commitbrief

CommitBrief

LLM-powered local code review for git diffs. Run a "second pair of eyes" review on your staged changes, a specific file, a single commit, or a PR-style three-dot range — without leaving the terminal.

Pick a provider once, then:

commitbrief                                # review your staged changes
commitbrief diff HEAD                      # review working tree vs HEAD
commitbrief diff main...feature/x          # review a PR
commitbrief --unstaged --dir app/Models    # narrow any scope to a directory

Output is rendered as colored markdown in the terminal, plain markdown to a file, or strict JSON for tooling — your choice.

Why

A real reviewer is the gold standard, but they aren't always available the moment you stage a change. CommitBrief gives you a quick, structured read on your diff before another human (or your future self) sees it.

• Local-first. Diffs and review output stay on your machine. The only network egress is to the provider you chose.
• Provider-agnostic. Anthropic, OpenAI, Gemini, or Ollama (no API key needed for local Ollama).
• Cache aware. Re-running on an unchanged diff is essentially free — one disk read, no token spend. --verbose shows what you saved.
• Custom review rules. A repo's COMMITBRIEF.md is sent as the system prompt; per-user OUTPUT.md controls how findings are formatted.

Install

Homebrew (macOS / Linux)

brew install CommitBrief/tap/commitbrief

Scoop (Windows)

scoop bucket add commitbrief https://github.com/CommitBrief/scoop-bucket
scoop install commitbrief

Go

go install github.com/CommitBrief/commitbrief/cmd/commitbrief@latest

GitHub Releases

Pre-built binaries for Linux, macOS, and Windows on amd64 and arm64 are attached to each tagged release at github.com/CommitBrief/commitbrief/releases.

Quick start

# 1. One-time setup: pick a provider, paste your API key, run a ping.
commitbrief setup

# 2. (optional) Write a project-specific review rules file.
commitbrief init

# 3. Stage some changes and review them.
git add path/to/changed.go
commitbrief --staged

commitbrief list prints the full command reference; commitbrief dry-run --staged walks the pipeline without spending tokens.

What you get

Default TTY output is a framed view: a header, a status line, one bordered panel per finding (colored by severity), and a one-line summary footer. Findings are ordered critical → info.

commitbrief v0.6.0 · provider: anthropic/claude-sonnet-4-6 · cache: miss
analyzing 3 files · 42 added · 11 removed · COMMITBRIEF.md loaded

┌─ CRITICAL ─ internal/auth/session.go:142 ──────────────────────────────────┐
│ SQL fragment built from request input                                       │
│                                                                             │
│ String concatenation feeds db.Query() directly, bypassing the prepared      │
│ statement path used elsewhere in this package.                              │
│                                                                             │
│   - q := "SELECT * FROM sessions WHERE token = '" + tok + "'"               │
│   + q := "SELECT * FROM sessions WHERE token = $1"                          │
│     rows, err := db.Query(ctx, q, tok)                                      │
└─────────────────────────────────────────────────────────────────────────────┘

┌─ HIGH ─ internal/db/migrate.go:73 ─────────────────────────────────────────┐
│ NOT NULL column added without a default                                     │
│                                                                             │
│ The new column has no DEFAULT, so the migration will fail on any table     │
│ that already has rows. Either backfill in a prior migration or add a       │
│ DEFAULT before the constraint.                                              │
└─────────────────────────────────────────────────────────────────────────────┘

┌─ LOW ─ internal/api/handler.go:201 ────────────────────────────────────────┐
│ Wrapped error duplicated in message                                         │
│                                                                             │
│ The format string already contains "%w"; the prefix repeats the wrapped    │
│ error verbatim, producing "auth failed: auth failed: …" in logs.           │
└─────────────────────────────────────────────────────────────────────────────┘

✓ Done in 4.2s · 3 findings · 8421 tokens · Cost: $0.0319

Five severity levels — critical, high, medium, low, info — colored red/orange/yellow/blue/grey. info items are always shown; suppress them with a user-side OUTPUT.md template (see Configuration).

Re-run the same command on the same diff and the footer switches to Saved: $0.0319 — a local cache hit, no provider round-trip. --json emits the raw findings (documented schema), --markdown runs your OUTPUT.md template against the findings and writes plain text suitable for >> review.md.

Command surface

# Review scopes
commitbrief                                # = --staged (default scope)
commitbrief --unstaged                     # working-tree changes
commitbrief diff HEAD                      # working tree vs HEAD (git-diff passthrough)
commitbrief diff HEAD~3 HEAD               # the last three commits
commitbrief diff main feature              # one branch vs another
commitbrief diff main...feature            # three-dot PR-style range

# Narrow any scope with repeatable path filters
commitbrief --unstaged --file app/Http/Controllers/API.php --file routes/web.php
commitbrief --unstaged --dir database/seeder --dir app/Models
commitbrief diff HEAD~3 HEAD --dir docs

# Setup and rules
commitbrief setup [--local]                # provider + API key wizard
commitbrief providers list|use|test        # switch active provider without re-running setup
commitbrief config show|get|set            # inspect / tweak the merged YAML config
commitbrief init                           # write COMMITBRIEF.md + OUTPUT.md template
commitbrief compress [--level=balanced]    # shrink COMMITBRIEF.md
commitbrief doctor                         # health-check the pipeline
commitbrief install-hook [--hook=...]      # install a git hook that runs commitbrief
commitbrief dry-run                        # pipeline preview; no API call
commitbrief list                           # command reference

# Cache maintenance
commitbrief cache clear                    # wipe every cached LLM response for this repo
commitbrief cache prune [flags]            # bounded cleanup; defaults --keep-last 500 --older-than 7d

Global flags include --json, --markdown, --output <file>, --copy, --compact, --no-cache, --fail-on=<sev>, -f/--file (repeatable), -d/--dir (repeatable), --yes, --verbose, --quiet, --lang, --provider, --model, --color. See commitbrief --help.

