## Create a new chat

`client.chats.create(ChatCreateParamsbody, RequestOptionsoptions?): ChatCreateResponse`

**post** `/v3/chats`

Create a new chat with specified participants and send an initial message.
The initial message is required when creating a chat.

## Message Effects

You can add iMessage effects to make your messages more expressive. Effects are
optional and can be either screen effects (full-screen animations) or bubble effects
(message bubble animations).

**Screen Effects:** `confetti`, `fireworks`, `lasers`, `sparkles`, `celebration`,
`hearts`, `love`, `balloons`, `happy_birthday`, `echo`, `spotlight`

**Bubble Effects:** `slam`, `loud`, `gentle`, `invisible`

Only one effect type can be applied per message.

## Inline Text Decorations (iMessage only)

Use the `text_decorations` array on a text part to apply styling and animations to character ranges.

Each decoration specifies a `range: [start, end)` and exactly one of `style` or `animation`.

**Styles:** `bold`, `italic`, `strikethrough`, `underline`
**Animations:** `big`, `small`, `shake`, `nod`, `explode`, `ripple`, `bloom`, `jitter`

```json
{
  "type": "text",
  "value": "Hello world",
  "text_decorations": [
    { "range": [0, 5], "style": "bold" },
    { "range": [6, 11], "animation": "shake" }
  ]
}
```

**Note:** Style ranges (bold, italic, etc.) may overlap, but animation ranges must not overlap with other animations or styles. Text decorations only render for iMessage recipients.
For SMS/RCS, text decorations are not applied.

## First-Message Link Restriction

To protect sender deliverability, the **first outbound message** of a new chat cannot be a link.
The request is rejected with `400` (error code `1005`) when:

- The message contains a `link` part (explicit rich-preview link), or
- Any `text` part contains a URL.

This rule applies only to `POST /v3/chats`. Follow-up messages on an existing chat
(`POST /v3/chats/{chatId}/messages`) are not subject to this restriction.

### Parameters

- `body: ChatCreateParams`

  - `from: string`

    Sender phone number in E.164 format. Must be a phone number that the
    authenticated partner has permission to send from.

  - `message: MessageContent`

    Message content container. Groups all message-related fields together,
    separating the "what" (message content) from the "where" (routing fields like from/to).

    - `parts: Array<TextPart | MediaPart | LinkPart>`

      Array of message parts. Each part can be text, media, or link.
      Parts are displayed in order. Text and media can be mixed freely,
      but a `link` part must be the only part in the message.

      **Rich Link Previews:**

      - Use a `link` part to send a URL with a rich preview card
      - A `link` part must be the **only** part in the message
      - To send a URL as plain text (no preview), use a `text` part instead

      **Supported Media:**

      - Images: .jpg, .jpeg, .png, .gif, .heic, .heif, .tif, .tiff, .bmp
      - Videos: .mp4, .mov, .m4v, .mpeg, .mpg, .3gp
      - Audio: .m4a, .mp3, .aac, .caf, .wav, .aiff, .amr
      - Documents: .pdf, .txt, .rtf, .csv, .doc, .docx, .xls, .xlsx, .ppt, .pptx, .pages, .numbers, .key, .epub, .zip, .html, .htm
      - Contact & Calendar: .vcf, .ics

      **Audio:**

      - Audio files (.m4a, .mp3, .aac, .caf, .wav, .aiff, .amr) are fully supported as media parts
      - To send audio as an **iMessage voice memo bubble** (inline playback UI), use the dedicated
        `/v3/chats/{chatId}/voicememo` endpoint instead

      **Validation Rules:**

      - A `link` part must be the **only** part in the message. It cannot be combined
        with text or media parts.
      - Consecutive text parts are not allowed. Text parts must be separated by
        media parts. For example, [text, text] is invalid, but [text, media, text] is valid.
      - Maximum of **100 parts** total.
      - Media parts using a public `url` (downloaded by the server on send) are
        capped at **40**. Parts using `attachment_id` or presigned URLs
        are exempt from this sub-limit. For bulk media sends exceeding 40 files,
        pre-upload via `POST /v3/attachments` and reference by `attachment_id` or `download_url`.

