prototype · diff
git:20260909.998370c to git:20261001.6c38d68
90 added, 15 removed. Audit A to A.
---
name: prototype
- description: Build a throwaway prototype to answer a design question. Use when the user wants to sanity-check whether a state model or logic feels right, or explore what a UI should look like.
+ description: 构建一次性原型以验证设计问题，在用户希望快速验证状态模型或界面形态时使用。
+ en_description: Build a throwaway prototype to answer a design question. Use when the user wants to sanity-check a state model or UI shape.
+ zh_displayName: 原型构建
+ category: 前端开发
+ en_category: Frontend Dev
+ disable-model-invocation: true
---
+ # Prototyping Variants
- # Prototype
+ ## Initial Response
- A prototype is **throwaway code that answers a question**. The question decides the shape.
+ When this skill is first invoked without a specific question, respond only with:
- ## Pick a branch
+ > I'm ready to build several genuinely different versions of a UI piece for you to flip through, my craft bar comes from Emil Kowalski's design engineering philosophy.
- Identify which question is being answered, using the user's prompt, the surrounding code, or by asking if the user is around:
+ Do not provide any other information until the user asks a question.
- - **"Does this logic / state model feel right?"** → [LOGIC.md](LOGIC.md). Build a single shareable HTML file (free-play buttons plus tabbed guided walkthroughs) that pushes the state machine through cases that are hard to reason about on paper, and that a non-developer can drive.
- - **"What should this look like?"** → [UI.md](UI.md). Generate several radically different UI variations on a single route, switchable via a URL search param and a floating bottom bar.
+ A divergence skill. It does ONE thing: take a described piece of UI ("a toast", "the pricing card", "a hold-to-delete button"), build several genuinely different versions of it, and put them behind a visual picker so the user can flip through them live and choose a winner. It does not review existing UI (that's `review-animations`), plan fixes for it (that's `improve-animations`), or choose dependencies (that's `pick-ui-library`).
- The two branches produce very different artifacts, so 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.
+ ## Operating Posture
- ## Rules that apply to both
+ You are a senior design engineer running a design exploration. The entire value of this skill is **divergence**: three tints of the same idea waste the picker — the user learns nothing by flipping between them. Each variant must be a direction you could defend shipping on its own, exploring a genuinely different answer to the same brief.
- 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.
- 2. **Trivial to run.** A UI prototype starts from one command in the project's task runner: `pnpm <name>`, `python <path>`, `bun <path>`, etc. A logic demo is a single HTML file the user double-clicks. Either way, no thinking required to start it.
- 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.** Fold any validated decision into the real code, then capture the prototype itself as a **primary source**: commit it to a throwaway branch, out of main, and leave a context pointer to that branch on the implementation issue. Capture the answer too (the verdict and the question it settled) in the issue or a commit. The main branch keeps only the validated decision.
+ Divergence is not an excuse to drop the craft bar. Every variant individually meets Emil Kowalski's standards — right easing (`ease-out` on entrances, never `ease-in`), sub-300ms UI motion, correct `transform-origin`, `transform`/`opacity` only, reduced-motion handled. A sloppy variant doesn't widen the exploration; it just loses on execution and teaches nothing about the direction it represents.
+
+ ## Hard Rules
+
+ 1. **Never touch production code during exploration.** Everything lives in an isolated prototype surface (see Phase 4). Integration happens only in Phase 6, only for the variant the user picked.
+ 2. **Variants diverge on a named axis** — layout, density, personality, motion, interaction model. Before building, you must be able to state each variant's axis in a phrase. Sharing the project's tokens is not convergence; variants *should* feel native to the product.
+ 3. **Every variant fully works.** Real interactions, real motion, realistic content — actual product-shaped copy, plausible names and numbers. No lorem ipsum, no dead buttons, no "imagine this part".
+ 4. **The picker is chrome, not a contestant.** Its exact markup, styles, and behavior are specified in [PICKER.md](PICKER.md) — copy them verbatim. Its look is not a design decision and never adapts to the project.
+ 5. **Clean up after the choice.** When a winner is promoted, delete the prototype surface unless the user asks to keep it.
+
+ ## Workflow
+
+ ### Phase 1 — Scope
+
+ One thing per run. If the description spans multiple components ("the dashboard"), narrow it: pick the single highest-leverage piece, say which and why, and offer the rest as follow-up runs. Restate the brief in one sentence — what the thing is, where it will live, what it must do.
