Plannotator
Visually annotate and review coding-agent plans and diffs, then send feedback back to the agent.
Updated
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Use cases
About Plannotator
Plannotator is listed in our coding category and is aimed at builders. Visually annotate and review coding-agent plans and diffs, then send feedback back to the agent. Pricing, as the maker states it: Open source. Maturity: Mature. We last checked the official link on 2026-10-16.
What is Plannotator?
Plannotator is a local, browser-based review surface for AI coding agents, including Claude Code, Codex, Copilot CLI, Gemini CLI, OpenCode, Kiro, Droid, Amp and Pi.
It plugs into your agent through hooks and commands. When the agent proposes a plan or HTML, or finishes writing code, the work opens in your browser so you can mark it up, comment on diffs or PRs, suggest code and send the feedback straight back to the agent.
Sources: the official README and our directory listing, checked 2026-10-18. Official site: plannotator.ai.
Who is Plannotator for?
Developers who want to review and annotate agent plans and diffs visually before the agent continues.
Plannotator at a glance
- Open source: Yes (Apache License 2.0)
- GitHub: backnotprop/plannotator · 9,556 stars (as of Oct 21, 2026)
Key features
- Annotate plans, specs, Markdown and HTML
- Review local diffs and remote PRs
- Feedback goes straight back to the agent
- Works with many coding agents
Plannotator FAQ
What is Plannotator?
Plannotator is a local, browser-based review surface for AI coding agents, including Claude Code, Codex, Copilot CLI, Gemini CLI, OpenCode, Kiro, Droid, Amp and Pi.
Who is Plannotator for?
Developers who want to review and annotate agent plans and diffs visually before the agent continues.
Is Plannotator free?
Plannotator's pricing, as the maker states it: Open source. Open-source tools are free to use, though you may still pay for model API usage or a hosted plan. Check the official site for current plans.
Is Plannotator open source?
Yes. Plannotator is released under the Apache License 2.0, according to its GitHub repository.
What are alternatives to Plannotator?
Similar tools include Open Code Review, Emdash, Shippie, OpenSumi, cubic and KaneAI.
Plannotator ratings and reviews
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