      - `TextPart`

        - `type: "text"`

          Indicates this is a text message part

          - `"text"`

        - `value: string`

          The text content of the message. This value is sent as-is with no parsing or transformation — Markdown syntax will be delivered as plain text. Use `text_decorations` to apply inline formatting and animations (iMessage only).

        - `text_decorations?: Array<TextDecoration>`

          Optional array of text decorations applied to character ranges in the `value` field (iMessage only).

          Each decoration specifies a character range `[start, end)` and exactly one of `style` or `animation`.

          **Styles:** `bold`, `italic`, `strikethrough`, `underline`
          **Animations:** `big`, `small`, `shake`, `nod`, `explode`, `ripple`, `bloom`, `jitter`

          Style ranges may overlap (e.g. bold + italic on the same text), but animation ranges must not overlap with other animations or styles.

          *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.*

          **Note:** Text decorations only render for iMessage recipients. For SMS/RCS, text decorations are not applied.

          - `range: Array<number>`

            Character range `[start, end)` in the `value` string where the decoration applies.
            `start` is inclusive, `end` is exclusive.
            *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.*

          - `animation?: "big" | "small" | "shake" | 5 more`

            Animated text effect to apply. Mutually exclusive with `style`.

            - `"big"`

            - `"small"`

            - `"shake"`

            - `"nod"`

            - `"explode"`

            - `"ripple"`

            - `"bloom"`

            - `"jitter"`

          - `style?: "bold" | "italic" | "strikethrough" | "underline"`

            Text style to apply. Mutually exclusive with `animation`.

            - `"bold"`

            - `"italic"`

            - `"strikethrough"`

            - `"underline"`

      - `MediaPart`

        - `type: "media"`

          Indicates this is a media attachment part

          - `"media"`

        - `attachment_id?: string`

          Reference to a file pre-uploaded via `POST /v3/attachments` (optional).
          The file is already stored, so sends using this ID skip the download step —
          useful when sending the same file to many recipients.

          Either `url` or `attachment_id` must be provided, but not both.

        - `url?: string`

          Any publicly accessible HTTPS URL to the media file. The server downloads and
          sends the file automatically — no pre-upload step required.

          **Size limit:** 10MB maximum for URL-based downloads. For larger files (up to 100MB),
          use the pre-upload flow: `POST /v3/attachments` to get a presigned URL, upload directly,
          then reference by `attachment_id`.

          **Requirements:**

          - URL must use HTTPS
          - File content must be a supported format (the server validates the actual file content)

          **Supported formats:**

          - Images: .jpg, .jpeg, .png, .gif, .heic, .heif, .tif, .tiff, .bmp
          - Videos: .mp4, .mov, .m4v, .mpeg, .mpg, .3gp
          - Audio: .m4a, .mp3, .aac, .caf, .wav, .aiff, .amr
          - Documents: .pdf, .txt, .rtf, .csv, .doc, .docx, .xls, .xlsx, .ppt, .pptx, .pages, .numbers, .key, .epub, .zip, .html, .htm
          - Contact & Calendar: .vcf, .ics

          **Tip:** Audio sent here appears as a regular file attachment. To send audio as an
          iMessage voice memo bubble (with inline playback), use `/v3/chats/{chatId}/voicememo`.
          For repeated sends of the same file, use `attachment_id` to avoid redundant downloads.

          Either `url` or `attachment_id` must be provided, but not both.

      - `LinkPart`

        - `type: "link"`

          Indicates this is a rich link preview part

          - `"link"`

        - `value: string`

          URL to send with a rich link preview. The recipient will see an inline card
          with the page's title, description, and preview image (when available).

          A `link` part must be the **only** part in the message. To send a URL as plain
          text (no preview card), use a `text` part instead.

    - `effect?: MessageEffect`

      iMessage effect to apply to this message (screen or bubble effect)

      - `name?: string`

        Name of the effect. Common values:

        - Screen effects: confetti, fireworks, lasers, sparkles, celebration, hearts, love, balloons, happy_birthday, echo, spotlight
        - Bubble effects: slam, loud, gentle, invisible

      - `type?: "screen" | "bubble"`

        Type of effect

        - `"screen"`

        - `"bubble"`

    - `idempotency_key?: string`

      Optional idempotency key for this message.
      Use this to prevent duplicate sends of the same message.

