Slack MCP Server
Give your AI agents full Slack access — messages, threads, DMs, channels, canvases, reactions, and search. 27 tools over the Slack Web API with enterprise governance and audit-ready risk classification.
Architecture
Tools (27)
Comparison with Other Slack MCP Servers
Installation
Build from source
git clone https://github.com/zavora-ai/mcp-slack
cd mcp-slack
cargo build --release
From crates.io
cargo install mcp-slack
Configuration
Environment Variables
Required Bot Token Scopes
channels:read — list channels
channels:history — read messages
channels:manage — set topic
groups:read — private channels
groups:history — private channel messages
chat:write — send messages
reactions:write — add reactions
search:read — search messages
users:read — list/get users
files:write — upload files
channels:join — self-join channels (optional)
Slack App Manifest
display_information:
name: MCP Slack Bot
description: AI agent access to Slack via MCP protocol
features:
bot_user:
display_name: MCP Bot
always_online: true
oauth_config:
scopes:
bot:
- channels:read
- channels:history
- channels:manage
- groups:read
- groups:history
- chat:write
- reactions:write
- search:read
- users:read
- files:write
settings:
org_deploy_enabled: false
socket_mode_enabled: false
token_rotation_enabled: false
Client Configuration
Claude Desktop
{
"mcpServers": {
"slack": {
"command": "mcp-slack",
"args": [],
"env": {
"SLACK_BOT_TOKEN": "xoxb-your-token"
}
}
}
}
Kiro
Add to .kiro/settings/mcp.json:
{
"mcpServers": {
"slack": {
"command": "mcp-slack",
"args": [],
"env": {
"SLACK_BOT_TOKEN": "xoxb-your-token"
}
}
}
}
Cursor
Add to .cursor/mcp.json:
{
"mcpServers": {
"slack": {
"command": "mcp-slack",
"args": [],
"env": {
"SLACK_BOT_TOKEN": "xoxb-your-token"
}
}
}
}
Codex (OpenAI)
{
"mcpServers": {
"slack": {
"command": "mcp-slack"
}
}
}
Windsurf
Add to ~/.codeium/windsurf/mcp_config.json:
{
"mcpServers": {
"slack": {
"command": "mcp-slack",
"args": [],
"env": {
"SLACK_BOT_TOKEN": "xoxb-your-token"
}
}
}
}
Quick Start
# Set token
export SLACK_BOT_TOKEN="xoxb-your-token"
# Verify token works
curl -s -H "Authorization: Bearer $SLACK_BOT_TOKEN" https://slack.com/api/auth.test
# Run server
mcp-slack
Test with MCP Inspector
npx @modelcontextprotocol/inspector mcp-slack
Usage Examples
List channels
"List my Slack channels"
→ calls list_channels
Read a thread
"What did the team say in the thread about the deployment?"
→ calls search_messages → get_thread
Send a message
"Post in #engineering: the release is ready for QA"
→ calls send_message with channel + text
Reply in a thread
"Reply to that message saying I'll review it"
→ calls send_message with thread_ts
Open a DM
"Send a DM to James asking about the PR"
→ calls open_dm → send_message
Create a channel
"Create a private channel called project-alpha"
→ calls create_channel with is_private=true
MCP Server Manifest
server_id = "mcp_slack"
display_name = "Slack"
version = "1.3.0"
domain = "collaboration"
risk_level = "medium"
writes_allowed = "gated"
transports = ["stdio"]
credentials = ["vault://slack-bot-token"]
Testing
# Build
cargo build
# Run tests
cargo test
# Integration test (requires SLACK_BOT_TOKEN)
echo '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2024-11-05","capabilities":{},"clientInfo":{"name":"test","version":"1.0"}}}
{"jsonrpc":"2.0","id":2,"method":"tools/call","params":{"name":"list_channels","arguments":{"limit":5}}}' | cargo run
Roadmap
- OAuth user token support (for user-level access beyond bot)
- Workflow triggers (
workflows.triggers.create) - Pin messages (
pins.add,pins.list) - User presence/status (
users.setPresence,users.profile.set)
Registry Compliance
This server implements the ADK MCP SDK contract:
- HealthCheck — async health probe for registry monitoring
- mcp-server.toml — manifest declaring tools, risk classes, and credentials
- Structured tracing —
RUST_LOGenv-filter for observability
Contributors
License
Apache-2.0 — see LICENSE for details.
Part of the ADK-Rust Enterprise MCP server ecosystem.
Built with ❤️ by Zavora AI
rmcp and MCP compatibility
This server is built with rmcp 3.1.2 and requires Rust 1.94.1 or newer. The rmcp 3 rollout retains legacy MCP initialization compatibility and targets MCP protocol revisions 2025-11-25 and 2026-07-28.
MCP 2026-07-28 rollout (P4 workflow/business)
This server uses rmcp 3.1.2 and adk-mcp-sdk 0.2 with a minimum supported
Rust version of 1.94.1. It accepts stateless MCP 2026 requests with
per-request protocol, client identity, and capability metadata while retaining
the legacy MCP 2025-11-25 initialize flow for ordinary tools.
- Tasks:
upload_file - MRTR approvals:
send_message,upload_file - Discovery and routing: rmcp serves on-demand discovery and validates the
per-request protocol envelope; HTTP deployments can route with
Mcp-MethodandMcp-Name. The packaged binary currently uses stdio. - Caching:
tools/listreturns a publicttlMsof 60,000 for MCP 2026; rmcp omits the cache fields for legacy clients. - Deprecated extensions: this server does not add new Roots, Sampling, or dynamic client-registration dependencies.
Protected tools require MCP_REQUEST_STATE_KEY with at least 32 high-entropy
bytes. All replicas must share that key so sealed approval state can resume on
another instance. Approval state is bound to the client identity, tool, and
arguments and expires after two minutes. Missing identity, invalid state,
rejection, or legacy protocol use fails closed. Task records are process-local
for the current stdio runtime; use a durable task store before deploying the
server behind scale-to-zero HTTP infrastructure.