Tulip

Tulip is an open-source CLI from VirtusLab that explains GitHub pull requests and GitLab merge requests by categorizing and prioritizing the changes and presenting them on a web page as prose, diagrams, and code. It drives a headless agent CLI (Claude Code by default, or Cursor's agent or OpenAI's codex) for the analysis, so a logged-in CLI is used rather than an API key. According to the README, it is part of Visdom, VirtusLab's AI-native SDLC platform.

What It Is

Tulip is a code-review aid. Given a PR or MR URL, it produces a self-contained HTML explanation that is top-down: a high-level overview first, then the code. Every code change appears somewhere in the explanation, while changes are grouped by concern and rated by attention level (Read closely / Read through / Skim) so reviewers can focus on algorithms, design choices, and core functionality.

How the Analysis Pipeline Works

Tulip fetches the PR (title, description, diff) via the gh CLI or GitHub API, or via the GitLab API for merge requests, and checks out the head revision. It then runs several LLM passes, each with a model sized to the job: categorize changes into groups, split large multi-concern changes, classify every change to groups as production or test code, and explain each group. Explanations open with an orienting diagram (dependency, data flow, class, state, ER, or sequence) and then drill into each change. Review passes check that referenced snippets appear and diagrams render. The output is a page with light/dark theme, a foldable table of contents, syntax-highlighted side-by-side diffs, and attention badges.

Setup and Usage

Tulip requires Node.js LTS (>= 24) and a logged-in agent CLI on PATH. It installs from npm and runs as tulip <PR URL>, with flags such as --diff-threshold, --verbose, --serve, --no-open, and --agent. The chosen agent is saved in a config file. Private repositories, GitHub Enterprise Server, and self-hosted GitLab are supported with appropriate credentials. The --serve mode hosts the page locally and lets reviewers post notes as PR comments per category; it is GitHub-only and needs an authenticated gh CLI.