This file provides guidance to agents when working with code in this repository.

npm run build        # bundles bin/cli.ts → dist/cli.mjs via tsdown with minification
npm run lint         # oxlint
npm run lint:fix     # oxlint --fix
npm run fmt          # oxfmt
npm run fmt:check    # oxfmt --check
npm run check-types  # tsc --noEmit
npm test             # vitest run

acai is an opinionated CLI tool that generates git commit messages using already-installed AI tools (Claude Code, OpenAI Codex).

1. Preflight — verify git repo and selected provider CLI availability
2. File staging — prompt user to stage files if nothing is staged (interactive multi-select grouped by status)
3. Context gathering — collect staged diff, stat, file list, and last 10 commit messages (for style inference)
4. Generation — spawn provider CLI subprocess with system prompt (commit history for style) and user prompt (diff/stat/files), parse response
5. Review loop — user can accept, edit in $EDITOR, revise with feedback (re-runs generation), copy to clipboard, or cancel

• bin/cli.ts — entry point and interactive flow orchestrator using @clack/prompts
• src/providers.ts — provider interface, registry (claude + codex), ensureProvider() and generateCommitMessage() functions
• src/prompts.ts — shared prompt-building logic (buildSystemPrompt, buildUserPrompt) and intelligent diff truncation at hunk boundaries
• src/git.ts — git operations wrapper (diff, staging, commit via temp file to avoid shell escaping)
• src/args.ts — CLI argument parsing via node:util parseArgs; supports -p/--provider, -m/--model, -y/--yolo flags and ACAI_PROVIDER/ACAI_MODEL env vars

• Commit messages are written via temp file (git commit -F) rather than -m flag to avoid shell escaping issues
• Diff truncation preserves whole hunks rather than cutting mid-hunk
• Commit style is inferred from repo history (system prompt includes recent commits) rather than hardcoded conventions
• Clipboard support detects platform: pbcopy (macOS), xclip/xsel (X11), wl-copy (Wayland)