Prototype

prototype: spike to learn, then throw it away

Some uncertainty is cheaper to build through than to talk through. A prototype exists to answer ONE named question; the deliverable is the answer, never the code.

Contract (agree before writing code)

1. The question: one sentence, falsifiable. "Can X stream 10k rows without buffering?" not "explore X".
2. Timebox: default 30 to 60 min of agent work. Hit the box with no answer → that IS a finding (question too big; split it or grill further).
3. Kill criteria: what result answers the question either way.
4. Where it lives: an authorised, manifest-owned scratch dir outside production source. Never import it from real code or touch external systems, credentials or user data without separate authority.

Rules

• Build only the checks needed to answer the question. Production quality gates do not apply to disposable scratch code; evidence, authority and containment do.
• Cheat aggressively: hardcode data, stub auth, fake the network. Only the question's variable needs to be real.
• One question per spike. A second question mid-spike → note it, finish, spike it separately if it still matters.
• Harvest, then retire. Put the finding and evidence in the owning spec, decision record or scoping thread when artifact authority exists. Remove only paths proven run-owned and explicitly authorised; otherwise quarantine or hand them back with a named cleanup action.
• Prototype code never "graduates" to production. Productionisation routes through scope when decisions changed, then implement; rebuild the smallest production solution with the appropriate test/refactor method.

Harvest format (into the owning doc/thread)

**Spike:** <question>  (YYYY-MM-DD, timebox 45m)
**Answer:** yes/no/partial — <one paragraph, numbers where measured>
**Evidence:** <command run, output, or measurement>
**Implication:** <what the spec/decision now says because of this>

Red flags

• "The spike works, let's ship it" → scope any changed decision, then use implement; do not wire the spike into production.
• Spike touching production files or secrets → wrong dir, stop.
• No timebox agreed → not a spike, just unscoped wandering.
• Answer known from docs/a search in <10 min → didn't need a spike.