What an agent can actually do to an Android project
Across: what the agent is doing. Down: where it happens, from the screen all the way to the source. Each cell says what that lets the agent do. Open a filled cell to see the tools. Open an empty one to see what is missing.
This is not your choice. compose-preview-scanner cannot use a device and maestro cannot run without one. The tools that need a device do not care whether it is an emulator or the phone on your desk.
This line is also where the cost sits. jvm tools run in seconds, while device tools have to boot, install and drive something. Speed follows this line rather than the columns: lint and unit tests both sit in Assert, and they are the two fastest checks here.
The full app, or a small playground app with one feature: one screen, no login, no navigation, no backend. Any device tool can be pointed at either, and pointing it at the playground is the cheapest decision in the grid.