send_slack_notification
Sends a notification to a Slack channel with a title and description
LABSCO SUMMARY
The "it's done" message, sent by the thing that finished.
One tool doing one job: an agent that has been running a long task tells the channel itself, with the people who were waiting already mentioned.
What it is
A single-tool notification server for Slack, using an OAuth bot token. A message goes to a channel with a title and a description, formatted with Slack's markdown and an optional header.
What you get
- A formatted message posted to a Slack channel with a title and a description
- Specific users mentioned by passing them on the call, or by default on every message
- Slack markdown formatting supported in the body
- A default channel configured, so routine notifications do not need one named each time
Requirements
npx @mkusaka/mcp-server-slack-notify@latest. A Slack app with the chat:write bot scope installed to your workspace; its bot token, which starts with xoxb-, goes in SLACK_BOT_TOKEN. SLACK_DEFAULT_CHANNEL and SLACK_MENTIONS are optional. The bot has to be invited to any channel it posts in.
Setup effort
One command plus a key — claude mcp add slack-notify -e SLACK_BOT_TOKEN=<YOUR_SLACK_BOT_TOKEN> -e SLACK_DEFAULT_CHANNEL=#general -e SLACK_MENTIONS=U1234567890,U0987654321 -- npx -y @mkusaka/mcp-server-slack-notify@latest
USE CASES
01
Being told when a long job finishes
The agent posts the result to the channel itself, so you can leave the terminal.
02
Pulling the right person in
Mention the people who need to see it on the call itself, rather than posting and then tagging.
03
Reporting a failure where the team will see it
A title and a description in the same message means the channel gets the headline and the detail together.
1 tool
Counted once with only startup setup. Other versions, modes or optional credentials may expose a different list.
BEFORE YOU INSTALL
What to know first
Tools you get
1 tool when we connected. It only posts and cannot read Slack. SLACK_MENTIONS adds the same mentions to every message, which is easy to forget once set.
Requires
- npx on PATH
- SLACK_BOT_TOKEN in your environment
Where it runs
All 4 documented setups run the server on your machine.
CONTEXT COST
Light Standing cost
Rated by the size of the one tool definition that rides along on every turn
INSTALLATION
Connect your client
Server setup
Claude Code
TERMINAL
claude mcp add slack-notify -e SLACK_BOT_TOKEN=<YOUR_SLACK_BOT_TOKEN> -e SLACK_DEFAULT_CHANNEL=#general -e SLACK_MENTIONS=U1234567890,U0987654321 -- npx -y @mkusaka/mcp-server-slack-notify@latestMCP Clients
Claude Desktop
CLAUDE DESKTOP · JSON
{
"mcpServers": {
"slack-notify": {
"command": "npx",
"args": [
"-y",
"@mkusaka/mcp-server-slack-notify@latest"
],
"env": {
"SLACK_BOT_TOKEN": "<YOUR_SLACK_BOT_TOKEN>",
"SLACK_DEFAULT_CHANNEL": "#general",
"SLACK_MENTIONS": "U1234567890,U0987654321"
}
}
}
}Claude Code — user scope
CLAUDE CODE — USER SCOPE · TERMINAL
claude mcp add --scope user slack-notify -e SLACK_BOT_TOKEN=<YOUR_SLACK_BOT_TOKEN> -e SLACK_DEFAULT_CHANNEL=#general -e SLACK_MENTIONS=U1234567890,U0987654321 -- npx -y @mkusaka/mcp-server-slack-notify@latestClaude Code — global npm
CLAUDE CODE — GLOBAL NPM · TERMINAL
claude mcp add slack-notify -e SLACK_BOT_TOKEN=<YOUR_SLACK_BOT_TOKEN> -e SLACK_DEFAULT_CHANNEL=#general -e SLACK_MENTIONS=U1234567890,U0987654321 -- mcp-server-slack-notify
