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
Why Deterministic Workflows Outperform AI-Driven Orchestration for Agent Systems
A developer with a year of experience building agent systems shares that AI-driven orchestration failed reliably due to non-deterministic routing, compounding errors, cost explosion, and impossible debugging. Switching to deterministic workflows with code-based orchestration eliminated orchestration failures.
Monarch v3: NES-Inspired KV Paging for 78% Faster LLM Inference
Monarch v3 implements NES-inspired memory paging for transformers, achieving 78% faster inference (17.01 to 30.42 tok/sec) on a 1.1B parameter model with nearly zero VRAM overhead. The open-source algorithm splits KV cache into hot and cold regions with compression and promotion mechanisms.
claude-real-video: Free Tool to Make Claude Watch Videos with Perception Layer
claude-real-video adds a local perception layer so Claude sees camera moves, pacing, gestures, and voice emotion. Demo watches NVIDIA GTC 2026 keynote and narrates screen action. Free version available.
Skill Studio: Open-Source Desktop App for Managing Claude AI Agent Skills
Skill Studio is a free, open-source macOS desktop app that lets developers browse community skill repositories, preview documentation with markdown rendering, and install skills with one-click commands like npx skills add.