prototype

Generated source view for the actual executable engineering/prototype skill. The durable routing article is Agent Engineering Skills. Source: skills/engineering/prototype/SKILL.md

Runtime Source

Bundled Resources

These files are part of the executable skill folder and must be preserved with the skill source.

Description

Build a throwaway prototype to answer one design question. Use when the user asks to prototype, spike, explore a design, compare UI variants, test a state machine, or flesh out a PRD decision before committing to production code. Adapted from mattpocock/skills.

Skill Source

---
name: prototype
description: Build a throwaway prototype to answer one design question. Use when the user asks to prototype, spike, explore a design, compare UI variants, test a state machine, or flesh out a PRD decision before committing to production code. Adapted from mattpocock/skills.
origin: personal
source_slug: prototype
---

# Prototype

A prototype is throwaway code that answers one question. Keep the answer; delete or
quarantine the code.

## Pick A Branch

**LOGIC prototype**: use for state machines, business rules, scheduling, pricing,
authorization, parsing, or data flow. Build a tiny CLI/script/harness that can be run
with fixture inputs.

**UI prototype**: use for interaction, layout, motion, density, or taste. Build several
radically different variants behind a local-only toggle such as `?variant=a`, a demo
route, or a floating dev control.

Read `LOGIC.md` for the terminal/state-machine prototype branch. Read `UI.md` for the
multi-variant browser prototype branch.

## Guardrails

- State the single question before writing code.
- Put prototypes under `prototypes/`, `experiments/`, `app/prototypes/`, or a clearly
  local demo route.
- Do not let prototype code become production by inertia.
- Record the answer in a PRD, ADR, issue, or notes file.
- Remove or quarantine prototype code before shipping unless Kevin explicitly promotes it.

## Output

```markdown
## Prototype Result

Question:
Answer:
Variants tried:
Evidence:
Decision captured in:
What to delete:
```

## Related Skills

- `grill-with-docs` to discover which question deserves prototyping.
- `to-prd` to absorb the answer into a product spec.
- `frontend-design` / `web-design-engineer` for production UI after the prototype.

Upstream: `github.com/mattpocock/skills/skills/engineering/prototype/SKILL.md`
at `5d78bd0903420f97c791f834201e550c765699f8`.

---

Timeline

• 2026-07-15 | Generated a browseable source page from the actual executable skill file. Source: skills/engineering/prototype/SKILL.md