fstack installs natively in Claude Code, GitHub Copilot, Codex, Pi, and oh-my-pi, and through the skills CLI in any other agent. Start a new session after installing so your agent loads the skills.
/plugin install fstack --marketplace mastro993/fstack
On Claude Code older than 2.1.275
/plugin marketplace add mastro993/fstack
/plugin install fstack@fedemas
In Copilot CLI:
copilot plugin marketplace add mastro993/fstack
copilot plugin install fstack@fedemasIn VS Code, turn on the chat.plugins.enabled setting. VS Code then loads plugins installed with Copilot CLI; without the CLI, run Chat: Install Plugin from Source and enter https://github.com/mastro993/fstack.
codex plugin marketplace add mastro993/fstack
codex plugin add fstack@fedemaspi install git:github.com/mastro993/fstackAdd -l to install for the current project only. Pi ships without subagents, which ux-stress-test needs, so add a subagent package from the Pi package gallery before you run it.
omp plugin marketplace add mastro993/fstack
omp plugin install fstack@fedemasAdd --scope project to install for the current project only.
The skills CLI installs the skills into Cursor, OpenCode, Gemini CLI, Windsurf, and many more agents:
npx skills add mastro993/fstackIt asks which skills and agents you want, and installs into the current project unless you add -g. To skip the questions, name them:
npx skills add mastro993/fstack --skill pr-babysit --agent cursor -g -y| Skill | What it does |
|---|---|
| pr-babysit | Watches a pull request through CI and review. Your agent fixes failing checks, addresses or answers review comments (bots included), pushes, re-requests review, tells you when the PR is ready to merge, and keeps watching until it lands. |
| pr-ship | Ships a change. Your agent opens the PR or marks your draft ready, babysits it with pr-babysit, keeps asking the automated reviewers for another pass until one comes back clean, and merges it. |
| ux-stress-test | Five first-time-user personas try to reach first success in your web app in a real browser. Your agent ranks the friction they hit, fixes what you choose, and reruns the personas blind to prove the fixes, or opens issues for later. |
Your agent waits on GitHub without burning turns and reacts as things happen:
- 🔴 Failing check: reads the failed log once, fixes the root cause, reruns infra flakes once, and stops after two failed attempts.
- 💬 Review comment: fixes what's clear, answers questions from the code, checks bot claims before acting on them, and asks you about design calls or pushback.
- 🔁 After a push: replies on each thread with the fix commit, re-requests review, and leaves resolving threads to the reviewer.
- 🔀 Base moved: when another PR lands and leaves this one conflicting or behind, merges the base in (never rebases or force-pushes), resolves the conflict, and asks you when both sides disagree.
- ✅ Ready: tells you, then keeps watching until the PR is merged or closed, or you say stop. It never merges unless you asked; landing it is pr-ship's job.
Ask only to be told ("let me know when CI finishes") and it reports without touching anything.
Needs: an authenticated gh CLI, git, python3, and a checkout of the PR's branch to push fixes from.
Try it: ask your agent to "babysit PR #42" or "watch my PR and fix whatever CI or review throws at it".
Say the word and your agent takes the change all the way to the base branch:
- 🚀 Open: commits and pushes the change if needed, then opens the PR from your template, or marks your draft ready.
- 🍼 Babysit: hands failing checks, review threads, and a moving base to pr-babysit.
- 🤖 Review rounds: gets each automated reviewer on the repo (CodeRabbit, Pullfrog, Claude, Copilot, Codex, Bugbot, Greptile, and more) to review the latest push, fixes what they find, and asks again until a round comes back clean. If three rounds of fixes still turn up new findings, it asks you whether to keep going.
- ✅ Merge: squash-merges when the repo allows it (otherwise with the method it allows), pinned to the commit that passed, and only through the repo's rules, never with
--admin.
Needs: pr-babysit (install both) and everything it needs.
Try it: ask your agent to "ship it", "get this into main", or "merge #42".
The personas each break your app in their own way:
- ⏱️ Impatient: skims, clicks the biggest button, and quits at the first error.
- 🤨 Skeptic: wants to know what they're signing up for before handing over anything.
- 📱 Mobile: small screen, touch only, slow 3G.
- 🌍 Non-native: reads your copy literally.
- 🔨 Breaker: submits junk, double-clicks, and goes back mid-flow.
Needs: subagents, Chrome, browser-use (uv tool install browser-use) or playwright-cli as a fallback, and the app's source code.
Try it: ask your agent to "stress-test the signup flow" or "run a UX stress test before launch".
MIT © Federico Mastrini