git:20261012.45e9b2b to git:20261014.40b9a45

# half-fixed

> Read by Claude Code as CLAUDE.md and by Codex and other agents as AGENTS.md (a symlink).

A git-history scanner that finds fixes made to some sibling implementations but not the others, shipped as Agent Skills. Bun for development, a Node 18+ runtime for the shipped CLI.

## Quick reference

```bash

bun install

bun run test # bun:test suites

bun run test:coverage # 100% line and function coverage of src/, then check:fallback

bun run check:metadata # versions, Bun pin, skill frontmatter in step

bun run build:fallback # rebuild skills/half-fixed/scripts/half-fixed.js

bun run half-fixed -- scan /path/to/repo # run the CLI from source

```

## Layout

```

bin/half-fixed.js # npm bin, wires runCli to the process

src/

├── cli.js # arguments, commands, exit codes

├── scan.js # the scan itself, confidence, exemptions

├── diff.js # git log -p parser, change blocks, window selection

├── groups.js # sibling group discovery, glob matching

├── normalize.js # whitespace normalization, window search

├── git.js # git helpers, cached file reads at a revision

├── config.js # .half-fixed.json

├── report.js # text output

└── version.js # VERSION, bumped by the release script

skills/

├── half-fixed/

│ ├── SKILL.md # agent workflow: scan, triage, fix

│ ├── references/ # triage.md, fixing.md (loaded on demand)

│ └── scripts/half-fixed.js # bundled CLI (bun build --target=node), committed, never edited by hand

└── house-style/SKILL.md # match a repo's PR and commit conventions

scripts/ # build, check, and release tooling (plain Node, shared helpers in lib.js)

test/ # bun:test suites that build throwaway git repos

```

## Rules

- **Zero runtime dependencies.** Copied skills run the bundle with plain `node`, so there's no install step. Node 18 is the floor: don't use APIs newer than that in `src/`.

- **Every `git` call is synchronous.** Under Bun, an async child process whose exit overlaps a synchronous spawn can lose its `close` event and hang. See `gitLines` in `src/git.js`.

- After changing anything in `src/` or `bin/`, run `bun run build:fallback` and commit the regenerated bundle. CI fails if it's stale.

- The scanner reports candidates. Judgement lives in the skill instructions, not in more heuristics.

- Every heuristic change gets a test in `test/scan.test.js` that builds the repository shape it's about, and a before-and-after scan of a real repository (prism-php/prism is the reference case).

- Conventional Commits. No version bumps outside `bun run release`. User-visible changes get a CHANGELOG entry under Unreleased.