## Send a message to an existing chat **post** `/v3/chats/{chatId}/messages` Send a message to an existing chat. Use this endpoint when you already have a chat ID and want to send additional messages to it. ## 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. Decorations render per recipient, not per message: in a group with both iMessage and SMS/RCS participants, iMessage recipients see the decorations and SMS/RCS recipients receive the same message as plain text. ### Path Parameters - `chatId: string` ### Body Parameters - `message: MessageContent` Message content container. Groups all message-related fields together, separating the "what" (message content) from the "where" (routing fields like from/to). A message carries EITHER `parts` — text and attachments, which compose into one bubble — or a single `experience` invocation, which renders an experience inside Linq's iMessage app. Never both: an app card is the whole message (Apple's `MSMessage` cannot coexist with text), so copy and a card are two sends, not one. - `effect: optional MessageEffect` iMessage effect to apply to this message (screen or bubble effect) - `name: optional 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: optional "screen" or "bubble"` Type of effect - `"screen"` - `"bubble"` - `experience: optional object { action, name, params }` Invokes an action on an experience — a third party that renders inside Linq's iMessage app. Linq resolves the recipient's connection, mints any session the action needs, composes the card and sends it; none of that is visible to you. Call `GET /v3/experiences/{experience}` for the actions you may invoke and the fields each accepts. - `action: string` Which of its actions, e.g. `attach_card`. - `name: string` The experience to invoke, e.g. `agentcard` or `agentpay`. - `params: optional map[unknown]` Values for the fields this action exposes. Keys are exactly the field names listed for the action — no mapping, no nesting. Display copy only, except a `url`-type field — that value sets the destination, and must be an absolute `https` URL. Some fields are read rather than sent: `agentpay`'s `request_payment` takes only a `checkout_url` and resolves the amount and reason from that payment request itself, so the card cannot state a figure the checkout will not charge. - `idempotency_key: optional string` Optional idempotency key for this message. Use this to prevent duplicate sends of the same message. Reusing a key whose message was deleted — or was an ephemeral message that has since expired — returns 404; the message is never resent. - `parts: optional array of TextPart or MediaPart or LinkPart or 2 more` 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 **App Clip Payment Cards:** - Use an `app_clip` part to send a Linq checkout link as an Apple Pay App Clip card (the payment preview with the Open button) - An `app_clip` part must be the **only** part in the message - iMessage-only: unlike `link`, it never downgrades to SMS/RCS — the send fails instead of delivering a bare URL **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. - An `app_clip` part must be the **only** part in the message. Its `value` must be a Linq checkout link (e.g. from `POST /v3/payment_requests`); any other URL is rejected. - 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 object { type, value, mention, 2 more }` - `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). - `mention: optional string` Mention a chat participant. Group chats only — sending a mention to a direct chat is rejected with `409` / `2023`. The chat's service is not a constraint: a mention is accepted in any group, including one with SMS/RCS participants. Set to their handle — E.164 phone number or Apple ID email. `value` is the display text; use the bare name (`"Juan"`, not `"@Juan"`). By default the entire `value` renders as the mention; use `mention_range` to highlight only part of it. Rendering is per recipient, not per message. iMessage recipients see the mention highlighted and are notified even if they have muted the chat. SMS and RCS recipients receive the same message as plain text — no highlight, and no mute override. One send, two experiences. - `mention_range: optional array of number` Optional character range `[start, end)` in `value` that renders as the `mention` highlight (e.g. just the name in `"Hey Kevin, can you look at this?"`). Requires `mention`. Without it, the entire `value` is highlighted. `start` is inclusive, `end` is exclusive. *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.