    - `preferred_service?: ServiceType`

      Messaging service type

      - `"iMessage"`

      - `"SMS"`

      - `"RCS"`

    - `reply_to?: ReplyTo`

      Reply to another message to create a threaded conversation

      - `message_id: string`

        The ID of the message to reply to

      - `part_index?: number`

        The specific message part to reply to (0-based index).
        Defaults to 0 (first part) if not provided.
        Use this when replying to a specific part of a multipart message.

  - `to: Array<string>`

    Array of recipient handles (phone numbers in E.164 format or email addresses).
    For individual chats, provide one recipient. For group chats, provide multiple.

### Returns

- `ChatCreateResponse`

  Response for creating a new chat with an initial message

  - `chat: Chat`

    - `id: string`

      Unique identifier for the created chat (UUID)

    - `display_name: string | null`

      Display name for the chat. Defaults to a comma-separated list of recipient handles. Can be updated for group chats.

    - `handles: Array<ChatHandle>`

      List of participants in the chat. Always contains at least two handles (your phone number and the other participant).

      - `id: string`

        Unique identifier for this handle

      - `handle: string`

        Phone number (E.164) or email address of the participant

      - `joined_at: string`

        When this participant joined the chat

      - `service: ServiceType`

        Messaging service type

        - `"iMessage"`

        - `"SMS"`

        - `"RCS"`

      - `is_me?: boolean | null`

        Whether this handle belongs to the sender (your phone number)

      - `left_at?: string | null`

        When they left (if applicable)

      - `status?: "active" | "left" | "removed" | null`

        Participant status

        - `"active"`

        - `"left"`

        - `"removed"`

    - `health_status: HealthStatus`

      **[BETA]** Current health for a chat. Always present — chats start at `HEALTHY` and may shift based on engagement and delivery signals on the conversation. Many `AT_RISK` or `CRITICAL` chats on a single line increase the risk of line flagging.

      Switch on `status` to gate sends or surface line health in your UI — the enum is the long-term contract. Each status carries a `doc_url` that deep-links to the relevant section of the Chat Health guide.

      See the [Chat Health guide](/guides/chats/chat-health) for what each status means and how to react.

      - `doc_url: string`

        Deep-link to the relevant section of the Chat Health guide for this status.

      - `status: "HEALTHY" | "AT_RISK" | "CRITICAL" | "OPTED_OUT"`

        Current health bucket for the chat. See the [Chat Health guide](/guides/chats/chat-health) for what each value means and how to react. `doc_url` deep-links to the relevant section.

        - `"HEALTHY"`

        - `"AT_RISK"`

        - `"CRITICAL"`

        - `"OPTED_OUT"`

      - `updated_at: string`

        When this status last changed.

    - `is_group: boolean`

      Whether this is a group chat

    - `message: SentMessage`

      A message that was sent (used in CreateChat and SendMessage responses)

      - `id: string`

        Message identifier (UUID)

      - `created_at: string`

        When the message was created

      - `delivery_status: "pending" | "queued" | "sent" | 2 more`

        Current delivery status of a message

        - `"pending"`

        - `"queued"`

        - `"sent"`

        - `"delivered"`

        - `"failed"`

      - `is_read: boolean`

        Whether the message has been read

      - `parts: Array<TextPartResponse | MediaPartResponse | LinkPartResponse>`

        Message parts in order (text, media, and link)

        - `TextPartResponse`

          A text message part

          - `reactions: Array<Reaction> | null`

            Reactions on this message part

            - `handle: ChatHandle`

              - `id: string`

                Unique identifier for this handle

              - `handle: string`

                Phone number (E.164) or email address of the participant

              - `joined_at: string`

                When this participant joined the chat

              - `service: ServiceType`

                Messaging service type

              - `is_me?: boolean | null`

                Whether this handle belongs to the sender (your phone number)

              - `left_at?: string | null`

                When they left (if applicable)

              - `status?: "active" | "left" | "removed" | null`

                Participant status

            - `is_me: boolean`

              Whether this reaction is from the current user

            - `type: ReactionType`

              Type of reaction. Standard iMessage tapbacks are love, like, dislike, laugh, emphasize, question.
              Custom emoji reactions have type "custom" with the actual emoji in the custom_emoji field.
              Sticker reactions have type "sticker" with sticker attachment details in the sticker field.

