What is cs-mermaid?
cs-mermaid is a Claude Code mod by hex that draws mermaid flowcharts in replies inline, as coloured blocks and lines, and tells the model they draw. It is listed under Interface and has 50 GitHub stars.
| Type | Claude code mod |
|---|---|
| Author | hex |
| Repository | hex/claude-sessions |
| Popularity | 50 GitHub stars |
| Category | Interface |
| Security | Low risk (100/100) |
| Rank | #239 of 5,272 Claude Code mods; #96 in Interface |
| License | MIT |
| Last commit | 2026-10-17 |
| Stars this week | +3 |
| Hooks | 2 events |
| Sees | only the events it hooks |
| Draws on | AssistantMessage |
Is cs-mermaid safe to install?
cs-mermaid scores 100/100 on the MCPMods security check: Low risk. No checks raised a concern. It passed 8 of 8 checks.
Mod footprints come from claude plugin validate, which lists every event a mod hooks and every API call it makes without running it.
| Check | Result |
|---|---|
| No network access | Pass |
| Starts no processes | Pass |
| Writes no files or config | Pass |
| Doesn't read environment variables | Pass |
| Only sees the events it hooks | Pass |
| Doesn't drive Claude | Pass |
| Passes claude plugin validate | Pass |
| Has an open-source license | Pass |
API calls in its code
| Call | What it means |
|---|---|
$.config.list | |
$.fs.exists | reads files |
$.session.cwd | |
$.ui.resolve | draws interface |
How do I install cs-mermaid?
- Check your Claude Code version. Mods need Claude Code 2.1.287 or later and are on by default.
claude --version
- Read its footprint. This lists every event it hooks and every API call it makes, without running it.
git clone https://github.com/hex/claude-sessions claude plugin validate ./claude-sessions/mods/cs-mermaid
- Install it. Run this in your terminal, then /reload-plugins in an open session.
git clone https://github.com/hex/claude-sessions && claude --plugin-dir ./claude-sessions/mods/cs-mermaid
Or ask Claude to set it up
Paste this into Claude Code and it installs cs-mermaid for you:
Install the "cs-mermaid" Claude Code mod from https://github.com/hex/claude-sessions/tree/main/mods/cs-mermaid. Run claude plugin validate on it first and show me what it can access before you enable it.
More from hex/claude-sessions
This repository has 3 Claude Code mods on MCPMods.