Slack Message Formatter: Fix Claude's Broken Markdown in Slack
What This Tool Solves
When Claude generates messages for Slack, the formatting breaks because Slack uses "mrkdwn" instead of standard Markdown. This results in bold text showing as asterisks, links appearing as raw URLs, and tables becoming unreadable.
How It Works
The skill handles the conversion process in two ways:
- Browser Preview Method: You ask Claude to write a Slack message, it generates Markdown, the skill converts it to rich HTML and opens a browser preview. You then use Cmd+A, Cmd+C, Cmd+V to copy-paste into Slack with formatting preserved.
- API Method: The tool has a webhook path for sending via API using proper mrkdwn with
*bold*,_italic_, and<url|text>formatting.
Key Technical Details
The developer tested existing converters first and found 13 hard failures including broken tables, stripped checkboxes, and unescaped script tags. This prompted building a more reliable solution.
The tool has 172 tests, zero dependencies, and comes as a single file. It supports features that mrkdwn doesn't natively handle, including tables, nested lists, and checklists via the browser copy-paste method.
Installation
Install via Claude plugin marketplace:
claude plugin marketplace add karanb192/slack-message-formatter
claude plugin install slack-message-formatter@slack-message-formatterThe GitHub repository is available at https://github.com/karanb192/slack-message-formatter.
📖 Read the full source: r/ClaudeAI
👀 See Also
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