How do I build a simple AI agent with function calling?
Define your tools as JSON schemas, then let the model decide when to call them. Start simple: one tool for search, one for calculation. The model returns a function call instead of text, you execute it, feed results back. Loop until done.
When to use this
When building bots that need to take actions in the real world, like booking or searching.
When to skip this
For simple Q&A where the model's knowledge is sufficient.
Advanced OpenAI API or Claude API with tool use