* Applies to iMessage recipients only, matching `mention` — SMS and RCS recipients receive the text with no highlight. - `text_decorations: optional array of 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:** decorations render per recipient, not per message. In a group containing both iMessage and SMS/RCS participants, iMessage recipients see the decorations and SMS/RCS recipients receive the same message as plain text. - `range: array of 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: optional "big" or "small" or "shake" or 5 more` Animated text effect to apply. Mutually exclusive with `style`. - `"big"` - `"small"` - `"shake"` - `"nod"` - `"explode"` - `"ripple"` - `"bloom"` - `"jitter"` - `style: optional "bold" or "italic" or "strikethrough" or "underline"` Text style to apply. Mutually exclusive with `animation`. - `"bold"` - `"italic"` - `"strikethrough"` - `"underline"` - `MediaPart object { type, attachment_id, sticker, url }` - `type: "media"` Indicates this is a media attachment part - `"media"` - `attachment_id: optional 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. - `sticker: optional boolean` Send this image as a **sticker** rather than a photo. The recipient can peel it off and place it on any message in the conversation, and it renders without a bubble. An opaque photo is cut out automatically — the subject is lifted from its background, the same way "Add Sticker" does on iOS. An image that already has transparency is sent as-is. If no subject can be found, the image sends as an ordinary photo. **iMessage only.** On SMS/RCS the flag is ignored and the image sends as a photo. Stickers can be combined with a `text` part in the same message; the text arrives as its own bubble. To place a sticker *onto* an existing message instead, use `POST /v3/messages/{messageId}/reactions` with `type: "sticker"`. - `url: optional 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 object { type, value }` - `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. - `IMessageApp object { app, layout, type, 3 more }` An iMessage app card, backed by a Messages app extension. iMessage only — an `imessage_app` part must be the **only** part in the message and is never delivered over SMS/RCS. See the IMessageAppServiceUnsupported (2018) and RecipientUnsupportedMessageType (4005) error codes. - `app: object { bundle_id, name, team_id, app_store_id }` Identifies the iMessage app (Messages app extension) that backs the card. - `bundle_id: string` Bundle identifier of the Messages app extension. Must not contain `:`. - `name: string` Display name of the app, shown by Messages' fallback UI. - `team_id: string` The app's 10-character uppercase alphanumeric team identifier. - `app_store_id: optional number` The owning app's App Store id (optional). When set, recipients without the iMessage app installed see a "Get the app" affordance. - `layout: object { caption, image_subtitle, image_title, 4 more }` Visible layout of the card. At least one of `caption`, `subcaption`, `trailing_caption`, `trailing_subcaption`, or `image_url` must be set, otherwise the card renders as an empty bubble. `image_url` displays a preview image at the top of the card. The image renders on the recipient's card whether or not they have your app installed. The small icon beside the caption is the app's own icon and is not settable here. `* Note - requires a trusted chat w/ inbound activity` `image_title` and `image_subtitle` render as text overlaid on the image (title bold, subtitle beneath it). They only appear when `image_url` is set — without an image there is nothing to overlay — so setting either without `image_url` is rejected. - `caption: optional string` Primary label, top-left and bold. - `image_subtitle: optional string` Text shown below `image_title`, overlaid on the card image. Requires `image_url`. - `image_title: optional string` Bold text overlaid on the card image. Requires `image_url` (rejected without it). - `image_url: optional string` URL of an image (JPEG, PNG, HEIF, or WebP) to display as the card's preview image; an unreachable or non-image URL returns a validation error. Renders for all recipients regardless of whether they have the app. Note - requires a trusted chat w/ inbound activity. In responses, this is the re-hosted `cdn.linqapp.com` copy of the image you supplied, not your original URL. - `subcaption: optional string` Secondary label, below `caption` on the left. - `trailing_caption: optional string` Label shown top-right. - `trailing_subcaption: optional string` Label shown below `trailing_caption`, on the right. - `type: "imessage_app"` Indicates this is an iMessage app card part. - `"imessage_app"` - `fallback_text: optional string` Text shown on surfaces that