A reminder that, while this is pretty neat and also probably offers a lot of convenient tooling for GCloud resources already built, an "agent" is simply an LLM call in a loop, each call presenting some number of available tools. If you're building your first agent, I'd recommend coding to an LLM API (probably the OpenAI Responses API, which is sort of a lingua franca of LLMs now) directly.

This is one of those cases where it's really helpful to code, at least once, at one layer of abstraction below the one that seems most natural to you.