reactions.add

Adds a reaction to an item.

Facts

Method URL:https://slack.com/api/reactions.add
Preferred HTTP method:POST
Accepted content types:application/x-www-form-urlencoded, application/json
Rate limiting:Tier 3
Works with:
Token typeRequired scope(s)
botreactions:write 
userreactions:write 

This method adds a reaction (emoji) to a message. Now that file threads work the way you'd expect, the file and file_comment arguments are deprecated. Specify only channel and timestamp instead.

Arguments

Argument Example Required Description
tokenxxxx-xxxxxxxxx-xxxxRequired

Authentication token bearing required scopes.

channelC1234567890Required

Channel where the message to add reaction to was posted.

namethumbsupRequired

Reaction (emoji) name.

timestamp1234567890.123456Required

Timestamp of the message to add reaction to.

This method supports application/json via HTTP POST. Present your token in your request's Authorization header. Learn more.

Response

Typical success response

{
    "ok": true
}

Typical error response

{
    "error": "already_reacted",
    "ok": false
}

After making this call, the reaction is saved and a reaction_added event is broadcast via the Events and RTM APIs.

A not_reactable error is thrown when we decline the opportunity to attach your app's personally selected emoji reaction to a file or file comment. It's not because of how your app feels, it's because that approach is retired. Your app can express its inner reacji for any message though, by specifying channel and timestamp.

Errors

This table lists the expected errors that this method could return. However, other errors can be returned in the case where the service is down or other unexpected factors affect processing. Callers should always check the value of the ok params in the response.

ErrorDescription
not_reactable

Whatever you passed in, like a file or file_comment, can't be reacted to anymore. Your app can react to messages though.

invalid_name

Value passed for name was invalid.

too_many_emoji

The limit for distinct reactions (i.e emoji) on the item has been reached.

message_not_found

Message specified by channel and timestamp does not exist.

already_reacted

The specified item already has the user/reaction combination.

bad_timestamp

Value passed for timestamp was invalid.

too_many_reactions

The limit for reactions a person may add to the item has been reached.

no_item_specified

combination of channel and timestamp was not specified.

is_archived

Channel specified has been archived.

channel_not_found

Value passed for channel is invalid.

not_authed

No authentication token provided.

invalid_auth

Some aspect of authentication cannot be validated. Either the provided token is invalid or the request originates from an IP address disallowed from making the request.

account_inactive

Authentication token is for a deleted user or workspace.

token_revoked

Authentication token is for a deleted user or workspace or the app has been removed.

no_permission

The workspace token used in this request does not have the permissions necessary to complete the request. Make sure your app is a member of the conversation it's attempting to post a message to.

org_login_required

The workspace is undergoing an enterprise migration and will not be available until migration is complete.

ekm_access_denied

Administrators have suspended the ability to post a message.

missing_scope

The token used is not granted the specific scope permissions required to complete this request.

invalid_arguments

The method was called with invalid arguments.

invalid_arg_name

The method was passed an argument whose name falls outside the bounds of accepted or expected values. This includes very long names and names with non-alphanumeric characters other than _. If you get this error, it is typically an indication that you have made a very malformed API call.

invalid_charset

The method was called via a POST request, but the charset specified in the Content-Type header was invalid. Valid charset names are: utf-8 iso-8859-1.

invalid_form_data

The method was called via a POST request with Content-Type application/x-www-form-urlencoded or multipart/form-data, but the form data was either missing or syntactically invalid.

invalid_post_type

The method was called via a POST request, but the specified Content-Type was invalid. Valid types are: application/json application/x-www-form-urlencoded multipart/form-data text/plain.

missing_post_type

The method was called via a POST request and included a data payload, but the request did not include a Content-Type header.

team_added_to_org

The workspace associated with your request is currently undergoing migration to an Enterprise Organization. Web API and other platform operations will be intermittently unavailable until the transition is complete.

request_timeout

The method was called via a POST request, but the POST data was either missing or truncated.

fatal_error

The server could not complete your operation(s) without encountering a catastrophic error. It's possible some aspect of the operation succeeded before the error was raised.

Warnings

This table lists the expected warnings that this method will return. However, other warnings can be returned in the case where the service is experiencing unexpected trouble.

WarningDescription
missing_charset

The method was called via a POST request, and recommended practice for the specified Content-Type is to include a charset parameter. However, no charset was present. Specifically, non-form-data content types (e.g. text/plain) are the ones for which charset is recommended.

superfluous_charset

The method was called via a POST request, and the specified Content-Type is not defined to understand the charset parameter. However, charset was in fact present. Specifically, form-data content types (e.g. multipart/form-data) are the ones for which charset is superfluous.