Slack MCP Server

Instructions

Implementation Reference

• slack_mcp/server.py:347-365 (handler)

  The main MCP tool handler function for 'get_channel_history'. It instantiates SlackClient and delegates to its get_channel_history method, serializing the result to JSON.

  @mcp.tool()
  async def get_channel_history(
      channel: str, limit: int = 100, oldest: Optional[str] = None, latest: Optional[str] = None
  ) -> str:
      """
      Get message history for a Slack channel.
  
      Args:
          channel: Channel ID
          limit: Maximum number of messages to return
          oldest: Only messages after this timestamp
          latest: Only messages before this timestamp
      """
      try:
          client = SlackClient()
          result = await client.get_channel_history(channel, limit, oldest, latest)
          return json.dumps(result, indent=2)
      except Exception as e:
          return json.dumps({"error": str(e)}, indent=2)

• slack_mcp/server.py:132-149 (helper)

  Helper method in SlackClient class that makes the actual Slack API call to conversations.history endpoint.

  async def get_channel_history(
      self,
      channel: str,
      limit: int = 100,
      oldest: Optional[str] = None,
      latest: Optional[str] = None,
      inclusive: bool = True,
  ) -> Dict[str, Any]:
      """Get message history for a channel."""
      params = {"channel": channel, "limit": limit, "inclusive": inclusive}
  
      if oldest:
          params["oldest"] = oldest
  
      if latest:
          params["latest"] = latest
  
      return await self._make_request("GET", "conversations.history", params=params)