App Preview

App Preview finds startable apps in the current thread worktree, runs the detected recipe in a BB terminal, and can open the result in the in-app browser. A Ports list can share a listener over BB Connect or signal it.

Trust and machine effects

This is a full-trust plugin. After you install it:

• Dependency installation. Start can run the detected package manager install (npm / pnpm / yarn / bun / uv / pip / bundle / composer) when that setting is on.
• Repository-script execution. Start runs the detected dev/start recipe from the worktree in a BB terminal. Agents can only start that detected recipe. They cannot pass an arbitrary command. The Preview panel and bb preview start --command may override with a plain argv (no substitutions, quotes, or shell operators).
• Process signaling. Ports can send SIGTERM or SIGKILL to a listener by port or PID. Agent share, unshare, and kill wait for an in-app confirmation that echoes a plugin-issued token. The Ports panel still asks before kill.
• BB Connect exposure. Share publishes a listening port as https://<handle>--<port>.getbb.app. That URL is reachable from other machines and phones while the share exists.

Preview state lives in the plugin SQLite database. It does not call a third-party API or store credentials.

Launch safety (0.2.9)

Start is a working directory plus argv recipe. The worktree path is not interpolated into the shell command string. Nested apps cd -- ./dir so CDPATH cannot redirect them.

Install

The installable package is app/.

bb plugin install git:github.com/hungv47/bb-plugin-app-preview@semver:^0.2.9 --subdirectory app