Prototype

A prototype is throwaway code that answers a question. The question decides the shape.

Pick a branch

Identify which question is being answered — from the user's prompt, the surrounding code, or by asking if the user is around:

• "Does this logic / state model feel right?" → LOGIC.md. Build a tiny interactive terminal app that pushes the state machine through cases that are hard to reason about on paper.
• "What should this look like?" → UI.md. Generate several radically different UI variations on a single route, switchable via a URL search param and a floating bottom bar.

The two branches produce very different artifacts — getting this wrong wastes the whole prototype. If the question is genuinely ambiguous and the user isn't reachable, default to whichever branch better matches the surrounding code (a backend module → logic; a page or component → UI) and state the assumption at the top of the prototype.

Rules that apply to both

1. Throwaway from day one, and clearly marked as such. Locate the prototype code close to where it will actually be used (next to the module or page it's prototyping for) so context is obvious — but name it so a casual reader can see it's a prototype, not production. For throwaway UI routes, obey whatever routing convention the project already uses; don't invent a new top-level structure. Never put ticket IDs inside prototype files.
2. One command to run. Whatever the project's existing task runner supports — pnpm <name>, python <path>, bun <path>, etc. The user must be able to start it without thinking.
3. No persistence by default. State lives in memory. Persistence is the thing the prototype is checking, not something it should depend on. If the question explicitly involves a database, hit a scratch DB or a local file with a clear "PROTOTYPE — wipe me" name.
4. Skip the polish. No tests, no error handling beyond what makes the prototype runnable, no abstractions. The point is to learn something fast.
5. Surface the state. After every action (logic) or on every variant switch (UI), print or render the full relevant state so the user can see what changed.
6. Capture it when done — the decision is the durable thing, not the code. Record on the ticket: the question, the verdict, and the decision-rich excerpt (a state machine, reducer, schema, or type shape — trimmed to the decision, never a working demo). The prototype itself stays disposable: a local throwaway branch or worktree, never pushed, never through the publishing chain — its loss costs nothing once the ticket holds the decision.

Map contexts (estate override)

Inside a wayfinder map, nothing folds into real code at prototype close — LOGIC.md's "lift into the real module" and UI.md's "fold the winner" steps apply only outside maps. Phase one makes throwaway artifacts, never durable mutations: the decision lands on the ticket, and phase two's build slices do the folding, through the same gates every slice uses. UI.md's shared switcher lives with the prototype, not in shared UI. Non-code prototypes (an outline, a rough take, a sketch) follow the same rules minus the run command — the artifact attaches to the ticket as a document, or links from where it lives.