Claude Code Slack: Delegate Coding Right From the Chat

Claude Code in Slack works like this: you mention @Claude with a task in a channel, it detects the coding intent, spins up a Claude Code session on the web, and posts progress back into your thread — finishing with buttons to view the session or create a pull request. I'm Evgeny, and I love this feature for one unglamorous reason: the bug report and the bug fix finally live in the same conversation.

How does Claude Code in Slack actually work?

It's built on the Claude for Slack app with one clever addition: intelligent routing. When you @mention Claude, it analyzes the message — is this a coding task or a regular question? Coding tasks get routed to Claude Code on the web, where a full cloud session runs against your GitHub repository. Nothing executes inside Slack itself; Slack is the front desk, the workshop is at claude.ai/code.

How it reads context from the thread

Claude gathers context from the thread you mentioned it in (or recent channel messages), so an error screenshot your colleague posted two messages up becomes part of the briefing. While it works, status updates land in the thread, and when it's done, you get a summary plus action buttons.

Is this the same as a Slack MCP server?

No — and the distinction trips people up. This is Anthropic's first-party Claude for Slack app, where Slack triggers a cloud coding session. A Slack MCP server is a different, do-it-yourself route: it gives a Claude Code session on your own machine tools to read and post Slack messages. The official integration is the no-setup path covered here; the MCP route is for plumbing Slack into a local session.

How do you connect Claude Code to Slack?

Four boxes to tick, per the docs: a Claude plan with Claude Code access (Pro, Max, Team, or Enterprise), Claude Code on the web enabled, a GitHub account connected with at least one repository authenticated, and your Slack account linked to your Claude account. Notice what's not on the list: any programming skill.

you ▸ @Claude the signup form crashes when the email has a
      plus sign — thread above has the error. Fix it in the
      webapp repo and prepare a PR.

claude ▸ Starting a Claude Code session… reading the thread.
claude ▸ Done. Summary in thread. [View Session] [Create PR]

Code only or Code + Chat: which routing mode?

'Code only' sends every @mention straight to a Claude Code session — pick it if your team uses Claude in Slack purely as a coding bot. 'Code + Chat' lets Claude decide per message: coding tasks go to Claude Code, while writing, analysis and general questions get a normal chat answer — one @Claude entry point for everything. Misrouted? There's an undo: a 'Retry as Code' button when you wanted a coding session, and the reverse option in the thread when you didn't.

What happens after you hit send?

The flow is: detection, session creation on claude.ai/code, progress updates in the thread, then a completion summary with buttons. 'View Session' opens the full transcript in your browser, where you can continue the conversation or ask for changes. 'Create PR' turns the session's changes into a GitHub pull request. 'Change Repo' fixes the case where Claude guessed the wrong repository — though including the repo name in your request prevents that in the first place. Everything runs under your own Claude account, counts against your plan's limits, and shows up in your session history on the web.

What are the limits right now?

Current constraints from the docs: GitHub repositories only, one pull request per session, your individual rate limits apply, and teammates without Claude Code on the web access get plain chat answers instead of coding sessions. Slack shines when the context already lives in a discussion or you want to fire off a task asynchronously; for file uploads or long interactive work, go to the web directly.

The habit to build: next time someone reports a bug in Slack and you think 'I'll deal with that tonight' — don't. @Claude it on the spot, with the thread as context, and review a finished pull request over your evening tea instead. Delegation beats memory every single time.