One last distinction, and it is the reason agents make this chapter matter more.

Simple versus easy

Easy means close at hand or familiar. Simple means not tangled together. The two are independent: a tool can be easy to start with and leave you a knot. Rich Hickey drew this line in a 2011 talk.

Agents make nearly everything easy. A working feature is one sentence away, whatever it tangles together. So "easy" has stopped telling you anything, and "simple" is what is left to judge. You still have to ask for it.

Say it to your agent

“This works, but caching and pricing are tangled: I can't change one without reading the other. Separate them so the price function knows nothing about the cache. The test is whether each can be changed without opening the other.”

Not to be confused with Fewer things

Simple doesn't mean few. Hickey separates counting things from interleaving them, so ten separate parts can be simpler than three that are tangled.

Where you see it

Hickey's Simple Made Easy, Strange Loop 2011. From the talk's abstract: "We should be simplifying the problem domain, and creating solutions by composing simple parts. Instead, we endure complexity, and pride ourselves in our ability to manage it." The definitions above are paraphrased from a community transcript. Kent Beck, working with agents in 2025, was "still working on getting the genie to care as much as I do about simplicity."

Simple versus easy

Before the agent

The agent

The harness

Everything it can get wrong

The operator

The workshop