Prototype-First Workflow
Prototypes exist to kill bad ideas cheaply. A prototype that can only succeed is a demo — this skill plans the one that can fail.
Verification gates (defined first; output is blocked until all pass)
- G1 — Kill hypothesis named: the plan states what the prototype must DISPROVE — a falsifiable claim with a numeric threshold set before the run ("recruiters discard >80% of senior-candidate drafts"). Demonstrate-only plans ("show the drafts are useful") fail the gate.
- G2 — Minimum lethal build: every component of the plan is justified by the kill test. Scope that serves the demo but not the test is cut; if a cheaper build (Wizard-of-Oz, concierge, template sidecar) can kill the hypothesis, the plan must use it or say why not.
- G3 — Consequences pre-committed: thresholds carry their basis, measurement is defined (what's logged, window, N — from stated context only), and both branches exist: if killed → what, if survived → what. No invented user counts or benchmark thresholds.
Steps
- Extract the fight. What is the team actually arguing about? That disagreement is the kill hypothesis's home — the fixture risk ("recruiters won't trust AI drafts with senior candidates") converts directly. If nothing is contested, ask what would make the team abandon the idea; if truly nothing would, say the prototype is theater and stop.
- Write the kill hypothesis: falsifiable, thresholded, time-boxed. Use the team's own claims as bars ("saves 30 min/day" → the prototype must clear it). The threshold's basis is stated — team claim, prior data, or an explicit stake-in-the-ground labeled as such.
- Design the minimum lethal build. Start from the cheapest tier — paper/concierge → Wizard-of-Oz → sidecar/stub → flagged feature — and take the first tier that can genuinely kill the hypothesis. Justify each component against the test; name what was deliberately cut.
- Define measurement: metrics (edit distance, discard rate, time-on-task), instrumentation, run window, and who participates — drawn from the stated context (e.g. 2 of 5 partner agencies), never invented cohorts.
- Pre-commit both branches. Killed → the named decision (drop, reshape, retest a narrower claim). Survived → the next-larger test or the build ticket, with what changes in confidence. Write these BEFORE the run so results can't be renegotiated.
- Gate pass. Kill hypothesis + threshold present (G1), every component test-justified (G2), measurement + branches from stated context (G3). Fix and re-run; maximum 2 repair loops, then report the failure.
Output format
PROTOTYPE PLAN: AI-suggested replies (recruiting CRM)
KILL HYPOTHESIS (must disprove): "recruiters edit-beyond-recognition or discard >80%
of drafts on senior-candidate emails" — threshold basis: team's trust concern, stated
BUILD (minimum lethal): LLM sidecar drafting from 5 templates; no CRM integration;
2 of 5 partner agencies; 2 weeks. CUT: UI polish, all-role coverage, auto-send (serve demo, not test)
MEASURE: per-draft accept/edit/discard + edit distance + self-reported time, logged daily
IF KILLED: drop senior-candidate scope; retest junior-only claim before any build
IF SURVIVED: flagged pilot at all 5 agencies with the 30-min/day bar as the next kill line
GATE CHECK: G1 pass (falsifiable + threshold) · G2 pass (each component justified, cuts named) · G3 pass
Hard rules
- No plan ships without its kill hypothesis. "What must this disprove?" has an answer or the prototype is a demo — say which.
- The team's own claims become the thresholds. A prototype that measures against softer bars than the pitch is rigged.
- Never invent cohorts, baselines, or industry thresholds. Participants and bars come from the stated context or are labeled stakes-in-the-ground.
- Both branches are written before the run. A plan with only a success path has already decided the result.
Limitations
- The plan is a test design; running it, recruiting the users, and instrumenting the build are execution work.
- A survived kill hypothesis reduces one risk — it doesn't validate the feature; the plan says what the next test is, not that the idea is proven.
- Cheap-tier builds (Wizard-of-Oz) test desirability and behavior, not feasibility at scale — feasibility hypotheses need the sidecar tier or above, and the plan flags when that's the real question.
- Threshold choices with no prior data are labeled stakes-in-the-ground; they anchor honestly but aren't derived.
