Slack

Connect to Slack workspaces to use communication features such as sending messages, managing channels, and retrieving user information.

Key Features

• Channel list retrieval
• Message sending and thread replies
• Emoji reaction addition
• Channel history retrieval
• User information retrieval
• Thread reply retrieval

Basic Information

Authentication Method

Authenticates using OAuth 2.0.

Required Permissions

• channels:history: Read channel history
• chat:write: Write messages
• identify: User identity verification
• reactions:read: Read reactions
• reactions:write: Add reactions
• search:read: Search functionality
• users:read: Read user information
• users.profile:read: Read user profiles
• channels:read: Read channel information

Supported MCP Tools

Channel Management Tools

list_channels

Retrieves the list of public channels in the workspace with pagination.

Input Parameters:

• limit (optional): Number of channels to retrieve at once (default: 100)
• cursor (optional): Pagination cursor
• includeArchived (optional): Whether to include archived channels

get_channel_history

Retrieves recent messages from a channel.

Input Parameters:

• channelId (required): Channel ID
• limit (optional): Number of messages to retrieve

Message Management Tools

post_message

Sends a new message to a Slack channel.

Input Parameters:

• channelId (required): Channel ID to send the message to
• text (required): Message content

reply_to_thread

Creates a reply to a specific message thread.

Input Parameters:

• channelId (required): Channel ID
• threadTs (required): Thread timestamp
• text (required): Reply content

get_thread_replies

Retrieves all replies in a message thread.

Input Parameters:

• channelId (required): Channel ID
• threadTs (required): Thread timestamp

Reaction Management Tools

add_reaction

Adds an emoji reaction to a message.

Input Parameters:

• channelId (required): Channel ID
• timestamp (required): Message timestamp
• reaction (required): Reaction emoji name

User Management Tools

get_users

Retrieves the list of all users in the workspace and their basic profile information.

Input Parameters:

• limit (optional): Number of users to retrieve
• cursor (optional): Pagination cursor

get_user_profile

Retrieves detailed profile information for a specific user.

Input Parameters:

• userId (required): User ID

Usage Example

For example,

• When you input “Send a ‘Hello’ message to the #general channel in Slack” as a prompt,
• The LLM calls the post_message tool through MCP to send the message.
• Then, it responds in the chat based on the tool call results.