prototype
What it does¶
prototype builds a rough, disposable version of something to answer one question: does this state model hold up, or which of these layouts works. It states the question before it builds anything, since a polished prototype of the wrong question teaches nothing.
The code is thrown away, but the answer is not. The prototype lives on its own prototype/<slug> branch, which is never merged, and only the decision it settled is carried into the real branch, rewritten with tests.
When to reach for it¶
Type /prototype, or let the agent start it when a task fits. Use it when a question stays open however long you talk: transitions you cannot keep straight in your head, or a screen you cannot judge until three versions sit side by side. wayfinder can also put a prototype ticket on its map, which you settle with this skill.
| Your situation | Use |
|---|---|
| A design question that talking has not settled | prototype |
| A question that a document or an API can answer | research |
| Something already built is misbehaving | diagnosing-bugs |
| A plan that needs challenging, not trying | grill |
prototype sits on the planning side of the Epic path, and inside unknown territory as one of wayfinder's four ticket types. ask-spp routes between every skill when the right one is unclear.
Two shapes¶
The question picks the shape.
| You are asking | You get |
|---|---|
| What happens when events arrive in this order | A single HTML page that drives a small pure module. It shows the state in labelled fields, a button for every action, and one tab per scenario to walk through. |
| What should this look like | Three to five structurally different variants on one route, switched with a bar at the bottom of the screen and a ?variant= parameter in the URL. |
The logic page opens by double-click and speaks the domain's words, so a designer or a domain expert can drive it without help. The UI variants sit inside the real page, among its real data, since any variant looks fine on a bare route.
Common questions¶
Does the prototype get deleted?
No. Delete it and the next reader has only a summary of what you saw. It stays on its prototype/<slug> branch as the evidence for the answer, and the record of the verdict names that branch. What never happens is a merge.
Can I turn the prototype into the real thing? Carry the decision across, not the code. The one exception is a pure logic module, once tests pin its behaviour. The rest was written with no tests and no error handling, so it is rewritten under the project's normal standards.
An agent suggested a prototype when I knew what to build. A prototype answers a question that is still open. When the design is settled, go to implementation. When one choice is unsettled, prototype only that choice.
It's working if¶
Look at what is left after a prototype session and you should find:
- A pushed
prototype/<slug>branch with no pull request against it, and an untouched branch you started from. - A question in the prototype's own intro, which you can read without opening any code.
- A comment on the issue, or a final commit message, that gives the question, the person's verdict and the branch name.
- No write to a database, file or service outside a scratch location the prototype named as wipeable. Reads are fine: UI variants render live data.
- On the real branch afterwards, only the decision, written with tests. Nothing from
prototype/is there.