Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add commands/volomydyr/design-engineer-plugin/prototypegit clone --depth 1 https://github.com/volomydyr/design-engineer-pluginWhat it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5 | $0.00025 | $0.00625 |
| Opus 5 | $0.00013 | $0.00313 |
| Sonnet 5 | $0.00005 | $0.00125 |
| Haiku 4.5 | $0.00003 | $0.00063 |
Grade A, and why
design-engineer:prototype scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
How it starts
The opening of the file, as written. The whole thing — 73 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Prototype
Plugin paths
Your conversation context contains a line DESIGN_ENGINEER_PLUGIN_ROOT: <absolute path> injected by the plugin's UserPromptSubmit hook. Whenever this command references ${DESIGN_ENGINEER_PLUGIN_ROOT}/..., substitute the absolute path from that context line. No shell commands are run from this command body.
Context
#$ARGUMENTS
Generate a single-file HTML prototype using the dev-prototyping skill.
Step 1: Read project context
- Read
.design-engineer-plugin/config.yamlfor mode (guided/autopilot) - Check what design deliverables exist (design/ – problem statement, IA, user flows, etc.)
- Check if Figma is connected
Step 2: Plan
Present what the prototype will be based on:
Here's what I have to work with:
{List available context: design docs, Figma designs, user description, etc.}
I'll build a clickable HTML prototype that covers {scope}. Want to adjust?
If an argument was provided:
new→ prototype for a new product from scratchfeature→ prototype for a new feature in the existing productredesign→ prototype to replace an existing feature
Confirm the selection: "Starting a prototype for {type} – correct?"
In Guided mode: discuss scope and approach before building. In Autopilot: show plan briefly, then build.
Step 3: Execute
Read ${DESIGN_ENGINEER_PLUGIN_ROOT}/skills/dev-prototyping/SKILL.md and follow its full 7-step flow. Do NOT use the Skill tool — plugin skills set disable-model-invocation: true.
In Guided mode: pause after the initial prototype for review, iterate based on feedback. In Autopilot: build the prototype, present it, ask for feedback.
Note: do NOT run /simplify on prototype HTML. Prototypes are throwaway visual artifacts; code quality is irrelevant in this phase. /simplify applies only during /design-engineer:development implementation.
Step 4: Test
Use the test-writer agent to create test scripts that verify prototype behavior. Run tests to confirm they pass.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 73 lines · 25 tokens per session scan A d149f67f7a15
design-engineer:prototype is a command published in the GitHub repository volomydyr/design-engineer-plugin (19 stars, last pushed 1mo ago), licensed MIT. It adds 25 tokens to every session and 625 once invoked, about $0.0001 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
Other commands, from other repositories
checklist
Generate a custom checklist for the current feature based on user requirements.
clarify
Identify underspecified areas in the current feature spec by asking up to 5 highly targeted clarification questions and encoding answers back into the spec.
specify
Create or update the feature specification from a natural language feature description.
analyze
Perform a non-destructive cross-artifact consistency and quality analysis across spec.md, plan.md, and tasks.md after task generation.
converge
Assess the current codebase against the feature's spec, plan, and tasks, then append any remaining unbuilt work as new tasks to tasks.md so implement can complete it.
implement
Execute the implementation plan by processing and executing all tasks defined in tasks.md.