              - `"love"`

              - `"like"`

              - `"dislike"`

              - `"laugh"`

              - `"emphasize"`

              - `"question"`

              - `"custom"`

              - `"sticker"`

            - `custom_emoji?: string | null`

              Custom emoji if type is "custom", null otherwise

            - `sticker?: Sticker | null`

              Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions.

              - `file_name?: string`

                Filename of the sticker

              - `height?: number`

                Sticker image height in pixels

              - `mime_type?: string`

                MIME type of the sticker image

              - `url?: string`

                Presigned URL for downloading the sticker image (expires in 1 hour).

              - `width?: number`

                Sticker image width in pixels

          - `type: "text"`

            Indicates this is a text message part

            - `"text"`

          - `value: string`

            The text content

          - `text_decorations?: Array<TextDecoration> | null`

            Text decorations applied to character ranges in the value

            - `range: Array<number>`

              Character range `[start, end)` in the `value` string where the decoration applies.
              `start` is inclusive, `end` is exclusive.
              *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.*

            - `animation?: "big" | "small" | "shake" | 5 more`

              Animated text effect to apply. Mutually exclusive with `style`.

              - `"big"`

              - `"small"`

              - `"shake"`

              - `"nod"`

              - `"explode"`

              - `"ripple"`

              - `"bloom"`

              - `"jitter"`

            - `style?: "bold" | "italic" | "strikethrough" | "underline"`

              Text style to apply. Mutually exclusive with `animation`.

              - `"bold"`

              - `"italic"`

              - `"strikethrough"`

              - `"underline"`

        - `MediaPartResponse`

          A media attachment part

          - `id: string`

            Unique attachment identifier

          - `filename: string`

            Original filename

          - `mime_type: string`

            MIME type of the file

          - `reactions: Array<Reaction> | null`

            Reactions on this message part

            - `handle: ChatHandle`

            - `is_me: boolean`

              Whether this reaction is from the current user

            - `type: ReactionType`

              Type of reaction. Standard iMessage tapbacks are love, like, dislike, laugh, emphasize, question.
              Custom emoji reactions have type "custom" with the actual emoji in the custom_emoji field.
              Sticker reactions have type "sticker" with sticker attachment details in the sticker field.

            - `custom_emoji?: string | null`

              Custom emoji if type is "custom", null otherwise

            - `sticker?: Sticker | null`

              Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions.

          - `size_bytes: number`

            File size in bytes

          - `type: "media"`

            Indicates this is a media attachment part

            - `"media"`

          - `url: string`

            Presigned URL for downloading the attachment (expires in 1 hour).

        - `LinkPartResponse`

          A rich link preview part

          - `reactions: Array<Reaction> | null`

            Reactions on this message part

            - `handle: ChatHandle`

            - `is_me: boolean`

              Whether this reaction is from the current user

            - `type: ReactionType`

              Type of reaction. Standard iMessage tapbacks are love, like, dislike, laugh, emphasize, question.
              Custom emoji reactions have type "custom" with the actual emoji in the custom_emoji field.
              Sticker reactions have type "sticker" with sticker attachment details in the sticker field.

            - `custom_emoji?: string | null`

              Custom emoji if type is "custom", null otherwise

            - `sticker?: Sticker | null`

              Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions.

