Slack MCP Server (Ubie, Inc.)
Slack workspaces accessible for AI to list channels, search history, and post messages.
Data last scanned today · Reviewed today
Overview
This MCP server provides a standardized interface for AI assistants to interact with the Slack API. It supports both Stdio and Streamable HTTP transport methods, enabling deployment in local environments or remote configurations via configurable ports. Developers can leverage a comprehensive suite of tools for workspace management, including channel browsing, message posting, threading, and emoji reactions. The server also includes an advanced message search capability with filters for users, dates, and content, alongside batch retrieval tools for user profile information.
Our verdict
With a security score of 43/100, this server is currently classified as high-risk. The score reflects that the project is community-maintained rather than official and lacks an independent editorial review of its authentication and OAuth handling. Given that critical security components like OAuth support remain unreviewed, this server is recommended for testing environments rather than production use in sensitive workspaces.
- Supports both Stdio and Streamable HTTP transport methods.
- Includes a granular SLACK_SAFE_SEARCH mode for privacy.
- Features advanced search filters for message retrieval.
- Small footprint with only eight direct dependencies.
- Community-maintained project with no official vendor backing.
- OAuth support and read-only modes lack independent review.
- Requires high-privilege tokens for full search functionality.
Setup
{
"mcpServers": {
"ubie-oss-slack-mcp-server": {
"args": [
"-y",
"@ubie-oss/slack-mcp-server"
],
"command": "npx"
}
}
}Paste into ~/Library/Application Support/Claude/claude_desktop_config.json (macOS) or %APPDATA%\Claude\claude_desktop_config.json (Windows), then restart Claude Desktop. Some servers require API keys or tokens as environment variables — check the project's README and add an "env" object if needed.
- No read-only mode — running this grants full read/write access.
- No built-in authentication — anyone with access to this config can invoke every tool it exposes.
Tools
| Tool | Description | Risk |
|---|---|---|
| slack_list_channels | List public channels in the workspace with pagination | low |
| slack_post_message | Post a new message to a Slack channel | medium |
| slack_reply_to_thread | Reply to a specific message thread in Slack | medium |
| slack_add_reaction | Add a reaction emoji to a message | medium |
| slack_get_channel_history | Get recent messages from a channel | low |
| slack_get_thread_replies | Get all replies in a message thread | low |
| slack_get_users | Retrieve basic profile information of all users in the workspace | low |
| slack_get_user_profiles | Get multiple users' profile information in bulk (efficient for batch operations) | low |
| slack_search_messages | Search for messages in the workspace with powerful filters | low |
Compatibility
| Client | Local | Docker | Remote | Read-only |
|---|---|---|---|---|
| Claude Desktop | ||||
| Cursor | ||||
| VS Code | ||||
| Windsurf | ||||
| ChatGPT |
Frequently asked questions
›What authentication tokens are required to run this server?
You must provide a SLACK_BOT_TOKEN for basic functionality and a SLACK_USER_TOKEN, which is required for specific features like message search.
›How can I limit the scope of search results to exclude private channels or DMs?
You can set the SLACK_SAFE_SEARCH environment variable to true, which enforces the exclusion of private channels, DMs, and group DMs from search results.
›What transport methods does the Slack MCP server support?
The server supports Stdio transport for local process-based communication and Streamable HTTP transport for remote or web-based applications.
›Are there special requirements for installing the package?
The package is hosted in the GitHub Registry, so you need to provide a GitHub Personal Access Token (PAT) to install it via npm.
›Can I run the server on a specific port for HTTP communication?
Yes, you can specify a port using the -port command line option when starting the server.
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