Lab Init: a safe place for project data

The Lab is where MasterMind keeps raw, project-specific material: codebase notes, captured patterns, signature profiles, anything with real names. It is local and gitignored; only the genericized, name-free output ever graduates to a shareable field pack. This exists because raw material sitting in a publishable tree is how confidential data leaks. Make it structural, not a habit.

Golden rule: patterns leave the quarantine, identities never do. Company/product/person/package names stay in lab/. Only the general rule, stripped of every name, goes into a field pack.

What it sets up

lab/
├── .denylist        ← your sensitive terms (gitignored); feeds the guards
├── raw/             ← untouched captures from a codebase
├── analysis/        ← working notes, `signature` profiles
└── MANIFEST.md      ← what's here, what's distilled, what's pending
.githooks/
├── pre-commit       ← blocks staged lab/ paths, denylisted terms, and real secrets
└── pre-push         ← scans every commit being pushed (catches --no-verify + old history)

Steps (idempotent: safe to re-run)

Run from the target repo root. The skill's files live in assets/ next to this SKILL.md.

1. Create the quarantine (preserving any existing content):

   • mkdir -p lab/raw lab/analysis
   • If lab/.denylist is missing, copy assets/denylist.template → lab/.denylist, then help the user fill it: company, product/app names, internal package scopes (@acme/*), colleague names, private domains/hosts. Never commit this file.
   • If lab/MANIFEST.md is missing, copy assets/MANIFEST.template.md → lab/MANIFEST.md.

2. Gitignore the quarantine: if lab/ isn't already ignored, append assets/gitignore-snippet.txt to the repo's .gitignore. Verify with git check-ignore lab/.

3. Install the guards:

   • mkdir -p .githooks && cp assets/pre-commit assets/pre-push .githooks/ && chmod +x .githooks/pre-commit .githooks/pre-push
   • git config core.hooksPath .githooks
   • If the repo already has a core.hooksPath or a hook manager (Husky, etc.), leave theirs in place. Tell the user, and offer to chain the guard into their existing pre-commit instead.

4. Prove it works (do this: a guard you haven't tested is a guard you don't have):

   • Stage a throwaway file containing a denylisted term and attempt a commit; confirm it's blocked, then unstage. Try staging a lab/ file; confirm the quarantine blocks it.

   • Now prove pre-push too: it's the layer that catches --no-verify and history committed before the guard existed, so the pre-commit test does not cover it. Use a local throwaway remote (no network, nothing is published: --dry-run still runs the hook):

     printf 'ACME_TERM internal notes\n' > leak-test.md   # swap in a real term from lab/.denylist
     git add leak-test.md && git commit --no-verify -m "temp: pre-push test"
     git init --bare /tmp/mm-throwaway.git
     git push --dry-run /tmp/mm-throwaway.git HEAD:refs/heads/mm-test   # must FAIL
     

     Expect ✖ BLOCKED: commit <sha> temp: pre-push test contains confidential terms:, then Push aborted … and a non-zero exit. If the push succeeds, the guard is not live: check git config core.hooksPath, that .githooks/pre-push is executable, and that the term is in lab/.denylist (the hook scans every file type, but skips lab/ itself. That's the quarantine).

   • Clean up: --soft, never --hard: a hard reset here would discard any uncommitted work in the user's repo. git reset --soft HEAD~1 && git restore --staged leak-test.md && rm -f leak-test.md && rm -rf /tmp/mm-throwaway.git

5. Report what was created/changed, and remind: raw data → lab/; only genericized output ships.

Guardrails

• The guards are generic and safe to publish; the denylist is not: terms live only in the gitignored lab/.denylist. Never bake a real name into a hook, .gitignore, or the manifest (use *-glob patterns).
• Escape hatch: ALLOW_SENSITIVE=1 git commit … bypasses the guard for a deliberate, reviewed case.
• Not a substitute for review: the guard catches known terms and obvious secrets, not everything. Read a diff before pushing to any public remote (core/agent-loop.md).
• Distilling lab/ into a pack is a separate step (the levelup capture flow), this skill only stands up the safe container.