The Harness, As Feynman Might Have Taught It
An imagined Feynman lecture on the dumbest, most important program in AI: the loop around the model. Play the harness by hand, take one apart, then build a real one on a single page of Python.
Agents: An LLM in a Loop
An agent is an LLM in a loop: call a tool, read the result, decide, repeat. Watch one fix a bug, then see why long runs break, overspend and need guardrails.