Function / tool calling is actually super simple. I'd honestly recommend either doing it through a single LLM provider (e.g., OpenAI or Gemini) without a hard framework first, and then moving to one of the simpler frameworks if you feel the need to (e.g., LangChain). Frameworks like LangGraph and others can get really complicated really quickly.
Check the OpenAI REST API reference. Most engines implement that and you can see how tool calls work. It’s just a matter of understanding the responses they give you, how to put them in the messages history and how to invoke a tool when the LLM asks for it.
There may be other reasons to use ai sdk, but I'd highly recommend starting with a simple loop + port most relevant tools from Claude Code before using any framework.
Nice, do share a link, would love to check out your agent!
for context, i want to build a claude code like agent in a WYSIWYG markdown app. that's how i stumbled on your blog post :)