Basically I wanted to write a book that did not spend the majority of time on training LLM and architecture, as it is just not relevant to the majority of software engineers (either using agent coding tools to help write code, or using the LLM APIs as backend parts of apps you are building).
This Hitchhikers book has many examples of API use as well, but is very "here is a wall of code". Mine is a bit more gentle progressively building up simple examples -- e.g. I show how to write python code to call a tool in a loop. Then show how you can feed back the error and have the LLM update. Then show how you can do that without manually looping through the agents SDK.