Chrome Bridge

CadScript uses the Onshape session already signed in to Chrome. It does not ask for a password or API key.

Prepare The Local Extension

Run:

npx -y onshape-cadscript@0.1.6 setup chrome

CadScript copies the bundled Manifest V3 extension to:

~/Library/Application Support/onshape-cadscript/chrome-extension

It also registers the native messaging host for the extension's stable ID and opens both the directory and chrome://extensions.

1. Enable Developer mode in Chrome.
2. Click Load unpacked.
3. Select the prepared chrome-extension directory.
4. Open an Onshape document and sign in normally.
5. Run cadscript doctor --json.

Loading the unpacked directory is the only manual installation step. The extension ID is fixed by its public manifest key, so users do not copy IDs and native-host permissions do not drift between versions.

Updating

Chrome does not automatically update unpacked extensions. After updating the npm package:

1. Run npx -y onshape-cadscript@latest setup chrome again.
2. Open chrome://extensions.
3. Click Reload on Onshape CadScript Bridge.
4. Run cadscript doctor --json.

For custom extension builds, cadscript bridge install --extension-id <id> remains available as an explicit development override.

Uninstalling

Remove the extension card in chrome://extensions, then run:

cadscript uninstall

That removes the PM2 daemon, its Codex daemon entry, native-host manifests, prepared extension files, and owner-only bridge configuration. It never removes CAD project folders or Onshape documents.

Boundaries

The bridge binds to localhost, requires an owner-only random token, validates a protocol version, limits payloads, and allows only selected Onshape REST paths with GET, POST, and DELETE. It does not provide arbitrary browser evaluation.