Reactions

React to any message with built-in iMessage tapbacks or custom Unicode emoji. Reactions are an iMessage feature — see Protocol Selection for protocol capabilities. See the Reactions API Reference for the full endpoint specification.

Adding a reaction

curl -X POST https://api.linqapp.com/api/partner/v3/messages/{message_id}/reactions \
  -H "Authorization: Bearer $LINQ_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "love",
    "operation": "add"
  }'

await client.messages.addReaction(messageId, {
  type: 'love',
  operation: 'add',
});

client.messages.add_reaction(
    message_id,
    type="love",
    operation="add",
)

Built-in reaction types

These map to the standard iMessage tapback reactions:

Type	Description
love	Heart
like	Thumbs up
dislike	Thumbs down
laugh	Ha ha
emphasize	Exclamation marks
question	Question mark

Custom emoji reactions

Send any Unicode emoji as a reaction:

curl -X POST https://api.linqapp.com/api/partner/v3/messages/{message_id}/reactions \
  -H "Authorization: Bearer $LINQ_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "type": "custom",
    "custom_emoji": "🎉",
    "operation": "add"
  }'

Targeting multipart messages

For messages with multiple parts, target a specific part using part_index (0-based):

{
  "type": "love",
  "operation": "add",
  "part_index": 1
}

This reacts to the second part of the message. If omitted, the reaction applies to the first part.

Removing reactions

Use the same endpoint with "operation": "remove" and the matching type you originally added.

Sticker attachments

A contact can attach a sticker to any message part in iMessage. This is distinct from a custom sticker reaction — the type is "sticker" and the payload includes image metadata.

Sticker attachments are inbound only; the API does not support sending them.

They appear inside parts[].reactions[] on the message and trigger a reaction.added event:

{
  "parts": [
    {
      "type": "text",
      "value": "Hey yea",
      "reactions": [
        {
          "type": "sticker",
          "is_me": false,
          "custom_emoji": null,
          "sticker": {
            "file_name": "sticker-abc123.png",
            "mime_type": "image/png",
            "url": "https://cdn.linqapp.com/attachments/550e8400/sticker-abc123.png",
            "width": 320,
            "height": 320
          },
          "handle": {
            "id": "550e8400-e29b-41d4-a716-446655440011",
            "handle": "+14155559876",
            "is_me": false,
            "service": "iMessage",
            "status": "active",
            "joined_at": "2025-11-23T17:30:00.000Z",
            "left_at": null
          }
        }
      ]
    }
  ]
}

Reaction webhook events

Event	Description
reaction.added	A reaction was added to a message
reaction.removed	A reaction was removed from a message

Webhook payloads include reaction_type, message_id, part_index, and sender information. See Reaction events for full payload details.