# Slack MCP Server
MCP server for Slack API integration with HTTP transport.
## Authentication Methods
### Option 1: Bot/User Token (Recommended)
Standard Slack API tokens. Requires a Slack app with appropriate scopes.
```bash
export SLACK_TOKEN=xoxb-your-bot-token
# or
export SLACK_TOKEN=xoxp-your-user-token
```
### Option 2: Cookie-Based Auth (User Impersonation)
Uses browser session cookies to impersonate a logged-in user. Useful when:
- You don't have admin approval for a Slack app
- You need to act as a specific user
- You want to access private channels the user is a member of
#### Extracting Tokens from Chrome
1. **Open Chrome DevTools** on your Slack workspace:
- Navigate to `https://your-workspace.slack.com`
- Press `F12` or right-click → "Inspect"
- Go to the **Application** tab
2. **Get the `xoxc` token:**
- In DevTools, go to **Console** tab
- Paste and run:
```javascript
JSON.parse(localStorage.localConfig_v2).teams[Object.keys(JSON.parse(localStorage.localConfig_v2).teams)[0]].token
```
- Copy the `xoxc-...` token
3. **Get the `xoxd` cookie:**
- In DevTools, go to **Application** → **Cookies** → `https://your-workspace.slack.com`
- Find the cookie named `d`
- Copy the **Value** (starts with `xoxd-...`)
- ⚠️ The value is URL-encoded — keep it as-is
4. **Get workspace details:**
- **Team ID**: In Console, run:
```javascript
JSON.parse(localStorage.localConfig_v2).teams[Object.keys(JSON.parse(localStorage.localConfig_v2).teams)[0]].id
```
- **User ID**: Run:
```javascript
JSON.parse(localStorage.localConfig_v2).teams[Object.keys(JSON.parse(localStorage.localConfig_v2).teams)[0]].user_id
```
- **Domain**: Your Slack URL (e.g., `your-workspace.slack.com`)
5. **Create your env file:**
```bash
cp cookie-tokens.env.example /path/to/secrets/cookie-tokens.env
# Edit the file with your extracted values
```
#### Using the Cookie Client
A shell script is provided for quick API calls:
```bash
# Set up your tokens
source /path/to/secrets/cookie-tokens.env
# Test authentication
./scripts/slack-cookie-client.sh auth
# List channels
./scripts/slack-cookie-client.sh channels 20
# Get channel history
./scripts/slack-cookie-client.sh history C0123ABCDEF 10
# Send a message
./scripts/slack-cookie-client.sh send C0123ABCDEF "Hello from the script!"
# Search messages
./scripts/slack-cookie-client.sh search "keyword"
# List users
./scripts/slack-cookie-client.sh users 50
```
#### Token Expiration
Cookie tokens expire when:
- You log out of Slack in the browser
- You change your password
- Slack rotates session tokens (typically every few weeks)
When tokens expire, repeat the extraction process.
---
## Setup (Standard Token)
1. Get a Slack token (Bot Token `xoxb-...` or User Token `xoxp-...`)
2. Configure environment:
```bash
export SLACK_TOKEN=xoxb-your-token
```
3. Run:
```bash
npm install
npm run start:http
```
## Docker
```bash
docker build -t slack-mcp .
docker run -d -p 3929:3929 -e SLACK_TOKEN=xoxb-... slack-mcp
```
## Endpoints
- `GET /health` - Health check
- `GET /tools` - List available tools
- `POST /call` - Call a tool
## Available Tools
| Tool | Description |
|------|-------------|
| `slack_list_channels` | List channels |
| `slack_get_channel_history` | Get channel messages |
| `slack_post_message` | Send a message |
| `slack_update_message` | Edit a message |
| `slack_delete_message` | Delete a message |
| `slack_add_reaction` | Add emoji reaction |
| `slack_get_user_info` | Get user details |
| `slack_list_users` | List workspace users |
| `slack_search_messages` | Search messages |
## Example
```bash
# List channels
curl -X POST http://localhost:3929/call \
-H "Content-Type: application/json" \
-d '{"name": "slack_list_channels", "arguments": {}}'
# Post message
curl -X POST http://localhost:3929/call \
-H "Content-Type: application/json" \
-d '{"name": "slack_post_message", "arguments": {"channel": "C123", "text": "Hello!"}}'
```
## Token Scopes Required
For Bot Token (`xoxb-...`):
- `channels:read`, `channels:history`
- `chat:write`
- `users:read`
- `reactions:write`
- `search:read` (for search)
For User Token (`xoxp-...`):
- Same as above, plus any additional scopes for your use case
For Cookie Auth:
- No scopes needed — inherits all permissions of the logged-in user
