spike

name	spike
description	Use when an idea is too fuzzy to spec confidently and a throwaway build would answer faster than more spec work - runs before elicit-requirements or create-prd. Triggers on "spike", "spike this", "prototype this idea", "throwaway prototype".

Spike

Build-first discovery. The spec is a guess; the throwaway build is the elicitation device. Iterate attended until the contract is real, then graduate to a PRD. Nothing built here ships.

Loop

1. Rough spec (10 minutes, no polish)

Write dev/local/spikes/<slug>/SPEC.md (Write tool, never shell redirects):

• The user's idea, verbatim
• The smallest outcome that would demonstrate it end-to-end
• Guessed contract (inputs, outputs, interfaces) - mark each guess (guess)

If the user gave only a phrase, ask at most one question, then guess the rest. Wrong guesses are the point - the build exposes them.

2. Throwaway build (about 20 minutes of work)

Build the smallest thing that demonstrates the idea end-to-end, directly in this session - no implementor dispatch, no TDD ceremony:

• Standalone idea: build inside dev/local/spikes/<slug>/
• Change to existing code: work on branch spike/<slug> (worktree if the working tree is dirty); never the current branch
• Sandbox only: never touch production data, live services, or anything irreversible. Input validation at real trust boundaries stays; tests, changelog, review, and production-ready rules are suspended - this code is disposable by contract
• Timebox: if it will not demonstrate in about an hour of effort, stop and report; the idea is not spike-sized - take the open questions to elicit-requirements instead

3. Report

Show, in this order:

1. What got built and how to run it (2-3 lines plus the run command)
2. ASSUMPTIONS: one line per choice made where SPEC.md was silent
3. OPEN QUESTIONS: what the build surfaced that the spec must now answer

4. Decide

AskUserQuestion with exactly these three: Refine and re-spike (fold the answers into SPEC.md, rebuild in place, back to step 2), Graduate (step 5), Discard (delete the spike dir or branch, done). Never chain refine cycles without the user - the attended examine step is the value.

5. Graduate

Invoke create-prd with SPEC.md plus the final assumptions and answers. The PRD contract records observed prototype behavior, not the original guesses. Note in the PRD context that the spike exists at dev/local/spikes/<slug>/ (or branch spike/<slug>) as reference.

The real implementation goes through the normal pipeline (plan-tasks, work, full review) and rebuilds from scratch - spike code never merges. Delete the spike once the PRD's implementation lands.