          - `type: "link"`

            Indicates this is a rich link preview part

            - `"link"`

          - `value: string`

            The URL

      - `sent_at: string | null`

        When the message was actually sent (null if still queued)

      - `delivered_at?: string | null`

        When the message was delivered

      - `effect?: MessageEffect | null`

        iMessage effect applied to a message (screen or bubble effect)

        - `name?: string`

          Name of the effect. Common values:

          - Screen effects: confetti, fireworks, lasers, sparkles, celebration, hearts, love, balloons, happy_birthday, echo, spotlight
          - Bubble effects: slam, loud, gentle, invisible

        - `type?: "screen" | "bubble"`

          Type of effect

          - `"screen"`

          - `"bubble"`

      - `from_handle?: ChatHandle | null`

        The sender of this message as a full handle object

      - `preferred_service?: ServiceType | null`

        Messaging service type

      - `reply_to?: ReplyTo | null`

        Indicates this message is a threaded reply to another message

        - `message_id: string`

          The ID of the message to reply to

        - `part_index?: number`

          The specific message part to reply to (0-based index).
          Defaults to 0 (first part) if not provided.
          Use this when replying to a specific part of a multipart message.

      - `service?: ServiceType | null`

        Messaging service type

    - `service: ServiceType`

      Messaging service type

### Example

```typescript
import LinqAPIV3 from '@linqapp/sdk';

const client = new LinqAPIV3({
  apiKey: process.env['LINQ_API_V3_API_KEY'], // This is the default and can be omitted
});

const chat = await client.chats.create({
  from: '+12052535597',
  message: { parts: [{ type: 'text', value: 'Hello! How can I help you today?' }] },
  to: ['+12052532136'],
});

console.log(chat.chat);
```

#### Response

```json
{
  "chat": {
    "id": "94c6bf33-31d9-40e3-a0e9-f94250ecedb9",
    "display_name": "+14155551234, +14155559876",
    "handles": [
      {
        "id": "550e8400-e29b-41d4-a716-446655440010",
        "handle": "+14155551234",
        "joined_at": "2025-05-21T15:30:00.000Z",
        "service": "iMessage",
        "is_me": true,
        "left_at": "2019-12-27T18:11:19.117Z",
        "status": "active"
      },
      {
        "id": "550e8400-e29b-41d4-a716-446655440011",
        "handle": "+14155559876",
        "joined_at": "2025-05-21T15:30:00.000Z",
        "service": "iMessage",
        "is_me": false,
        "left_at": "2019-12-27T18:11:19.117Z",
        "status": "active"
      }
    ],
    "health_status": {
      "doc_url": "https://docs.linqapp.com/guides/chats/chat-health#at-risk",
      "status": "AT_RISK",
      "updated_at": "2026-05-01T18:28:25Z"
    },
    "is_group": false,
    "message": {
      "id": "69a37c7d-af4f-4b5e-af42-e28e98ce873a",
      "created_at": "2025-10-23T13:07:55.019-05:00",
      "delivery_status": "pending",
      "is_read": false,
      "parts": [
        {
          "reactions": [
            {
              "handle": {
                "id": "69a37c7d-af4f-4b5e-af42-e28e98ce873a",
                "handle": "+15551234567",
                "joined_at": "2025-05-21T15:30:00.000-05:00",
                "service": "iMessage",
                "is_me": false,
                "left_at": "2019-12-27T18:11:19.117Z",
                "status": "active"
              },
              "is_me": false,
              "type": "love",
              "custom_emoji": null,
              "sticker": {
                "file_name": "sticker.png",
                "height": 420,
                "mime_type": "image/png",
                "url": "https://cdn.linqapp.com/attachments/a1b2c3d4/sticker.png?signature=...",
                "width": 420
              }
            }
          ],
          "type": "text",
          "value": "Hello!",
          "text_decorations": [
            {
              "range": [
                0,
                5
              ],
              "animation": "shake",
              "style": "bold"
            }
          ]
        }
      ],
      "sent_at": null,
      "delivered_at": null,
      "effect": {
        "name": "confetti",
        "type": "screen"
      },
      "from_handle": {
        "id": "550e8400-e29b-41d4-a716-446655440000",
        "handle": "+15551234567",
        "joined_at": "2025-05-21T15:30:00.000-05:00",
        "service": "iMessage",
        "is_me": false,
        "left_at": "2019-12-27T18:11:19.117Z",
        "status": "active"
      },
      "preferred_service": "iMessage",
      "reply_to": {
        "message_id": "550e8400-e29b-41d4-a716-446655440000",
        "part_index": 0
      },
      "service": "iMessage"
    },
    "service": "iMessage"
  }
}
```