cannot render the card (notifications, lock screen). Defaults to the caption when omitted. - `interactive: optional boolean` Whether the card renders as your app's interactive balloon for recipients who have your iMessage app installed. `true` (default) lets your installed extension draw its live, interactive view for those recipients; everyone else sees the static card built from `layout`. `false` always shows the static `layout` card, even to recipients who have the app installed. Recipients without your app always see the static card regardless of this flag. - `url: optional string` URL the recipient's app opens when they tap the card. Either an absolute `https://` URL (capped at 2048 characters) or a `data:` URL carrying inline app state, e.g. a game's encoded state (capped at 16384 characters). - `AppClip object { type, value, caption }` Sends a **registered App Clip** — not only Linq's Apple Pay checkout, but any partner's own App Clip. `caption` is optional. An `app_clip` part must be the **only** part in the message. **iMessage only**, and it never downgrades. A `service_preference` of `sms` or `rcs` is rejected (`AppClipServiceUnsupported`, 2028). A recipient who can't receive it fails the send rather than being sent a plain link in its place. - `type: "app_clip"` Indicates this is an App Clip card - `"app_clip"` - `value: string` An https link whose page is a registered App Clip — Linq's checkout link (e.g. the `checkout_url` from `POST /v3/payment_requests`) or a partner's own App Clip URL. A URL that doesn't resolve to a sendable App Clip page is rejected. - `caption: optional string` Optional caption for the card's **Open** button row. Omit it and the card uses the App Clip's own default (`Tap open`). Set it to override that with your own short call to action. - `preferred_service: optional ServiceType` Messaging service type - `"iMessage"` - `"SMS"` - `"RCS"` - `reply_to: optional ReplyTo` Reply to another message to create a threaded conversation - `message_id: string` The ID of the message to reply to - `part_index: optional 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. - `override_optout: optional boolean` Send even though the recipient asked you to stop (`403`, error code `2024`). Applies to this request only: the opt-out stays in place, so the next send without this flag is rejected again. Every override is recorded against your API key. ### Returns - `chat_id: string` Unique identifier of the chat this message was sent to - `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" or "queued" or "sent" or 4 more` Current delivery status of a message - `"pending"` - `"queued"` - `"sent"` - `"delivered"` - `"received"` - `"read"` - `"failed"` - `is_read: boolean` DEPRECATED: Use `delivery_status == "read"` instead. Whether the message has been read. - `parts: array of TextPartResponse or MediaPartResponse or LinkPartResponse or 2 more` Message parts in order (text, media, and link) - `TextPartResponse object { reactions, type, value, 4 more }` A text message part - `reactions: array of Reaction` 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 - `"iMessage"` - `"SMS"` - `"RCS"` - `is_me: optional boolean` Whether this handle belongs to the sender (your phone number) - `left_at: optional string` When they left (if applicable) - `status: optional "active" or "left" or "removed"` Participant status - `"active"` - `"left"` - `"removed"` - `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"` - `id: optional string` Identifier for this reaction. Pass it to `PATCH /v3/messages/{messageId}/reactions/{reactionId}` to move a sticker. Stickers placed before this API shipped can be read but not moved: the device-side reference needed to reposition them was never recorded, so `PATCH` returns 404 for those. - `custom_emoji: optional string` Custom emoji if type is "custom", null otherwise - `sticker: optional object { file_name, height, mime_type, 2 more }` Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions. - `file_name: optional string` Filename of the sticker - `height: optional number` Sticker image height in pixels - `mime_type: optional string` MIME type of the sticker image - `url: optional string` Presigned URL for downloading the sticker image (expires in 1 hour). - `width: optional number` Sticker image width in pixels - `type: "text"` Indicates this is a text message part - `"text"` - `value: string` The text content - `mention: optional string` DEPRECATED: Use `mentions` instead. Handle (E.164 phone number or Apple ID email) of the **first** mention on this part. A part may carry several mentions; this field shows only the first in `value` order, so it cannot be used to determine whether a given participant was mentioned. `null` when the part carries no mention. - `mention_range: optional array of number` DEPRECATED: Use `mentions[].range` instead. Character range `[start, end)` in `value` highlighted as the **first** mention only. `null` when the range was omitted (the whole `value` is highlighted) or the part carries no mention. *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.