Prototype

• What is the core question?
• What is the absolute minimum code needed to answer it?
• What can be skipped (error handling, polish, architecture)?

Present this plan to the user before building. Ask for confirmation if scope seems unclear.

Phase 4: Implement

Ask: "May I create the prototype directory at prototypes/[concept-name]/ and begin implementation?"

If yes, create the directory. Every file must begin with:

// PROTOTYPE - NOT FOR PRODUCTION
// Question: [Core question being tested]
// Date: [Current date]

Standards are intentionally relaxed:

• Hardcode values freely
• Use placeholder assets
• Skip error handling
• Use the simplest approach that works
• Copy code rather than importing from production

Run the prototype. Observe behavior. Collect any measurable data (frame times, interaction counts, feel assessments).

Phase 5: Generate Prototype Report

Draft the report:

## Prototype Report: [Concept Name]

### Hypothesis
[What we expected to be true -- the question we set out to answer]

### Approach
[What we built, how long it took, what shortcuts we took]

### Result
[What actually happened -- specific observations, not opinions]

### Metrics
[Any measurable data collected during testing]
- Frame time: [if relevant]
- Feel assessment: [subjective but specific -- "response felt sluggish at
  200ms delay" not "felt bad"]
- Player action counts: [if relevant]
- Iteration count: [how many attempts to get it working]

### Recommendation: [PROCEED / PIVOT / KILL]

[One paragraph explaining the recommendation with evidence]

### If Proceeding
[What needs to change for a production-quality implementation]
- Architecture requirements
- Performance targets
- Scope adjustments from the original design
- Estimated production effort

### If Pivoting
[What alternative direction the results suggest]

### If Killing
[Why this concept does not work and what we should do instead]

### Lessons Learned
[Discoveries that affect other systems or future work]

Ask: "May I write this report to prototypes/[concept-name]/REPORT.md?"

If yes, write the file.

Phase 6: Creative Director Review

Review mode check — apply before spawning CD-PLAYTEST:

• solo → skip. Note: "CD-PLAYTEST skipped — Solo mode." Proceed to Phase 7 summary with the prototyper's recommendation as the final verdict.
• lean → skip (not a PHASE-GATE). Note: "CD-PLAYTEST skipped — Lean mode." Proceed to Phase 7 summary with the prototyper's recommendation as the final verdict.
• full → spawn as normal.

Spawn creative-director via Task using gate CD-PLAYTEST (.claude/docs/director-gates.md).

Pass: the full REPORT.md content, the original design question, game pillars and core fantasy from design/gdd/game-concept.md (if it exists).

The creative director evaluates the prototype result against the game's creative vision and pillars, then confirms, modifies, or overrides the prototyper's PROCEED / PIVOT / KILL recommendation. Their verdict is final. Update the REPORT.md Recommendation section if the creative director's verdict differs from the prototyper's.

Phase 7: Summary and Next Steps

Output a summary to the user: the core question, the result, the prototyper's initial recommendation, and the creative-director's final decision. Link to the full report at prototypes/[concept-name]/REPORT.md.

If PROCEED: run /design-system to begin the production GDD for this mechanic, or /architecture-decision to record key technical decisions before implementation.

If PIVOT or KILL: no further action needed — the prototype report is the deliverable.

Verdict: COMPLETE — prototype finished. Recommendation is PROCEED, PIVOT, or KILL based on findings above.

Important Constraints

• Prototype code must NEVER import from production source files
• Production code must NEVER import from prototype directories
• If the recommendation is PROCEED, the production implementation must be written from scratch — prototype code is not refactored into production
• Total prototype effort should be timeboxed to 1-3 days equivalent of work
• If the prototype scope starts growing, stop and reassess whether the question can be simplified

Recommended Next Steps

• If PROCEED: Run /design-system [mechanic] to author the production GDD, or /architecture-decision to record key technical decisions before implementation
• If PIVOT: Run /prototype [revised-concept] to test the adjusted direction
• If KILL: No further action required — the prototype report is the deliverable
• Run /playtest-report to formally document any playtest sessions conducted during prototyping