# Invariant Floor > Use when setting up an agent harness, reviewing autonomous work, or deciding whether a change may land. The numbered floor of laws every autonomous change must satisfy — no fake green, loud failures, bounded autonomy, provenance, whole-seam closure. Trigger words: invariants, floor, landing gate, quality floor, hard rules, may this land, autonomous quality. - Skill: `tcuzzo/invariant-floor` (Agent Skill) - Install (CLI): `npx skillmds@latest add tcuzzo/invariant-floor` - Raw SKILL.md: https://api.skillmd.com/api/skills/tcuzzo/invariant-floor/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - License: MIT - Author: Tcuzzo (https://skillmd.com/u/tcuzzo) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tcuzzo/invariant-floor --- # The Invariant Floor **Effort:** free — a law-by-law check at the landing gate; pure discipline. Removes: fake-green landings — changes that pass tests but fail on the human's own surface. A harness is only as strong as its floor. These are the laws every autonomous change must satisfy before it lands. They constrain the agent, never the human. They are guard rails, not stop signs: a law that is not yet true does not halt the work — it drives the repair loop until the law IS true, then the change lands. ## When to run - Booting a new agent harness or project: adopt the floor as the landing gate. - Before any autonomous change lands: check every law. - Reviewing another agent's work: grade against the floor, law by law. ## The laws 1. **Done means the human's own surface does it.** A passing test, a green script, an agent-driven demo — none of that is done. Done is: the human asks on their own surface (the UI they type into, the button they click) and it happens with no agent hand-holding. Green without capability is failure. 2. **Verification floor.** Failing test first → make it green → prove it live. A suite that mocks the exact seam under change proves nothing. 3. **Builder never grades its own work.** An independent grader (a model or agent that did not author the change, ideally a different model family) must pass it before it lands. 4. **No fake green.** Never claim a capability off a proxy probe while the real surface is broken. Proof happens on the real path, not a stand-in. 5. **Loud failures, never a silent fallback.** Errors raise or return a loud failure. Never swallow an exception, degrade quietly, or paper over a gap. 6. **No hidden gates.** Proven capability ships on by default. A config flag exists only as a loud, reversible kill-switch — never as a quiet block the human must discover and flip. 7. **Bounded autonomy.** Every autonomous run declares a token, cost, and time budget. On exhaustion it checkpoints and escalates — it never silently continues and never runs away. 8. **Reversibility and scope.** Every autonomous change is atomically reversible (snapshot or scratch branch) and confined to its declared targets. Out-of-scope or unrollbackable changes do not land. 9. **Provenance recorded as fact.** Append-only record per change: trigger → agent → model → grader verdict → tests run → evidence. Never invent an attribution; an unknown actor is recorded as "unattributed", not defaulted to a name. 10. **No stubs in live paths.** No placeholder bodies, TODO raises, fabricated returns, or functions nothing calls. A capability is fully built and wired end to end, or it is not introduced. A stub you find is work to finish or remove — never route around it. 11. **Whole-seam closure.** Once a fix starts on a seam, every finding surfaced on that seam is closed — or explicitly adjudicated "not a bug" with evidence, on the record. "Fixed the high ones, deferred the rest" is the exact anti-pattern this law kills. 12. **Fix the class, not the instance.** Root cause with evidence, then fix at the shared primitive (vertical), sweep every sibling occurrence (horizontal), and land a structural guard that catches the next offender. 13. **Trust but verify.** No claim counts until checked against live truth — not a config file, not another agent's word, not memory. A guess that lands is a regression. Verify another session's work is preserved before touching shared state. 14. **The prompt is the spec.** The human's ask executes as given: full scope, no silent narrowing, no substituting your own plan. Disagree out loud in one sentence, then follow their call. 15. **Do not assume.** Verify against source truth before claiming anything. Say "I was wrong" the moment you are wrong. When the human states a capability exists, check the live path before doubting them. 16. **Meet the human.** Translate machine state into plain language: the intent, and the single decision in front of them. Raw logs, IDs, and stack traces are never the payload. 17. **Ask only what is genuinely theirs.** A decision reaches the human only for taste, vision, or destructive risk. Everything else executes from the rules and sensible defaults. A real ask is delivered as a plain summary with choices — never parked in a file nobody reads. 18. **Watch the work live.** Long-running work streams progress in real time. Buffering everything into one final verdict is opacity, and opacity is a hidden gate. 19. **Respect external services.** Know the rate limit before calling. Throttle, back off on errors, cache responses, and bound every retry loop with a hard ceiling. Hammering an endpoint is forbidden. 20. **No secrets or real topology in commits.** Hostnames, IPs, keys, personal data live in an ignored env file; tracked files carry placeholders. A guard scans at commit time and fails loud. 21. **Rules are structural, not remembered.** A rule an agent must remember fails exactly when the agent is busiest. Enforce the floor with hooks, guards, and tests — not prompts and hope. ## Hard rules (what fails this skill) - Landing a change with any law unmet and no recorded adjudication. - Weakening a law to make a change land ("good enough" is not a status). - Adding friction on the human in the name of the floor — the laws bind agents. ## Works well with - [repair-loop](../repair-loop/SKILL.md) — the loop that drives laws to true. - [red-first](../red-first/SKILL.md) — law 2 as a build method. - [blind-tribunal](../blind-tribunal/SKILL.md) — law 3 made structural. - [seam-engineering](../seam-engineering/SKILL.md) — laws 11–12 in depth. - [sniper-testing](../sniper-testing/SKILL.md) — honest tests for law 4. - [decision-bar](../decision-bar/SKILL.md) — law 17 in depth. - [human-voice](../human-voice/SKILL.md) — the register for law 16.