Harbormaster runs in a local Codex task on the computer you want to inspect. It maps listening ports to their processes and projects, flags reservation collisions, records vanished services, and safely stops one explicitly selected process. Hosted ChatGPT cannot access your computer's process table.
Install
- 1Add it in ChatGPT
Open Plugins in the ChatGPT sidebar (web or desktop), search for “Harbormaster” and select +. You'll be asked to sign in to any connected service on first use. Then type @ in a chat to call it.
Skills 1
- harbormaster
Diagnose local port collisions, identify the project or process holding a port, reserve ports, inspect service history, or safely free exactly one explicitly authorized local listener. Use for localhost conflicts, vanished dev servers, port ownership, reservations, and anti-killall process control.
Things to ask
- “In Codex, show me what is using my local ports.”
- “In Codex, who owns port 3000?”
- “In Codex, why did my dev server disappear?”
Related
SuperpowersPlan, develop, and debug codeplugin · by Jesse Vincent · 294k stars
ShopifyBuild and manage your storeplugin · by Shopify · 7.2k stars