Plannotator

Plannotator is a free, open-source review surface for AI coding agents like Claude Code, Codex, and others. It runs locally in your browser and integrates directly with agent workflows through hooks and commands. When an agent proposes a plan or finishes writing code, the work opens for you to annotate, comment, and send feedback back to the agent for refinement.

The tool supports reviewing markdown documents, code diffs from Git and other version control systems, and HTML artifacts. You can comment on changes, suggest code improvements, and use built-in AI to ask questions about reviewed content. Plannotator also offers a terminal version called Herdr Annotate for reviewing agent replies within terminal workflows.