Greenbelt

Greenbelt 🌱

Greenbelt tracks token usage across Claude Code sessions and plants trees whenever your token usage crosses a configurable threshold (1M tokens by default). It uses [Ecologi API](https://ecologi.com/) and runs as a Claude Code hook — no manual steps required after setup.

[Ecologi](https://ecologi.com) is a climate action platform that helps individuals and businesses take measurable, credible action for climate and nature. Fund tree planting from €0.80 (£0.60) per tree. File a feature request if you want to use a different provider.

Get started

Copy and paste the AI prompt:

Clone https://github.com/mikhail-tokarev/greenbelt into the ~/.claude folder and add the hooks as described in README.md

**1. Register the hooks**

Add the following to your Claude Code settings (`~/.claude/settings.json`):

[!IMPORTANT] Replace `/path/to/greenbelt` with the absolute path where you cloned the repo.

{
  "hooks": {
    "SessionStart": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "python3 /path/to/greenbelt/session_hook.py"
          }
        ]
      }
    ],
    "SessionEnd": [
      {
        "hooks": [
          {
            "type": "command",
            "command": "python3 /path/to/greenbelt/session_hook.py"
          }
        ]
      }
    ]
  }
}

**2. Configure Ecologi**

On the first run, Greenbelt creates `~/.claude/greenbelt.toml` automatically:

provider = "ecologi"
threshold = 1_000_000   # plant trees every 1M tokens

[ecologi]
api_key = ""            # get it from https://app.ecologi.com/impact-api

Fill in your [Ecologi API](https://app.ecologi.com/impact-api) key. Adjust `threshold` to control how often trees are planted.

**That's it.** From this point on, Greenbelt runs silently in the background. At the start of each session it shows how many trees you've planted so far.

Uninstall

1. Remove the hooks — delete the SessionStart and `SessionEnd