## First page of a chat

`GET /v1/chats/:dialogId/messages/initial`

Returns the page of messages that the messenger shows when it opens a chat — the v2 messenger method `im.v2.Chat.Message.list`. The page is built around the "unread" mark or, when there is none, around the last read message. Use it to open a chat where the user left off, without a separate request for the chat itself; the chat together with pinned messages comes from [loading a chat](/docs/chats/messages/load).

## Parameters

| Parameter | Type | Required | Default | Description |
|----------|-----|:-----:|-----------|---------|
| `dialogId` (path) | string | yes | — | Dialog ID: numeric user ID for personal messages, `chatXXX` for group chats. The `me` alias addresses the current user's personal dialog. The user's dialogs are in the [list of recent dialogs](/docs/chats/discovery/recent) (`GET /v1/chats/recent`) |
| `limit` (query) | number | no | 50 | How many messages to take on each side of the anchor message. From 1 to 200: an out-of-range value is clamped and echoed in `meta.requestedLimit` and `meta.appliedLimit` |
| `ignoreMark` (query) | boolean | no | `false` | `true` — build the page around the last read message, ignoring the "unread" mark |

Any other parameter or a repeated parameter is rejected with `400 INVALID_PARAMS`.

## Examples

### curl — personal key

```bash
curl "https://vibecode.bitrix24.com/v1/chats/chat42/messages/initial?limit=20" \
  -H "X-Api-Key: YOUR_API_KEY"
```

### curl — OAuth application

```bash
curl "https://vibecode.bitrix24.com/v1/chats/chat42/messages/initial?limit=20" \
  -H "X-Api-Key: YOUR_APP_KEY" \
  -H "Authorization: Bearer USER_SESSION_TOKEN"
```

### JavaScript — personal key

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/chat42/messages/initial?limit=20', {
  headers: { 'X-Api-Key': 'YOUR_API_KEY' },
})

const { data } = await res.json()
console.log('Messages:', data.messages.map((m) => m.id), 'has older:', data.hasPrevPage)
```

### JavaScript — OAuth application

```javascript
const res = await fetch('https://vibecode.bitrix24.com/v1/chats/chat42/messages/initial?limit=20', {
  headers: {
    'X-Api-Key': 'YOUR_APP_KEY',
    'Authorization': 'Bearer USER_SESSION_TOKEN',
  },
})

const { data } = await res.json()
console.log('Messages:', data.messages.map((m) => m.id), 'has older:', data.hasPrevPage)
```

## Response fields

| Field | Type | Description |
|------|-----|---------|
| `success` | boolean | Always `true` on success |
| `data.messages` | array | Messages on the page, from oldest to newest |
| `data.messages[].id` | number | Message ID |
| `data.messages[].chatId` | number | Chat ID |
| `data.messages[].authorId` | number | Author ID. `0` — a system message |
| `data.messages[].date` | string | Send date (ISO 8601) |
| `data.messages[].text` | string | Message text |
| `data.messages[].unread` | boolean | Not read by the current user |
| `data.messages[].viewed` | boolean | Viewed by the current user |
| `data.messages[].viewedByOthers` | boolean | Viewed by one of the members |
| `data.additionalMessages` | array | Messages that the page's messages reply to, when they are not on the page themselves |
| `data.users` | array | Authors of the page's messages |
| `data.usersShort` | array | Short profiles of the page's users |
| `data.files` | array | Files of the page's messages |
| `data.reactions` | array | Reactions to the page's messages |
| `data.stickers` | array | Stickers of the page's messages |
| `data.tariffRestrictions.isHistoryLimitExceeded` | boolean | History older than the plan allows is hidden |
| `data.hasPrevPage` | boolean | There are messages older than the page |
| `data.hasNextPage` | boolean | There are messages newer than the page |
| `meta.requestedLimit` | number | The passed `limit`, when it falls outside the range from 1 to 200 |
| `meta.appliedLimit` | number | The applied `limit` value |

## Response example

```json
{
  "success": true,
  "data": {
    "messages": [
      {
        "id": 1001,
        "chatId": 42,
        "authorId": 5,
        "date": "2026-09-20T10:00:00+00:00",
        "text": "Please review the mockup",
        "params": {}
      },
      {
        "id": 1002,
        "chatId": 42,
        "authorId": 7,
        "date": "2026-09-20T10:01:00+00:00",
        "text": "All done",
        "params": {}
      }
    ],
    "additionalMessages": [],
    "users": [],
    "usersShort": [],
    "files": [],
    "reactions": [],
    "stickers": [],
    "tariffRestrictions": { "isHistoryLimitExceeded": false },
    "hasPrevPage": true,
    "hasNextPage": false
  }
}
```

## Error response example

422 — the chat does not exist in the Bitrix24 account:

```json
{
  "success": false,
  "error": {
    "code": "BITRIX_ERROR",
    "message": "CHAT_NOT_FOUND",
    "b24Code": "CHAT_NOT_FOUND"
  }
}
```

## Errors

| HTTP | Code | Description |
|------|-----|---------|
| 400 | `INVALID_PARAMS` | A parameter other than `limit` and `ignoreMark`, a repeated parameter or an invalid value. Checked before any call to Bitrix24 |
| 404 | `ENTITY_NOT_FOUND` | Bitrix24 returned the `NOT_FOUND` code; the portal code is in `error.b24Code` |
| 422 | `BITRIX_ERROR` | Bitrix24 returned an error; the portal code is in `error.b24Code`. A missing chat lands here too: `CHAT_NOT_FOUND` |
| 502 | `ME_ALIAS_RESOLUTION_FAILED` | Failed to resolve the user for the `me` alias |
| 403 | `BITRIX_ACCESS_DENIED` | The user has no access to the chat — Bitrix24 refused with the `ACCESS_DENIED` code |
| 403 | `SCOPE_DENIED` | The API key does not have the `im` scope |
| 403 | `WRITE_BLOCKED_READONLY_KEY` | `Message.list` grants Drive quick access, so a read-only key cannot call it; use [the v2 feed](/docs/chats/messages/list) |
| 401 | `TOKEN_MISSING` | The API key has no Bitrix24 tokens configured |

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

## Known specifics

**The initial page may change state.** Beyond conditional auto-join, `Message.list` grants quick access to Drive files. That is a separate side effect, so a `READONLY` key gets `403 WRITE_BLOCKED_READONLY_KEY`. [The v2 feed](/docs/chats/messages/list) supports the first page and pagination without that grant.

**The limit is per side.** `limit` sets the number of messages before the anchor message and after it, so the page can be almost twice the size of `limit`.

**Response keys.** Keys that name fields are converted to camelCase: the `FILE_ID` message parameter arrives as `fileId`. Keys that are data stay as they are: the `data.copilot.roles` dictionary is keyed by the role code, and `copilot_assistant` arrives as `copilot_assistant`.

**Continue in the message history.** Read older messages from the [message history in the v2 mode](/docs/chats/messages/list), passing `lastId` equal to the smallest `id` on the page, and newer ones with `order=asc` and `lastId` equal to the largest.

## See also

- [Load a chat](/docs/chats/messages/load)
- [Read messages](/docs/chats/messages/list)
- [Messages around a message](/docs/chats/messages/context)