Group of 2 Under the hood
SDK init handshake now reports which skills and plugins are in use.
The init frame handshake now carries skills and plugins fields in addition to what it already sent. For a remote/cloud session, the client-side hook that processes the worker's init frame now captures skills and plugins as well as the previously-captured slash_commands and model, presumably to surface available skills and plugins for that session's UI.
In the stream-json/Agent SDK init handshake, the same skills and plugins arrays are now parsed from the init frame alongside the existing tools field, with an error logged if either is malformed, presumably surfacing enabled skills and plugins to SDK consumers.