Slack

Slack Chat API

The Chat API from Slack — 10 operation(s) for chat.

GitHub OpenAPI

Operations 10

Each operation below carries the questions people ask an LLM about it and the instructions they give an agent to run it. Generated by API Evangelist overlay

POST /chat.delete Delete a posted message · Slack Post Chat Delete #
Ask an LLM
“How do I delete a message my bot already posted?”
“Can I delete a message as the user rather than as the bot?”
Tell an agent destructive · confirm first
Delete message {ts} in channel {channel}.
Remove the already-posted message at {ts} from {channel}.
POST /chat.deleteScheduledMessage Cancel a scheduled message · Slack Post Chat Deletescheduledmessage #
Ask an LLM
“Can I cancel a message I scheduled before it gets sent?”
“What do I need to remove a pending scheduled message from the queue?”
Tell an agent destructive · confirm first
Cancel scheduled message {scheduled_message_id} in {channel}.
Remove pending scheduled message {scheduled_message_id} from channel {channel} before it goes out.
POST /chat.meMessage Post a /me status-style message · Slack Post Chat Memessage #
Ask an LLM
“Can I post an italic /me style action message in a channel?”
“What is a me message and when would I send one?”
Tell an agent
Post a /me message saying {text} in {channel}.
Share a me action {text} into channel {channel}.
POST /chat.postEphemeral Send a message only one user can see · Slack Post Chat Postephemeral #
Ask an LLM
“How do I send a message in a channel that only one person can see?”
“Can an ephemeral message be posted inside a thread?”
Tell an agent
Send {user} an ephemeral message in {channel} saying {text}.
Show only {user} the private notice {text} in thread {thread_ts} of {channel}.
POST /chat.postMessage Send a message to a channel · Slack Post Chat Postmessage #
Ask an LLM
“How do I post a message to a Slack channel from my app?”
“Can I reply in a thread and also broadcast the reply to the channel?”
Tell an agent
Post {text} to channel {channel}.
Reply {text} in thread {thread_ts} of {channel}.
POST /chat.scheduleMessage Schedule a message for later · Slack Post Chat Schedulemessage #
Ask an LLM
“Can I schedule a message to post at a specific time in the future?”
“Which formats, like blocks or thread replies, work with scheduled messages?”
Tell an agent
Schedule {text} to post in {channel} at {post_at}.
Schedule a thread reply {text} to {thread_ts} in {channel} for {post_at}.
GET /chat.scheduledMessages.list List scheduled messages · Slack Get Chat Scheduledmessages List #
Ask an LLM
“What messages are currently scheduled to go out?”
“Can I see scheduled messages for just one channel within a time range?”
Tell an agent
List all my pending scheduled messages.
List scheduled messages in {channel} due between {oldest} and {latest}.
POST /chat.unfurl Provide custom link previews for posted URLs · Slack Post Chat Unfurl #
Ask an LLM
“How do I show a custom preview when someone posts a link to my app's domain?”
“Can I ask users to authenticate before my app unfurls their link?”
Tell an agent
Unfurl the links in message {ts} of {channel} with previews {unfurls}.
Prompt the user to sign in at {user_auth_url} before unfurling message {ts} in {channel}.
POST /chat.update Edit a message that was already posted · Slack Post Chat Update #
Ask an LLM
“Can I edit the text of a message after it has been posted?”
“Is it possible to swap an existing message's blocks for new ones?”
Tell an agent
Change message {ts} in {channel} to say {text}.
Replace the blocks of existing message {ts} in {channel} with {blocks}.

Documentation

📖
Documentation
https://docs.slack.dev/admins
📖
Documentation
https://docs.slack.dev/reference/methods
📖
Documentation
https://docs.slack.dev/authentication
📖
Documentation
https://docs.slack.dev/surfaces/canvases
📖
Documentation
https://docs.slack.dev/apis/web-api/using-the-conversations-api
📖
Documentation
https://docs.slack.dev/workflows/workflow-steps
📖
Documentation
https://docs.slack.dev/surfaces/lists
📖
Documentation
https://docs.slack.dev/authentication/sign-in-with-slack
📖
Documentation
https://docs.slack.dev/legacy/legacy-rtm-api
📖
Documentation
https://docs.slack.dev/workflows
📖
Documentation
https://docs.slack.dev/apis/web-api
📖
APIReference
https://docs.slack.dev/reference/methods
📖
RateLimits
https://docs.slack.dev/apis/web-api/rate-limits

Specifications

⚙
OpenAPI
https://raw.githubusercontent.com/api-evangelist/slack/refs/heads/main/openapi/slack-chat-api-openapi.yml

Schemas & Data

📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/slack/refs/heads/main/json-schema/slack-message-schema.json
📊
JSONSchema
https://raw.githubusercontent.com/api-evangelist/slack/refs/heads/main/json-schema/slack-channel-schema.json

Other Resources

🔗
JSONLD
https://raw.githubusercontent.com/api-evangelist/slack/refs/heads/main/json-ld/slack-context.jsonld

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OpenAPI Specification

slack-chat-api-openapi.yml Raw ↑ 
openapi: 3.2.0
info:
  title: Slack Chat API
  version: '1.0'
  description: 'Operations tagged Chat across 2 of this provider''s published API definitions: slack-chat-openapi.yml, slack-web-api-openapi.yml. Each path carries the servers of the definition it was published in.'
servers:
- url: https://slack.com/api
  description: Slack Web API production server
tags:


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# Full source: https://raw.githubusercontent.com/api-evangelist/slack/refs/heads/main/openapi/slack-chat-api-openapi.yml