---
title: "Add reaction"
method: POST
path: "/v1/inbox/conversations/{conversationId}/messages/{messageId}/reactions"
tags: ["Messages"]
---

# Add reaction

`POST /v1/inbox/conversations/{conversationId}/messages/{messageId}/reactions`

Add an emoji reaction to a message. Platform support:
- Telegram: Supports a subset of Unicode emoji reactions
- WhatsApp: Supports any standard emoji (one reaction per message per sender)
- Instagram and Facebook Messenger: Any standard emoji, subject to Meta's 24h messaging window
- Slack: The emoji must have a Slack name (e.g. `:thumbsup:`); unnamed characters return 400
- All others: Returns 400 (not supported)

## Path parameters

- `conversationId` string, required
- `messageId` string, required

## Request body

- object
  - `accountId` string, required — Social account ID
  - `emoji` string, required — Emoji character (e.g. "👍", "❤️")

## Response `200`

Reaction added

- object
  - `success` boolean

## Other responses

- `400` — Platform does not support reactions or invalid request
- `401` — Unauthorized
- `403` — Inbox addon required
- `404` — Account or conversation not found

---

[API](https://skmtc.net/zernio/apis/zernio-api.md) · [All operations](https://skmtc.net/zernio/apis/zernio-api/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/zernio/zernio-api/revisions/f81ca70ea6b9/schema)