1---2name: prototype-first-workflow3description: Build-stage skill: turns a feature idea into the smallest testable prototype plan — built around what the prototype must disprove, not what it should demonstrate. Use when the user wants to test before building — 'plan the smallest prototype', 'how do we prototype this before committing', 'design the spike', 'fastest way to test if this works' — or when /pm routes such a request here. Do NOT use to execute the build, to make the build/kill call itself (ai-feature-go-no-go), to map assumptions without a test plan (assumption-mapper — its riskiest assumption is this skill's input), or for definitions of prototyping methods.4---56# Prototype-First Workflow78Prototypes exist to kill bad ideas cheaply. A prototype that can only succeed is a demo — this skill plans the one that can fail.910## Verification gates (defined first; output is blocked until all pass)1112- **G1 — Kill hypothesis named:** the plan states what the prototype must DISPROVE — a falsifiable claim with a numeric threshold set before the run ("recruiters discard >80% of senior-candidate drafts"). Demonstrate-only plans ("show the drafts are useful") fail the gate.13- **G2 — Minimum lethal build:** every component of the plan is justified by the kill test. Scope that serves the demo but not the test is cut; if a cheaper build (Wizard-of-Oz, concierge, template sidecar) can kill the hypothesis, the plan must use it or say why not.14- **G3 — Consequences pre-committed:** thresholds carry their basis, measurement is defined (what's logged, window, N — from stated context only), and both branches exist: if killed → what, if survived → what. No invented user counts or benchmark thresholds.1516## Steps17181. **Extract the fight.** What is the team actually arguing about? That disagreement is the kill hypothesis's home — the fixture risk ("recruiters won't trust AI drafts with senior candidates") converts directly. If nothing is contested, ask what would make the team abandon the idea; if truly nothing would, say the prototype is theater and stop.192. **Write the kill hypothesis:** falsifiable, thresholded, time-boxed. Use the team's own claims as bars ("saves 30 min/day" → the prototype must clear it). The threshold's basis is stated — team claim, prior data, or an explicit stake-in-the-ground labeled as such.203. **Design the minimum lethal build.** Start from the cheapest tier — paper/concierge → Wizard-of-Oz → sidecar/stub → flagged feature — and take the first tier that can genuinely kill the hypothesis. Justify each component against the test; name what was deliberately cut.214. **Define measurement:** metrics (edit distance, discard rate, time-on-task), instrumentation, run window, and who participates — drawn from the stated context (e.g. 2 of 5 partner agencies), never invented cohorts.225. **Pre-commit both branches.** Killed → the named decision (drop, reshape, retest a narrower claim). Survived → the next-larger test or the build ticket, with what changes in confidence. Write these BEFORE the run so results can't be renegotiated.236. **Gate pass.** Kill hypothesis + threshold present (G1), every component test-justified (G2), measurement + branches from stated context (G3). Fix and re-run; maximum 2 repair loops, then report the failure.2425## Output format2627```28PROTOTYPE PLAN: AI-suggested replies (recruiting CRM)29KILL HYPOTHESIS (must disprove): "recruiters edit-beyond-recognition or discard >80%30of drafts on senior-candidate emails" — threshold basis: team's trust concern, stated31BUILD (minimum lethal): LLM sidecar drafting from 5 templates; no CRM integration;322 of 5 partner agencies; 2 weeks. CUT: UI polish, all-role coverage, auto-send (serve demo, not test)33MEASURE: per-draft accept/edit/discard + edit distance + self-reported time, logged daily34IF KILLED: drop senior-candidate scope; retest junior-only claim before any build35IF SURVIVED: flagged pilot at all 5 agencies with the 30-min/day bar as the next kill line36GATE CHECK: G1 pass (falsifiable + threshold) · G2 pass (each component justified, cuts named) · G3 pass37```3839## Hard rules40411. No plan ships without its kill hypothesis. "What must this disprove?" has an answer or the prototype is a demo — say which.422. The team's own claims become the thresholds. A prototype that measures against softer bars than the pitch is rigged.433. Never invent cohorts, baselines, or industry thresholds. Participants and bars come from the stated context or are labeled stakes-in-the-ground.444. Both branches are written before the run. A plan with only a success path has already decided the result.4546## Limitations4748- The plan is a test design; running it, recruiting the users, and instrumenting the build are execution work.49- A survived kill hypothesis reduces one risk — it doesn't validate the feature; the plan says what the next test is, not that the idea is proven.50- Cheap-tier builds (Wizard-of-Oz) test desirability and behavior, not feasibility at scale — feasibility hypotheses need the sidecar tier or above, and the plan flags when that's the real question.51- Threshold choices with no prior data are labeled stakes-in-the-ground; they anchor honestly but aren't derived.
Abhillashjadhav