## Upload file

`POST /v1/bots/:botId/files`

Uploads a file to a chat on behalf of the bot. The content is passed as base64. Maximum size: 100 MB.

## Request fields (body)

| Parameter | Type | Required | Description |
|----------|-----|:-----:|---------|
| `dialogId` | string | yes | Dialog ID: numeric user ID for direct chats, `chatXXX` for group chats |
| `file.name` | string | yes | File name with extension |
| `file.content` | string | yes | File content in base64 |
| `message` | string | no | Message text attached to the file |

## Examples

### curl — personal key

```bash
curl -X POST https://vibecode.bitrix24.com/v1/bots/42/files \
  -H "X-Api-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "dialogId": "chat123",
    "file": {
      "name": "report.pdf",
      "content": "JVBERi0xLjQKJcOkw7zDtsOfCjEgMCBv..."
    },
    "message": "Here is the requested report"
  }'
```

### curl — OAuth application

```bash
curl -X POST https://vibecode.bitrix24.com/v1/bots/42/files \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "dialogId": "chat123",
    "file": {
      "name": "report.pdf",
      "content": "JVBERi0xLjQKJcOkw7zDtsOfCjEgMCBv..."
    },
    "message": "Here is the requested report"
  }'
```

### JavaScript — personal key

```javascript
import { readFileSync } from 'fs'

const base64 = readFileSync('./report.pdf').toString('base64')

const res = await fetch('https://vibecode.bitrix24.com/v1/bots/42/files', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_API_KEY',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    dialogId: 'chat123',
    file: { name: 'report.pdf', content: base64 },
    message: 'Here is the requested report',
  }),
})

const { success, data } = await res.json()
console.log('File ID:', data.file.id)
```

### JavaScript — OAuth application

```javascript
import { readFileSync } from 'fs'

const base64 = readFileSync('./report.pdf').toString('base64')

const res = await fetch('https://vibecode.bitrix24.com/v1/bots/42/files', {
  method: 'POST',
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
    dialogId: 'chat123',
    file: { name: 'report.pdf', content: base64 },
    message: 'Here is the requested report',
  }),
})

const { success, data } = await res.json()
```

## Response fields

| Field | Type | Description |
|------|-----|---------|
| `file` | object | Uploaded file data |
| `file.id` | number | Uploaded file ID (use it for `GET /v1/bots/:botId/files/:fileId`) |
| `file.chatId` | number | Numeric chat ID |
| `file.name` | string | File name |
| `file.extension` | string | File extension |
| `file.size` | number | File size in bytes |
| `messageId` | number | ID of the created message with the file |
| `chatId` | number | Numeric chat ID |
| `dialogId` | string | Dialog ID |

## Response example

```json
{
  "success": true,
  "data": {
    "file": {
      "id": 789,
      "chatId": 5,
      "name": "report.pdf",
      "extension": "pdf",
      "size": 35341
    },
    "messageId": 1520,
    "chatId": 5,
    "dialogId": "chat123"
  }
}
```

## Error response example

502 — Bitrix24 error:

```json
{
  "success": false,
  "error": {
    "code": "BITRIX_ERROR",
    "message": "File size exceeds limit"
  }
}
```

## Errors

| HTTP | Code | Description |
|------|-----|---------|
| 400 | `INVALID_BOT_ID` | `botId` is not a number |
| 404 | `BOT_NOT_FOUND` | No bot with this ID found |
| 403 | `BOT_ACCESS_DENIED` | Bot belongs to a different API key |
| 502 | `BITRIX_ERROR` | Bitrix24 error during upload |
| 403 | `SCOPE_DENIED` | API key does not have the `imbot` scope |
| 401 | `TOKEN_MISSING` | API key has no configured tokens |

Full list of common API errors — [Errors](/docs/errors).

## Known specifics

**Base64:** the file content is passed in full as base64. For large files this increases the body size by ~33%.

**Message with the file:** the `message` parameter attaches text to the same message as the file — no separate call is needed to send the text.

## See also

- [Download file](/docs/bots/files/download)
- [Send message](/docs/bots/messages/send)
- [Bot platform](/docs/bots)
- [Limits and optimization](/docs/optimization)