slack-messaging

name	slack-messaging
description	Send a message or notification to a Slack channel or thread using the gateway's configured tokens.
version	1.0.0
author	Timsonner
license	MIT
metadata	{"hermes":{"tags":["slack","gateway","messaging","notifications","multi-agent"],"related_skills":["multi-agent-coordination","cli-wrapper-design-and-debugging"]}}

Slack Messaging Skill

This skill provides guidelines and tools to send messages, notifications, or replies to Slack channels and threads from the local command-line or agent context.

When to use this skill

• Use when the user requests to send a message, status update, or notification to Slack.
• Use when you need to post a status report or automated feedback to a specific Slack channel.
• Use when responding to a specific Slack thread.

How to use this skill

1. Ensure the gateway's .env configuration file exists and has SLACK_BOT_TOKEN.
2. Execute the CLI script send_slack.py located at the root of the repository:

   python send_slack.py "Your message text here"
   

Commands

Send message to default home channel (typically #general)

python send_slack.py "Message content"

Send message to a specific channel (by name or ID)

python send_slack.py --channel "random" "Hello random channel!"
python send_slack.py --channel "C0B8U40L6PL" "Hello custom channel ID!"

Reply to a thread in a channel

python send_slack.py --channel "general" --thread "1780829722.426309" "Thread reply message"

Pipe stdin contents

cat build_output.log | python send_slack.py

Mentioning Users and Bots

When sending messages via the API, plain text mentions like @Hermes or @Antigravity will not trigger notifications or gateway events. You must use the Slack Member ID in the <@MEMBER_ID> format:

• To mention Hermes, use: <@U0B8CNSPWB1>
• To mention Antigravity, use: <@U0B8SBAFB8W>

Example of thread reply:

python send_slack.py --channel "C0B8U3ZGE7L" --thread "1780831489.381079" "<@U0B8SBAFB8W> Hello Antigravity!"

Multi-Agent Collaboration & Authorization

When initiating agent-to-agent communication (e.g., Hermes invoking Antigravity in a Slack thread), keep the following in mind:

1. The Authorization Gate (SLACK_ALLOWED_USERS)

The Slack gateway filters incoming messages by user ID to enforce authorization. By default, it blocks messages from unauthorized bots and users.

• If Hermes needs to send a message to trigger Antigravity, Hermes' Member ID (U0B8CNSPWB1) must be added to the comma-separated SLACK_ALLOWED_USERS list inside the gateway's .env file.
• Example configuration:

  SLACK_ALLOWED_USERS=U0B8CKH5SVD,U0B8CNSPWB1
  

• Gateway Restart Required: If .env is modified, the gateway listener process (gateway.py) must be restarted to load the updated list.

2. Identifying Active Processes

To find or manage running gateway processes on the Windows host, use PowerShell commands from the terminal:

• List running gateways:

  powershell -Command "Get-CimInstance Win32_Process -Filter \"CommandLine LIKE '%gateway.py%'\" | Select-Object CommandLine, ProcessId"
  

• Force-stop a gateway process:

  powershell -Command "Stop-Process -Id <ProcessId> -Force"
  

3. Interactive Tool Approvals (YOLO Mode)

When Antigravity attempts to run shell commands in any thread (and YOLO mode is disabled), it triggers a synchronous BeforeTool hook that prompts you with Approve/Deny buttons directly in Slack.

• Enable YOLO Mode (Disable prompts): Run !yolo inside the Slack thread.
• Disable YOLO Mode (Enable prompts): Run !yolo again.
• Handling Requests: Click Approve 🟢 to let the tool execute, or Deny 🔴 to reject it.