| Output | text |
| Release | 2026-04-27 |
| Tags | production |

## Capabilities

* `text`
* `vision`
* `image-input`
* `file-input`
* `pdf-input`
* `tool-calling`
* `function-calling`
* `structured-outputs`
* `json-mode`
* `streaming`
* `reasoning`
* `extended-thinking`
* `code-execution`
* `web-search`
* `code-generation`
* `long-context`
* `multilingual`
* `multimodal`

## Pricing

| Item | Price |
| - | - |
| Input (prompt) | \$5 |
| Output (completion) | \$30 |
| Cache read | \$0.5 |
| Cache write | - |

Prices are customer prices per **1M tokens** for a Hostlinku API key, with 1 kredit = \$1. Actual cost per request follows the API key's Service Mode and may change; check [Console](https://console.hostlinku.com/models) or `GET /v1/models` for current values.

## Supported endpoints

| Endpoint | Format | Support |
| - | - | - |
| `POST /v1/chat/completions` | OpenAI Chat Completions | available |
| `POST /v1/messages` | Anthropic Messages | adapted (bridge) |
| `POST /v1/responses` | OpenAI Responses | native |

Endpoint and model availability follow the catalog and the API key's Service Mode. If a model is unavailable for that mode, the request may be rejected with `400 MODEL_NOT_IN_SERVICE_MODE`.

## Example request

```bash theme={null}
curl https://api.hostlinku.com/v1/chat/completions \
  -H "Authorization: Bearer sk-isi-api-key-kamu" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "gpt-5-5",
    "messages": [{ "role": "user", "content": "Hello!" }]
  }'
```

## Related models

* [GPT 5.3 Codex](https://docs.hostlinku.com/en/models/gpt-5-3-codex.md)
* [GPT-5.6 Luna](https://docs.hostlinku.com/en/models/gpt-5-6-luna.md)
* [GPT-5.6 Sol](https://docs.hostlinku.com/en/models/gpt-5-6-sol.md)
* [GPT-5.6 Terra](https://docs.hostlinku.com/en/models/gpt-5-6-terra.md)
* [GPT-6 Astra](https://docs.hostlinku.com/en/models/gpt-6-astra.md)
* [GPT-6 Luna](https://docs.hostlinku.com/en/models/gpt-6-luna.md)

[← Back to the model catalog](https://docs.hostlinku.com/en/models.md)


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