How to annotate Claude Code and Codex plans in the browser with Plannotator

Plannotator is a local tool that opens your coding agent's plans, documents and code changes in the browser so you can annotate them and send the feedback straight back to the agent. Once installed, the review page opens automatically whenever Claude Code produces a plan in plan mode.

1. Run the installer (macOS, Linux, WSL). It installs the plannotator binary, detects your agents, and adds hooks, skills and slash commands.

curl -fsSL https://plannotator.ai/install.sh | bash

1. In Claude Code, install the plugin and restart Claude Code. Codex needs nothing more: the installer turns on plan review through Codex's experimental Stop hook.

/plugin marketplace add backnotprop/plannotator
/plugin install plannotator@plannotator

1. Common commands:

/plannotator-review                  # review uncommitted changes
/plannotator-review <github-pr-url>  # review a GitHub PR
/plannotator-annotate README.md      # annotate a markdown file
/plannotator-last                    # annotate the agent's last message

In Codex, use the $plannotator-review, $plannotator-annotate and $plannotator-last skills or !plannotator review instead of slash commands.

On Claude Code 2.1.287 or newer, Claude ends its turn instead of waiting during a review, and your decision arrives later as a message. Set PLANNOTATOR_CLAUDE_MOD=0 to go back to the waiting flow. It collects no usage telemetry and keeps plans and annotations local, but each review page checks GitHub for the latest release when it loads. Licensed under Apache-2.0.