Tool calling is underrated

Everyone talks about LLM capabilities as if generation quality is what matters. It is not. The real power is orchestration, and tool calling is the mechanism.

A well-designed tool-calling agent can coordinate complex workflows by deciding what to do, calling the right tools, interpreting results, and adapting based on what it learns. The generation quality matters much less than the tool design.

Good tool design means clear contracts. What does this tool do? What inputs does it need? What outputs does it produce? What errors can it return? The clearer these boundaries, the better the agent performs.

Good tool design means appropriate granularity. Tools that are too broad become unpredictable. Tools that are too narrow require too many calls. Finding the right level of abstraction is an art.

Good tool design means helpful error messages. When a tool fails, the agent needs to understand why. Errors like operation failed help no one. Errors like rate limit exceeded, retry after 60 seconds let the agent adapt.

I spend more time designing tool interfaces than writing prompts. The tools define what the agent can do. The prompts just guide how it chooses between them. Get the tools right and the prompts almost write themselves.