AI tool comparison
Ferretlog vs React Doctor
Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.
Developer Tools
Ferretlog
git log for your Claude Code agent runs — local, zero dependencies
50%
Panel ship
—
Community
Free
Entry
Ferretlog is a zero-dependency pure Python CLI that treats your Claude Code session logs like a git repository. It parses the raw JSONL logs in `~/.claude/projects/` and gives you git-style history browsing, diff between runs, per-tool-call breakdowns, and cost/token stats — entirely locally, with no network calls and no configuration required. If you've been using Claude Code heavily, you've likely experienced the frustration of losing track of what changed across sessions, what tools were called how many times, and how much each session actually cost across sub-agent calls. Ferretlog makes that history explorable and comparable the same way `git log` makes code history explorable. This is an indie solo project from Eitan Lebras, submitted as a Show HN. It's genuinely useful as a power-user tool for anyone doing serious Claude Code work, especially those managing multi-session agent pipelines where debugging "what did the agent do last time?" is a real pain. The zero-dependency, local-only design means there's no trust surface and no setup friction.
Developer Tools
React Doctor
Catch every anti-pattern your AI agent baked into your React app
75%
Panel ship
—
Community
Paid
Entry
React Doctor is a one-command static analysis tool that scans your React codebase and outputs a health score from 0 to 100 alongside a detailed diagnostic report. Run `npx react-doctor@latest .` and it identifies anti-patterns across six dimensions: state & effects, performance, architecture, security, accessibility, and dead code. It auto-detects your framework (Next.js, Vite, React Native) and React version, adjusting rules accordingly. The tool was built by Million.co—the team behind the Million.js performance library—and is clearly aimed at the post-AI-coding era. Its killer feature might be the "agent instruction installation" mode: it teaches Claude Code, Cursor, and other coding agents the project's quality rules, so future agent-written code conforms to them before React Doctor even runs. It also integrates with GitHub Actions and can post PR comments with health score diffs, making it easy to catch regressions before merge. With 8.7K stars and one of today's fastest-growing GitHub repos, the timing is perfect. Developers are increasingly shipping agent-written React code they didn't review line by line, and React Doctor fills the gap. It's MIT-licensed, requires no config to get started, and the CI integration takes about five minutes to set up.
Reviewer scorecard
“If you run Claude Code daily, you need this immediately. Being able to diff two sessions like git commits and see exactly which tools fired and what they cost is something that should have existed from day one. Zero-dependency Python means it just works.”
“The GitHub Actions integration with PR health score diffs is the feature I didn't know I needed. Installing it took three minutes and immediately flagged three useEffect anti-patterns Cursor introduced last week.”
“This is a niche tool for a niche user (heavy Claude Code power users) and the session log format Anthropic uses is undocumented and could change at any update. Tying workflows to internal log parsing is fragile infrastructure — treat it as a convenience, not a dependency.”
“Static analysis for React isn't new—ESLint with react-hooks/exhaustive-deps, Biome, and others already catch most of these patterns. The 'health score' framing may encourage false confidence if teams focus on the number rather than the individual findings.”
“Agent observability tooling built by the community, not the vendor, is how this ecosystem will mature. Ferretlog is primitive but it points at a real gap: we need git-style versioning and auditability for agent sessions, not just for code.”
“Teaching agents the rules upfront rather than fixing their output afterward is the right architectural direction. As agent-written code becomes the norm, tools that close the feedback loop at the prompt level will be as important as compilers.”
“Terminal-only, Claude Code-specific, no visuals — this tool exists entirely outside my workflow. The underlying insight (session replay and cost tracking) is useful, but it needs a UI before it reaches anyone outside the developer community.”
“For designer-developers who use Cursor or v0 to prototype quickly, this is a sanity check that doesn't require deep React expertise. A green health score before shipping is a meaningful confidence boost.”
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