18 min · up to 80 XP

Agents and tools

How AI reaches beyond the chat box into real systems.

A rainy Tuesday, and Sam catches herself doing something odd. In one window: her coding agent, which has been running BookNook's tests all evening. In the other: a plain chat tab, where she's just pasted a function and typed "run this and tell me the output."

Roughly the same kind of model behind both windows. So before the chat tab answers, what is it about to do?

Predict the response

Sam pastes a short function into a plain chat tab, no agent, no project, just chat, and asks it to run the code. Predict what actually happens.

Here's my addTip function: [pastes code]. Run it with addTip(100, 10) and tell me the output.

What do you think the AI will do?

The answer is tools. A tool is real software that sits outside the model, a terminal, a file reader, a web fetcher. The model still can't touch any of it directly. What it can do is emit a structured request: please run the tests. The tool actually executes, and whatever happened, output, errors, file contents, gets pasted back into the context window, the only place a model can ever read from.

Here's one round trip, slowed right down.

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