Bits of this tutorial feel a little bit out-dated. The appendix on function calling for example - https://github.com/anthropics/courses/blob/master/prompt_eng... - shows how to implement function calling from scratch using XML-style tags - but Claude's API has had JSON schema-based function calling for a few months now: https://docs.anthropic.com/en/docs/build-with-claude/tool-us...

Oh, never mind - they have an entire separate course about tool use via the API here: https://github.com/anthropics/courses/blob/master/tool_use/0...

So they're using tools in that appendix purely to demonstrate how sophisticated you can get with raw prompting.