Add getThread action to Slack tool

Problem

Currently there is no way to read thread replies in Slack. The getMessages action only returns top-level messages in a channel.

Proposed Solution

Add a getThread (or getReplies) action that uses the Slack conversations.replies API endpoint.

Parameters

• channel (required) - Channel ID where the thread exists
• threadTs (required) - Timestamp of the parent message
• limit (optional) - Max replies to return
• oldest / latest (optional) - Time range filters

Returns

{channel, threadTs, messages: [{ts, user, username, text, reactions}], hasMore}

Use Case

When searching messages or checking unreads, threads often contain important context. Being able to read thread replies is essential for understanding full conversations.