Env Doctor

Diagnoses why your project will not start by systematically checking runtime versions, dependencies, environment variables, databases, ports, and build artifacts.

Install
cmdop skills install agensi-env-doctor

Env Doctor is a skill published by agensi that performs systematic startup diagnosis when a project fails to launch and the error messages are not informative enough to act on. Rather than surfacing one error at a time, it works through potential causes in a logical order, giving a structured picture of what is wrong and how to fix each issue.

The skill checks runtime versions across Node, Python, Ruby, and Go, so version mismatches are caught early. It then inspects missing or outdated dependencies, which covers the common case where a lock file is out of sync with the installed packages. Required environment variables are verified for presence, catching the silent failures that come from a missing .env file or a misconfigured deployment. Database connections are probed to distinguish application bugs from infrastructure problems. Port conflicts are identified so that a blocked port is not mistaken for a service crash. Finally, stale build artifacts are flagged, which can cause hard-to-reproduce failures after a dependency upgrade or a branch switch.

This skill is suited to development environments where project startup failures need to be triaged quickly and the root cause is not immediately clear. It is not a runtime monitoring tool and does not diagnose issues that occur after a project has successfully started.

Use cases

  • Diagnose why a local development server refuses to start after cloning a repository
  • Identify which required environment variables are missing before a deployment
  • Detect runtime version mismatches across Node, Python, Ruby, or Go
  • Find port conflicts blocking a service from binding at startup
  • Spot stale build artifacts left over after switching branches or upgrading dependencies
  • Verify database connection availability as part of environment setup

When to use it

  • A project fails to start and the error output is ambiguous or unhelpful
  • Onboarding to a codebase and the local environment needs a full health check
  • A CI or staging environment is behaving differently from local and root cause is unknown
  • Multiple potential startup issues need to be triaged in one pass rather than one at a time

When not to use it

  • The project starts successfully but exhibits runtime bugs — this skill targets startup failures only
  • Continuous production monitoring is needed — this is a diagnostic skill, not a monitoring agent
  • The runtime in use is not Node, Python, Ruby, or Go — other runtimes are not listed as covered
  • A package registry or installation step is required — no package identifier or install mechanism is provided