Last square: turn "how you do it" into "anyone can do it"
In the first five squares you built an Agent that can actually work — but all the judgment still lives in your head. This square writes that down as rules. Once they stand, a different person, a different project, a different model — the same system still runs. That's engineering, not craft.
This chapter's four-step flow (restate, PRD, confirm, code) solves two faces of the same problem: the AI misunderstood the requirement and charged ahead anyway, and by the time you notice it has already changed twenty files. The breakpoint has to sit before it starts working. Any correction after that is rework.
Same requirement, two ways to hand it over
AI restates the requirement
In its own words, what it is supposed to do — if it's off, you see it on the spot
Write a PRD
The plan, the boundaries, what not to do — in black and white
Wait for your confirm
Human gate: no nod, no coding
Start coding
Only now does it start. What it writes is the thing you already confirmed
You don't have to write rules from scratch
The xs_vibe_rules this chapter unpacks is something you can Fork directly. Just don't copy the whole set. A rule is valuable because a real crash sits behind it. A crash you never had — paste the rule and you still won't keep it. The right move: pick three to five rules from the pits you hit in the first five squares, then borrow from the repo the ones where you understand the "why."
This Chapter's Hands-on Checklist
0 / 3 done
Write your first Rule
15 min EveryoneFrom the first five squares, pick the pit that hurt the most and write it as a rule. Use the format this chapter taught: first the why (that crash), then the how (a concrete instruction). If format drift burned you at M1, the rule is "every output must match template XX; if it isn't in the materials, write 'not mentioned'."
What counts as done
Walk a real requirement through the four-step flow
1 hour Anyone who works with AINext real requirement, don't toss it straight to the AI. First ask it to restate; if the restate is off, correct it. Then have it write a one-page mini PRD. Only after you confirm do you let it go. Feel the whole thing: after you move the breakpoint forward, how much smaller is the gap between the result and what you expected.
What counts as done
Export the Build Log, shape it into spec v1
Half a day Anyone walking the full trackGo back to the Build Log, fill in all six milestones, export Markdown. Then the last step: shape it into your own AI collaboration spec: how you set requirements (M0), how you write prompts (M1), how you wire tools (M2), how you evaluate (M3), how you run long (M4), how the flow goes (M5). Send it to a colleague. See if they can build something similar from it.