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

# GPT 5.4

> OpenAI's GPT 5.4 language model

GPT 5.4 is OpenAI's flagship general-purpose language model for complex reasoning, coding, and analysis tasks.

## Model

```
openai/gpt-5.4
```

|              |         |
| ------------ | ------- |
| **Provider** | OpenAI  |
| **Name**     | GPT 5.4 |

## Supported Endpoints

All three API formats are supported:

* [Chat Completions](/api-reference/v1-chat-completions) — `POST /v1/chat/completions`
* [Responses](/api-reference/v1-responses) — `POST /v1/responses`
* [Messages](/api-reference/v1-messages) — `POST /v1/messages`

## Example

```bash theme={null}
curl -X POST https://api.unifically.com/v1/chat/completions \
  -H "Content-Type: application/json" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -d '{
    "model": "openai/gpt-5.4",
    "messages": [
      {"role": "user", "content": "Design a REST API for a todo application."}
    ]
  }'
```