"It works on my machine" is still one of the most common developer problems in 2026. When you clone a repo, switch branches, or onboard to a new project and something breaks, the first 20 minutes are usually wasted guessing. The env-doctor skill changes that.
Quick Answer: Env-doctor is an AI skill designed to diagnose development environment issues by systematically checking runtime versions, dependencies, environment variables, database connections, port conflicts, and build artifacts, providing actionable steps to resolve problems.
What env-doctor does
Env-doctor is a SKILL.md skill that systematically diagnoses why your development environment isn't working. Instead of throwing cryptic error messages at you, it works through a structured checklist:
Runtime versions: Is the correct version of Node, Python, Ruby, Go, or Java installed? Does it match what the project expects?
Dependencies: Are all packages installed? Are there version conflicts? Is the lock file in sync with the manifest?
Environment variables: Are required .env variables set? Are they pointing to the right values?
Database connections: Can the app connect to its database? Is the database running?
Port conflicts: Is the expected port already in use by another process?
Build artifacts: Do compiled files exist? Are they stale?
How it works
When you ask Claude "why won't this project start" or "diagnose my environment," the env-doctor skill activates and runs through each category in order. It reports what it finds at each step — what's correct, what's missing, and what's misconfigured.
The output is actionable: instead of a wall of errors, you get specific things to fix in priority order.
Installing env-doctor
# Download from Agensi
# Unzip to your skills directory
unzip env-doctor.zip -d ~/.claude/skills/
Also works on OpenClaw
cp -r ~/.claude/skills/env-doctor ~/.openclaw/skills/ ```
Free on Agensi.
When to use it
Use env-doctor whenever you hit a "doesn't start" situation: cloning a new repo, pulling changes that update dependencies, switching between branches with different requirements, onboarding to a team project, or returning to a project after time away.
It's one of those skills that you don't need every day, but when you need it, it saves 30 minutes of frustration.
Get env-doctor and other developer skills on Agensi.