Providers and pricing

Adding a provider is one new package under internal/provider/<name>/.

Configuration

Two-tier YAML config with field-level merge:

• User: ~/.commitbrief/config.yml — defaults that apply everywhere
• Repo: ./.commitbrief/config.yml — overrides for this repo (gitignored by default; run commitbrief setup --local to write it)

Plus environment variables for credentials (ANTHROPIC_API_KEY, OPENAI_API_KEY, GEMINI_API_KEY) and CLI flags for one-off overrides (--provider gemini --model gemini-2.5-flash).

# ~/.commitbrief/config.yml
version: 1
provider: anthropic                # default provider
providers:
  anthropic:
    model: claude-opus-4-7
  openai:
    model: gpt-4o
  ollama:
    model: qwen2.5-coder:14b
    base_url: http://localhost:11434
output:
  lang: en                         # CLI strings + review language
  stream: true
  color: auto                      # auto | always | never
cache:
  enabled: true
  ttl_days: 7

Review content lives in two files:

• COMMITBRIEF.md at the repo root — team-shared review rules, perspectives, project context. Sent to the LLM as the system prompt. Committed to git.
• .commitbrief/OUTPUT.md (or ~/.commitbrief/OUTPUT.md) — per-user Go text/template applied locally to the findings for --markdown and --output <file>.md. Never sent to the LLM. The template has access to .Findings (typed []Finding{Severity, File, Line, Title, Description, Language, Snippet}) plus helpers like groupBySeverity, upper, countFiles. Gitignored.

commitbrief init writes both templates from the embedded defaults.

Filtering

Three layers, applied in order. Later layers win, so a !pattern in .commitbriefignore can revert a built-in exclusion:

1. Built-in defaults — binaries, lock files, vendor/**, node_modules/**, generated code, build artifacts, IDE/OS noise.
2. .commitbriefignore at the repo root — gitignore syntax, team-shared.
3. COMMITBRIEF.md semantic filter — natural-language rules the LLM applies to whatever survives the first two layers.

commitbrief dry-run --staged reports how many files each layer removed.

Building from source

Requires Go 1.25+.

git clone https://github.com/CommitBrief/commitbrief
cd commitbrief
make build         # → ./commitbrief (ldflags inject version/commit/date)
make test          # unit + integration tests (live providers skipped)
make lint          # golangci-lint v2
make smoke         # end-to-end pipeline check; no API key needed
make bench         # diff pipeline + cache hit benchmarks
make manpage       # regenerate man/*.1 from cobra
make test-live     # provider tests against real APIs (keys required)
make license-check # GPL-3.0 compatibility audit

make help lists everything.

FAQ

Does CommitBrief replace human review? No. It's a first pass — a fast sanity check before a teammate (or your future self) looks. The default rules deliberately target low-risk, high-signal stuff: obvious bugs, missing nil checks, accidental secrets. Treat output as a checklist to skim, not a verdict.

Where does my code go? Diffs leave your machine only when sent to the provider you picked. Anthropic, OpenAI, and Gemini get the diff + your COMMITBRIEF.md over HTTPS to their official endpoints. Ollama is local-only; nothing leaves the host. Review output is rendered locally and cached under ./.commitbrief/cache/ — never uploaded.

Will it break my workflow if the LLM provider is down? The CLI fails loudly and exits non-zero. There's no degraded mode that silently skips review. Use commitbrief dry-run to test the pipeline end-to-end without an API call.

How do I exclude generated code or vendored files? Built-in defaults already skip vendor/**, node_modules/**, lock files, binaries, and most generated artifacts. Drop a .commitbriefignore at the repo root for project-specific rules (gitignore syntax, supports !negation to revert a built-in). commitbrief dry-run --staged reports how many files each layer removed.

When does the cache invalidate? The cache key is a SHA-256 of `diff + system prompt + provider + model

• lang + schema version. Change any of those and you get a fresh review. Default TTL is 7 days; configurable via cache.ttl_days`.

Can I run it in CI? The primary target is the developer's terminal, but the CI-friendly pieces are in place: --fail-on=<severity> (or --fail-on=any) returns a non-zero exit code when a finding meets or exceeds the threshold, --json emits the structured-findings document machine- readably, and commitbrief install-hook scaffolds a pre-commit / commit-msg / pre-push hook locally. A dedicated GitHub Action wrapper is still on the v1.x roadmap; for now drive the binary directly from your workflow.

Why GPL-3.0? The CLI is end-user software, and copyleft keeps forks and redistributions open. New dependencies must stay GPL-compatible (MIT/Apache-2.0/BSD/ISC/MPL-2.0/LGPL-3.0+ are fine); make license-check enforces it.

License

GPL-3.0-or-later. Provider SDK dependencies are Apache-2.0 or MIT; the full audit is make license-check.

Contributing

See CONTRIBUTING.md for the project-specific build and test flow, and the org-wide CONTRIBUTING guide for inbound-equals-outbound licensing and PR conventions.

Bug reports and questions are welcome in Issues and Discussions.