I like ADK, it's lower level and more general, so there is a bit you have to do to get a "claw" like experience (not that much) and you get (1) a common framework you can use for other things (2) a lot more places to plug in (3) four SDKs to choose from (ts, go, py, java... so far)

It's a lot more work to build a Copilot alternative (ide integration, cli). I've done a lot of that with adk-go, https://github.com/hofstadter-io/hof