ProtoVibing

02 · PLAN

Find the signal in the noise.

Scope the smallest thing this loop can actually validate.

WHAT THIS PHASE PRODUCES

You leave with

  • A market context note: who exists, what they’re doing, what nobody’s doing yet
  • A P0 scope you can actually validate this loop
  • A visual direction tight enough to brief a prototype

THE MENTAL MODEL

How to think about this phase

Plan is where most founders over-spend. They mistake the phase for “write the PRD”, fan out into a six-week research project, and arrive at Test with a roadmap they’re too invested in to throw away.

The point of Plan is not comprehensiveness; it is sufficiency. You need enough market context to know which trapdoors you’re walking past, and enough scope discipline to leave with a P0 you can build and test inside one loop.

If you find yourself adding features to the P0 because they’re “easy”, stop. Easy is a vibe-coding trap. The P0 must isolate one variable: the single thing your hypothesis is actually about. Anything else is noise that will make the test result un-attributable.

Visual direction belongs here too, not as polished design but as the shared mental image that lets you brief a prototype without re-explaining the bet five times. A wireframe sketch and three reference URLs beat a Figma file you’ll throw away.

COMMON TRAPS

What goes wrong in this phase

  • Building a feature comparison table. Founders always do this. It produces nothing actionable.
  • Scoping a P0 that tests three things at once. Whatever the result, you won’t know which variable moved it.
  • Treating Plan as the place to lock the roadmap. The roadmap belongs after a loop closes, not before.
  • Rationalising scope creep with “while we’re in there”. Every extra surface adds a confound.

WHAT GOOD LOOKS LIKE

A worked example

SETUP

From the Idea example: the “first-draft PRD” bet for Series-B PMs.

OUTPUT

After Plan: “P0 = a single web form where a PM pastes a problem statement and receives, within 60 seconds, a structured outline plus the specific clarifying questions still missing from their statement. No saving, no auth, no team features. We test the trade: would they actually paste their next real problem in.”

Practicing this phase? Run the full loop on the platform with your team.