Chapter 1: Finding a Stable Abstraction
The first question in agent engineering isn't "how do I build one" — it's "what is an agent, exactly?" Until that question has an answer, frameworks can only unify surface-level workflows, and the parts just sit in a pile.
This chapter runs from "a tool-using animal" to a more stable abstraction. First, why frameworks can't bear weight when no stable abstraction exists. Then, why the popular definition — a tool-using animal — explains what an agent can do but not who it is. Finally, the skill: a concrete unit of capability that snaps the whole picture into place.