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chat.scheduleMessage

Facts

Method URL:https://slack.com/api/chat.scheduleMessage
Preferred HTTP method:POST
Accepted content types:application/x-www-form-urlencoded, application/json
Rate limiting:Tier 3
Works with:
Token typeRequired scope(s)
botbot
userchat:write:user  chat:write:bot 

This method schedules a message for delivery to a public channel, private channel, or direct message/IM channel at a specified time in the future.

Arguments

Argument Example Required Description
tokenxxxx-xxxxxxxxx-xxxxRequired

Authentication token bearing required scopes.

channelC1234567890Required

Channel, private group, or DM channel to send message to. Can be an encoded ID, or a name. See below for more details.

post_at299876400Required

Unix EPOCH timestamp of time in future to send the message.

textHello worldRequired

Text of the message to send. See below for an explanation of formatting. This field is usually required, unless you're providing only attachments instead. Provide no more than 40,000 characters or risk truncation.

as_usertrueOptional

Pass true to post the message as the authed user, instead of as a bot. Defaults to false. See authorship below.

attachments[{"pretext": "pre-hello", "text": "text-world"}]Optional

A JSON-based array of structured attachments, presented as a URL-encoded string.

blocks[{"type": "section", "text": {"type": "plain_text", "text": "Hello world"}}]Optional

A JSON-based array of structured blocks, presented as a URL-encoded string.

link_namestrueOptional

Find and link channel names and usernames.

parsefullOptional

Change how messages are treated. Defaults to none. See below.

reply_broadcasttrueOptional

Used in conjunction with thread_ts and indicates whether reply should be made visible to everyone in the channel or conversation. Defaults to false.

thread_ts1234567890.123456Optional

Provide another message's ts value to make this message a reply. Avoid using a reply's ts value; use its parent instead.

unfurl_linkstrueOptional

Pass true to enable unfurling of primarily text-based content.

unfurl_mediafalseOptional

Pass false to disable unfurling of media content.

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

The post_at arg is a Unix EPOCH timestamp, representing the time the message should post to Slack in the future.

With the exception of the additional post_at argument, this method behaves identically to chat.postMessage. Peruse that page for in-depth documentation on each parameter that this method accepts.

A message must have either text or attachments or both. The text parameter is required unless you provide attachments. You can use both parameters in conjunction with each other to create awesome messages.

Restrictions

You will only be able to schedule a message up to 120 days into the future. If you specify a post_at timestamp beyond this limit, you’ll receive a time_too_far error response.

Response

Typical success response

{
    "ok": true,
    "channel": "C1H9RESGL",
    "scheduled_message_id": "Q1298393284",
    "post_at": "1562180400",
    "message": {
        "text": "Here's a message for you in the future",
        "username": "ecto1",
        "bot_id": "B19LU7CSY",
        "attachments": [
            {
                "text": "This is an attachment",
                "id": 1,
                "fallback": "This is an attachment's fallback"
            }
        ],
        "type": "delayed_message",
        "subtype": "bot_message"
    }
}

Typical error response if the post_at is invalid (ex. in the past or too far into the future)

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

The response includes the scheduled_message_id assigned to your message. Use it with the chat.deleteScheduledMessage method to delete the message before it is sent.

For details on formatting, usage in threads, and rate limiting, check out chat.postMessage documentation.

Channels

You must specify a public channel, private channel, or an IM channel with the channel argument. Each one behaves slightly differently based on the authenticated user's permissions and additional arguments:

Post to a channel

You can either pass the channel's name (#general) or encoded ID (C024BE91L), and the message will be posted to that channel. The channel's ID can be retrieved through the channels.list API method.

Post to a DM

Pass the IM channel's ID (D023BB3L2) or a user's ID (U0G9QF9C6) as the value of channel to post to that IM channel as the app. The IM channel's ID can be retrieved through the im.list API method.

You might receive a channel_not_found error if your app doesn't have permission to enter into an IM with the intended user.

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
invalid_time

value passed for post_time was invalid.

time_in_past

value passed for post_time was in the past.

time_too_far

value passed for post_time was too far into the future.

channel_not_found

Value passed for channel was invalid.

not_in_channel

Cannot post user messages to a channel they are not in.

is_archived

Channel has been archived.

msg_too_long

Message text is too long

no_text

No message text provided

restricted_action

A workspace preference prevents the authenticated user from posting.

restricted_action_read_only_channel

Cannot post any message into a read-only channel.

restricted_action_thread_only_channel

Cannot post top-level messages into a thread-only channel.

restricted_action_non_threadable_channel

Cannot post thread replies into a non_threadable channel.

too_many_attachments

Too many attachments were provided with this message. A maximum of 100 attachments are allowed on a message.

rate_limited

Application has posted too many messages, read the Rate Limit documentation for more information

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
message_truncated

The text field of a message should have no more than 40,000 characters. We truncate really long messages.

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.