* - `mentions: optional array of object { handle, is_me, range }` Every mention on this part, in the order they appear in `value`. `null` when the part carries no mention. A part can carry several mentions of different people — check `is_me` to tell whether this line was one of them. Only iMessage carries mentions. On a received message this is populated when the sender was on iMessage; SMS and RCS have no way to mark a mention, so a message from an SMS or RCS participant arrives as plain text with `mentions` null, even in a group where other participants are on iMessage. - `handle: string` Address of the mentioned participant, exactly as the device recorded it — an E.164 phone number or an email address. - `is_me: boolean` Whether the mentioned participant is this line. - `range: array of number` Character range `[start, end)` in `value` highlighted as this mention. *Characters are measured as UTF-16 code units. Most characters count as 1; some emoji count as 2.* - `text_decorations: optional array of TextDecoration` Text decorations applied to character ranges in the value - `range: array of 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: optional "big" or "small" or "shake" or 5 more` Animated text effect to apply. Mutually exclusive with `style`. - `"big"` - `"small"` - `"shake"` - `"nod"` - `"explode"` - `"ripple"` - `"bloom"` - `"jitter"` - `style: optional "bold" or "italic" or "strikethrough" or "underline"` Text style to apply. Mutually exclusive with `animation`. - `"bold"` - `"italic"` - `"strikethrough"` - `"underline"` - `MediaPartResponse object { id, filename, mime_type, 4 more }` A media attachment part - `id: string` Unique attachment identifier - `filename: string` Original filename - `mime_type: string` MIME type of the file - `reactions: array of Reaction` 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. - `id: optional string` Identifier for this reaction. Pass it to `PATCH /v3/messages/{messageId}/reactions/{reactionId}` to move a sticker. Stickers placed before this API shipped can be read but not moved: the device-side reference needed to reposition them was never recorded, so `PATCH` returns 404 for those. - `custom_emoji: optional string` Custom emoji if type is "custom", null otherwise - `sticker: optional object { file_name, height, mime_type, 2 more }` 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 object { reactions, type, value }` A rich link preview part - `reactions: array of Reaction` 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. - `id: optional string` Identifier for this reaction. Pass it to `PATCH /v3/messages/{messageId}/reactions/{reactionId}` to move a sticker. Stickers placed before this API shipped can be read but not moved: the device-side reference needed to reposition them was never recorded, so `PATCH` returns 404 for those. - `custom_emoji: optional string` Custom emoji if type is "custom", null otherwise - `sticker: optional object { file_name, height, mime_type, 2 more }` 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 - `IMessageAppPartResponse object { app, layout, reactions, 3 more }` An iMessage app card part. - `app: object { bundle_id, name, team_id, app_store_id }` Identifies the iMessage app (Messages app extension) that backs the card. - `bundle_id: string` Bundle identifier of the Messages app extension. Must not contain `:`. - `name: string` Display name of the app, shown by Messages' fallback UI. - `team_id: string` The app's 10-character uppercase alphanumeric team identifier. - `app_store_id: optional number` The owning app's App Store id (optional). When set, recipients without the iMessage app installed see a "Get the app" affordance. - `layout: object { caption, image_subtitle, image_title, 4 more }` Visible layout of the card. At least one of `caption`, `subcaption`, `trailing_caption`, `trailing_subcaption`, or `image_url` must be set, otherwise the card renders as an empty bubble. `image_url` displays a preview image at the top of the card. The image renders on the recipient's card whether or not they have your app installed. The small icon beside the caption is the app's own icon and is not settable here. `* Note - requires a trusted chat