# Grok 4.5 API

> Grok 4.5 — frontier reasoning and generation through one API.

- **Provider**: Grok
- **Model id**: `grok-4-5`
- **Modality**: text
- **Price**: 75–225 credits

## Overview

Grok 4.5 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: `grok-4-5` |
| 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 (example: Explain quantum entanglement to a 10-year-old using a pair of magic gloves as the example. Keep it under 120 words.) |
| structured_outputs | boolean | No | Generate structured outputs (true/false) (example: false) |
| web_search | boolean | No | Web search feeds the results back as input tokens, so a searched turn typically costs many times a normal turn (measured: 6–87×). Billed per token as usual — nothing extra per search. (true/false) (example: false) |
| reasoning_effort | string | No | Control reasoning depth: Low for faster responses, High for deeper analysis (options: Low \| Medium \| High) (example: High) |
| 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) |
| max_tokens | number | No | Maximum response length in tokens, reasoning included. Leave empty for the default of 4,096. (range 1-128000) |
| system | string | No | System instruction for the model. Defaults to "You are Grok 4.5, developed by Grok." when omitted. |
| messages | array | No | A conversation instead of a single `prompt`: an array of { "role", "content" } objects, where role is user, assistant or system. Send the whole conversation — we do not limit how many messages it has, and we do not drop old ones; the model's context window is the limit. 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": "grok-4-5",
  "input": {
    "prompt": "Explain quantum entanglement to a 10-year-old using a pair of magic gloves as the example. Keep it under 120 words.",
    "structured_outputs": false,
    "web_search": false,
    "reasoning_effort": "High",
    "stream": false,
    "max_tokens": 4096
  }
}
```

### Response example

```json
{
  "model": "grok-4-5",
  "text": "…",
  "creditsCharged": 0.06,
  "usage": {
    "inputTokens": 1400,
    "outputTokens": 120,
    "cachedInputTokens": 1024,
    "cacheWriteTokens": 0
  }
}
```

## Query Task

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

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 |