Fromzero

---
name: fromzero
description: 'Use when the user wants to replace a greenfield attempt with a clean pad carrying only verified requirements. Preserves the old attempt in VCS history. Not for rebuilding from primitives — use from-first-principle. Requires a committed, VCS-recoverable current attempt.'
disable-model-invocation: true
---

# Fromzero

## Contract

| Field | Bound contract |
|---|---|
| Trigger | The user wants to replace a greenfield attempt with a clean pad carrying only proven requirements. |
| Authority | Restrict changes to VCS-tracked targets, show the exact set before mutation, and use version control as the recovery path. Human-only: act only on explicit human invocation. |
| Side effect | A new greenfield attempt on a clean pad; the old attempt remains recoverable through VCS. |
| Done | A new greenfield attempt exists carrying only verified requirement statements, and the old attempt is reachable in VCS history. |

## Not for

- Rebuilding a design from primitives — use from-first-principle.
- Continuing an existing attempt with fixes — this replaces, it does not patch.
- Operating without a committed, VCS-recoverable current attempt — the old attempt must survive in history.

## Inputs

- The current greenfield attempt, which must be under version control and committed.
- A list of proven requirements. A requirement is proven only when it has been verified (tested, accepted, or otherwise demonstrated). Speculative or unverified scope is not proven.

## Procedure

1. Verify the current attempt is committed and recoverable through version control. If any uncommitted or untracked work exists, stop and require the human to commit or discard it first. Done when: the working tree is clean and the attempt is in VCS history.

2. Filter requirements to verified only. Carry only requirements that have been verified; discard unproven, speculative, or accumulated scope. Done when: the proven-requirements set is listed and each entry is verified.

3. Branch from the recoverable commit to clear the working surface. The old attempt survives in VCS history while the working surface is cleared on the new branch. Do not use an unspecified reset alternative; the mutation is a branch creation followed by working-surface clearance on that branch. Done when: the working surface is clear on the new branch and the old attempt is reachable in VCS.

4. Write the requirement list into the new pad. Write only the proven requirements as statements. Do not reintroduce discarded scope. Done when: the new pad contains only verified requirement statements.

## Failure and recovery

- Current attempt not committed or not VCS-tracked: stop before mutation; require the human to commit. No files change.
- Unverified requirements mixed: stop; do not carry unproven scope into the new attempt.
- Non-mutation fallback: when any precondition fails, no target is changed. Report the blocked precondition and the exact recovery step the human must perform. Do not substitute an unspecified reset alternative.
- Partial-result rule: never leave a half-replaced pad. The old attempt must be recoverable through VCS before any working-surface mutation begins.

## Output

A new greenfield attempt on a clean pad carrying only verified requirement statements, with the old attempt recoverable through VCS history.