w/ inbound activity` `image_title` and `image_subtitle` render as text overlaid on the image (title bold, subtitle beneath it). They only appear when `image_url` is set — without an image there is nothing to overlay — so setting either without `image_url` is rejected. - `caption: optional string` Primary label, top-left and bold. - `image_subtitle: optional string` Text shown below `image_title`, overlaid on the card image. Requires `image_url`. - `image_title: optional string` Bold text overlaid on the card image. Requires `image_url` (rejected without it). - `image_url: optional string` URL of an image (JPEG, PNG, HEIF, or WebP) to display as the card's preview image; an unreachable or non-image URL returns a validation error. Renders for all recipients regardless of whether they have the app. Note - requires a trusted chat w/ inbound activity. In responses, this is the re-hosted `cdn.linqapp.com` copy of the image you supplied, not your original URL. - `subcaption: optional string` Secondary label, below `caption` on the left. - `trailing_caption: optional string` Label shown top-right. - `trailing_subcaption: optional string` Label shown below `trailing_caption`, on the right. - `reactions: array of Reaction` 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. - `id: optional string` Identifier for this reaction. Pass it to `PATCH /v3/messages/{messageId}/reactions/{reactionId}` to move a sticker. Stickers placed before this API shipped can be read but not moved: the device-side reference needed to reposition them was never recorded, so `PATCH` returns 404 for those. - `custom_emoji: optional string` Custom emoji if type is "custom", null otherwise - `sticker: optional object { file_name, height, mime_type, 2 more }` Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions. - `type: "imessage_app"` Indicates this is an iMessage app card part. - `"imessage_app"` - `url: string` The URL delivered to the iMessage app on tap. - `fallback_text: optional string` Fallback text for surfaces that cannot render the card. - `AppClipPartResponse object { reactions, type, value, 3 more }` An App Clip card part - `reactions: array of Reaction` 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. - `id: optional string` Identifier for this reaction. Pass it to `PATCH /v3/messages/{messageId}/reactions/{reactionId}` to move a sticker. Stickers placed before this API shipped can be read but not moved: the device-side reference needed to reposition them was never recorded, so `PATCH` returns 404 for those. - `custom_emoji: optional string` Custom emoji if type is "custom", null otherwise - `sticker: optional object { file_name, height, mime_type, 2 more }` Sticker attachment details when reaction_type is "sticker". Null for non-sticker reactions. - `type: "app_clip"` Indicates this is an App Clip card part - `"app_clip"` - `value: string` The App Clip link the card opens - `description: optional string` The card's summary line, composed by Linq from the App Clip page - `image_url: optional string` The card's preview image - `title: optional string` The card's headline, composed by Linq from the App Clip page - `sent_at: string` When the message was actually sent (null if still queued) - `delivered_at: optional string` When the message was delivered - `effect: optional MessageEffect` iMessage effect applied to a message (screen or bubble effect) - `name: optional 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: optional "screen" or "bubble"` Type of effect - `"screen"` - `"bubble"` - `from_handle: optional ChatHandle` The sender of this message as a full handle object - `preferred_service: optional ServiceType` Messaging service type - `reply_to: optional ReplyTo` Indicates this message is a threaded reply to another message - `message_id: string` The ID of the message to reply to - `part_index: optional 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: optional ServiceType` Messaging service type ### Example ```http curl https://api.linqapp.com/api/partner/v3/chats/$CHAT_ID/messages \ -H 'Content-Type: application/json' \ -H "Authorization: Bearer $LINQ_API_V3_API_KEY" \ -d '{ "message": { "parts": [ { "type": "text", "value": "Hello, world!" } ] } }' ``` #### Response ```json { "chat_id": "550e8400-e29b-41d4-a716-446655440000", "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", "id": "9f8b1c2d-3e4f-5061-7283-94a5b6c7d8e9", "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!", "mention": "+14155551234", "mention_range": [ 4, 9 ], "mentions": [ { "handle": "+14155550123", "is_me": true, "range": [ 4, 9 ] } ], "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" } } ```