What is env-doctor?
env-doctor is a Claude Code mod by mercynet that read-only preflight of a dev environment at session start: stopped compose services, missing node_modules for MCP servers, empty cache files and required paths. Never fixes anything, it. It is listed under Cost & usage and has no public popularity data yet.
| Type | Claude code mod |
|---|---|
| Author | mercynet |
| Repository | mercynet/my-claude-mods |
| Popularity | no public popularity data yet |
| Category | Cost & usage |
| Security | Low risk (84/100) |
| Rank | #3,972 of 5,272 Claude Code mods; #749 in Cost & usage |
| Last commit | 2026-10-09 |
| Hooks | 2 events |
| Sees | only the events it hooks |
| Draws on | nothing |
Is env-doctor safe to install?
env-doctor scores 84/100 on the MCPMods security check: Low risk. Things to review: starts processes outside the sandbox. It passed 6 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 processes outside the sandbox | Review |
| 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 |
| No license detected | Note |
API calls in its code
| Call | What it means |
|---|---|
$.clock.after | |
$.command.register | |
$.fs.exists | reads files |
$.fs.read | reads files |
$.fs.stat | reads files |
$.process.run | runs processes |
$.session.root | |
$.ui.log | draws interface |
$.ui.status | draws interface |
$.ui.toast | draws interface |
How do I install env-doctor?
- 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/mercynet/my-claude-mods claude plugin validate ./my-claude-mods/env-doctor
- Install it. Run this in your terminal, then /reload-plugins in an open session.
claude plugin marketplace add mercynet/my-claude-mods && claude plugin install env-doctor@local-mods
Or ask Claude to set it up
Paste this into Claude Code and it installs env-doctor for you:
Install the "env-doctor" Claude Code mod from https://github.com/mercynet/my-claude-mods/tree/main/env-doctor. Run claude plugin validate on it first and show me what it can access before you enable it.
More from mercynet/my-claude-mods
This repository has 6 Claude Code mods on MCPMods.
- context-forecast: Forecast of the context window with a clear-or-compact score, usage limits, cross-session calibration and guided compact (Low risk)
- graph-sync: Keeps a code knowledge graph fresh: after code edits, runs an AST-only update command in the background when the turn en (Low risk)
- lean-context: Measures and, once approved, strips configured sections of the project instruction file from the Claude Code context whi (Review before installing)
- session-banner: Shows a plain-text logo with a gradient and one shimmer sweep above the prompt when a session starts, until the first pr (Review before installing)
- spec-band: A band above the prompt showing the active spec of the current branch: task progress, STATE.md age and phase, and a warn (Review before installing)