Commit Guard

Execute BEFORE creating git commits. Combines size checking, coherence analysis, and branch protection.

Config

Read from .opencode/config.json → skills.commit-guard (defaults shown):

•max-files: 15, max-lines: 500, max-file-lines: 300
•similarity-threshold: 0.3, auto-split: true, warning-only: true
•protected-branches: ["main", "master"]
•auto-push: true, branch-name-max-length: 50

Workflow

1. Analyze: Run git diff --cached --numstat, count files/lines, group by directory/type/naming

2. Check thresholds: Files/lines/single-file > limits → Warn

3. Calculate coherence (0.0-1.0): Same dir +0.4, same type +0.2, related names +0.3

4. Determine strategy:

Unrelated (coherence < 0.3):

•Show groups, ask to split
•If yes: Each group → separate feature branch (use question tool per group)
•For each: Stash all, create branch, restore group files only, commit, push individually
•Result: N parallel branches

Related (coherence >= 0.3) with size warnings:

•Ask to split into smaller commits
•If yes: Ask for branch ONCE, create branch, multiple commits on SAME branch, push once
•Result: 1 branch with N commits

No warnings or declined split:

•Single commit on current/new branch

Branch creation (if on protected branch):

•Extract: Ticket (GH-123, JIRA-456, #789), Type (fix→bugfix/, add→feature/, urgent→hotfix/), Description (group context or 2-4 words)
•Generate 2 suggestions: {type}/{ticket}-{description}
•User chooses (use question tool): Suggestion 1 (Recommended), Suggestion 2, Protected branch (NOT recommended), Custom

Commit message:

•If ticket in branch: Prefix with {TICKET}: {message}
•Unrelated: Distinct messages per group
•Related: Consistent message series

Examples

Unrelated → 3 Branches:

code

auth/login.ts, ui/button.css, docs/README.md → Coherence 0.15
→ feature/auth-login: "Fix login authentication"
→ feature/ui-button-style: "Update button styling"
→ feature/docs-readme: "Update README"

Related Large → 1 Branch:

code

api/service.ts (600), service.test.ts (150), api.d.ts (50) → Coherence 0.9, 800 lines
→ feature/api-service-refactor:
  "Refactor API service implementation"
  "Add tests for API service refactor"
  "Update API type definitions"

Clean → Direct:

code

Button.tsx (45), Button.test.tsx (30) → 2 files, 75 lines, coherence 0.9
→ Proceed directly on current branch