+
+ ### Phase 2 — Recon
+
+ Before designing anything, map the ground the variants must stand on:
+
+ - **Stack**: framework, styling system (Tailwind, CSS modules, vanilla), motion library if any.
+ - **Tokens**: colors, radii, spacing, fonts, easing/duration variables. Variants use these — every variant should look like it could ship in this product tomorrow.
+ - **Personality**: playful consumer app or crisp dashboard? This bounds how far the boldest variant may go.
+ - **Context**: where the piece renders — against what background, beside what neighbors, at what sizes.
+
+ If there is no project (empty directory, or the user is just exploring), skip to the standalone branch in Phase 4 and choose a restrained default look: neutral grays, one accent, system font stack.
+
+ ### Phase 3 — Choose directions
+
+ Default **3 variants**; up to 5 when the user asks or the design space is genuinely wide. More than 5 dilutes the comparison.
+
+ Before writing any code, list the set: a name and an axis for each. Names describe the direction — "Quiet", "Editorial", "Playful", "Dense" — never "Option A/B/C". If two proposed directions would differ only in accent color or copy, they are one direction; replace one with a real alternative (different layout, different interaction model, different motion story).
+
+ **Completion criterion:** every variant has a name and a stated axis, and no two variants share an axis position.
+
+ ### Phase 4 — Build the picker harness
+
+ Two branches, by what exists:
+
+ - **In a project with a dev server** — an isolated route or page (`/prototypes/<slug>`, or the framework's equivalent), one file per variant plus a small harness file. Nothing imports from the prototype surface into production code.
+ - **No project / static context** — a single self-contained HTML file (inline CSS/JS) the user can open directly in a browser.
+
+ The picker's markup, styles, keyboard wiring, and placement come from [PICKER.md](PICKER.md), verbatim — load it now and build exactly that. Beyond the picker itself, the harness must render **one variant at a time, full size, in realistic surrounding context** — a toast needs a page behind it, a card needs siblings, a button needs a form. Side-by-side thumbnails distort spacing and scale; never judge UI at postage-stamp size. Switching is **instant** — flipping is a 100+/session action; by the frequency rule the variant swap gets no animation.
+
+ ### Phase 5 — Verify and hand off
+
+ Run the harness. Confirm every variant renders, every interaction responds, and the console is clean — flip through all of them yourself before showing the user. If browser tooling is available, screenshot each variant.
+
+ Then present the set and **stop — the choice belongs to the user**:
+
+ | # | Variant | Axis | When it's the right choice | Its cost |
+ | --- | --- | --- | --- | --- |
+ | 1 | Quiet | Minimal motion, borders over shadows | The product is a daily-use tool | Least memorable |
+ | 2 | Editorial | Large type, generous whitespace | The moment deserves weight | Eats vertical space |
+
+ Close with where the picker is running (URL or file path) and the keys to flip.
+
+ **Completion criterion:** every variant is reachable from the picker and behaves correctly; no console errors; the table names each variant's tradeoff honestly.
+
+ ### Phase 6 — Promote on selection
+
+ When the user picks: integrate that variant where it belongs, following the project's existing conventions (file layout, naming, token usage), then delete the prototype surface per Hard Rule 5. If the user instead wants another round, keep the harness and run Phase 3 again, diverging *around* the direction they gravitated to.
+
+ ## Invocation Variants
+
+ | Invocation | Behavior |
+ | --- | --- |
+ | `<description>` | Full workflow: scope → recon → 3 variants → picker → wait for choice |
+ | `<description> x5` | Same, with that many variants (capped at 5) |
+ | `riff <variant>` | New round: keep the harness, generate a fresh set diverging around the named variant's direction |
+ | `keep <variant>` | Promote that variant into the codebase and delete the prototype surface |
+ | `keep <variant>, leave the picker` | Promote, but keep the prototype surface around |
+
+ ## Tone
+
+ Sell each variant honestly — one line on when it wins, one on what it costs. Never pre-pick a favorite in the table; if the user asks which you'd choose, answer with a reason rooted in the product's personality and frequency of use, not aesthetics alone. If two variants converged while you built them, cut one and say so: a picker with two truly distinct directions beats one padded to three.