# GPT-5.4 API

> GPT-5.4 — frontier reasoning and generation through one API.

- **Provider**: OpenAI
- **Model id**: `gpt-5-4`
- **Modality**: text
- **Price**: 127.43–869.44 credits

## Overview

GPT-5.4 is called in ONE step: POST your request and the answer comes back in the same response, in `text`. There is no task to poll.

## Authentication

All requests require a Bearer Token in the request header:

```
Authorization: Bearer YOUR_API_KEY
```

## Create Task

`POST https://you.bot/api/v1/generate`

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| modelId | string | Yes | Model id: `gpt-5-4` |
| input | object | Yes | Input parameters object (see below) |
| callbackUrl | string | No | https URL we POST the finished task to. Signed with `X-Webhook-Signature` once you create a webhook signing key in Dashboard → Settings |

### input object parameters

| Parameter | Type | Required | Description |
|-----------|------|----------|-------------|
| prompt | string | Yes | Text value |
| memory | boolean | No | Automatically append previous messages to maintain multi-turn context. May increase token usage. (true/false) (default: false) |
| reasoning_effort | string | No | Control reasoning depth: Low for faster responses, High for deeper analysis (options: Low \| Medium \| High \| XHigh) (default: Medium) |
| stream | boolean | No | Send true to receive the reply as an event stream (Content-Type: text/event-stream). Omit it and you get a single JSON response — streaming is opt-in on this endpoint. (true/false) (example: true) |
| system | string | No | System instruction for the model. Defaults to "You are GPT-5.4, developed by OpenAI." when omitted. |
| messages | array | No | A conversation instead of a single `prompt`: up to 20 objects of { "role", "content" }, where role is user, assistant or system. Send `prompt` or `messages`, not both. Do not flatten a conversation into one prompt with "User:" / "Assistant:" labels — the model reads that as a single message, and a model using web search then searches for the whole block instead of your question. |

### Request example

```json
{
  "modelId": "gpt-5-4",
  "input": {
    "prompt": "Explain how diffusion models generate images, in two short sentences.",
    "memory": false,
    "reasoning_effort": "Medium",
    "stream": true
  }
}
```

### Response example

```json
{
  "taskId": "281e5b0…f39b9",
  "creditsCharged": 24
}
```

## Query Task

`GET https://you.bot/api/v1/task/{taskId}?model=gpt-5-4`

When `state` is `success`, the output is in `resultUrls`: `{ "text": "…" }`. (Text models return inline in the create response.)

## Error Codes

| Code | Description |
|------|-------------|
| 200 | Request successful |
| 400 | Invalid request parameters |
| 401 | Authentication failed — check API Key |
| 402 | Insufficient account balance |
| 403 | IP not allowed for this key, or the key is restricted to other models |
| 404 | Task not found, or it has expired |
| 409 | Duplicate request — an identical submit arrived moments ago. Nothing was charged; retry is safe |
| 413 | Payload too large — see the character and file-size limits for this model |
| 429 | Rate limit exceeded — retry after the Retry-After header |
| 500 | Internal server error |
| 504 | Upstream timed out — nothing was delivered; retry is safe |
| 400 · capability_not_supported | A capability was requested (e.g. `web_search: true`) that this model does not offer — refused, nothing charged |
| 400 · unknown_image_field | Images were sent under a key this model has no parameter for (input_urls, image_urls, imageUrl …) — refused rather than answered without them |
| 400 · image_input_not_supported | This model accepts text only — a request with an image is refused, not answered without it |