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 skills add solofounder-ai/solofounder --skill mockup-servergit clone --depth 1 https://github.com/solofounder-ai/solofounderWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/solofounder-ai/solofounder/mockup-server)<a href="https://agentmods.dev/skills/solofounder-ai/solofounder/mockup-server"><img src="https://agentmods.dev/badge/skills/solofounder-ai/solofounder/mockup-server/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/skills/solofounder-ai/solofounder/mockup-server"><img src="https://agentmods.dev/badge/skills/solofounder-ai/solofounder/mockup-server.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What 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 5.1 | $0.00030 | $0.00589 |
| Opus 5 | $0.00015 | $0.00295 |
| Sonnet 5 | $0.00006 | $0.00118 |
| Haiku 4.5 | $0.00003 | $0.00059 |
Grade A, and why
mockup-server 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 10d 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 — 74 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Mockup Server
Overview
Browser-based visual companion for showing mockups, diagrams, design variants, and interactive options. Agents write HTML files, the server serves them on localhost, users view and vote in their browser.
Core principle: Decide per-question, not per-session. The test: would the user understand this better by seeing it than reading it?
When to Use
Use the browser when the content itself is visual:
- UI mockups, wireframes, layout comparisons
- Architecture diagrams, data flow visualizations
- Side-by-side design variant comparison
- Design system showcases (color palettes, typography, components)
- Any content where spatial relationships matter
Use the terminal when the content is text:
- Requirements questions, conceptual choices
- Tradeoff lists, comparison tables
- Technical decisions, API design
- Clarifying questions
Quick Reference
Start server:
capabilities/mockup-server/scripts/start-server.sh --project-dir /path/to/project
Write content: Use the Write tool to create HTML files in screen_dir. Write content fragments (no <html> wrapper needed — server adds the frame template automatically).
Read user interactions: Check state_dir/events for click/vote/feedback events as JSONL.
Stop server:
capabilities/mockup-server/scripts/stop-server.sh $SESSION_DIR
Multi-Variant Comparison
When multiple agents produce design variants, use the variant- filename prefix:
content/
variant-a-minimal.html
variant-b-bold.html
variant-c-rounded.html
The server auto-generates a comparison view. Users can vote on variants and provide per-variant feedback.
Event types:
{"type":"vote","variant":"variant-a-minimal","timestamp":...}
{"type":"feedback","variant":"variant-b-bold","text":"like the colors","timestamp":...}
{"type":"merge","from":["variant-a","variant-b"],"note":"A's layout + B's colors","timestamp":...}
Design Research Gallery
When presenting curated design references from solofounder:live-research, use the design research gallery pattern. This shows references as visual cards with images, multi-select for picking favorites, AI combination suggestions, and a refinement flow.
What ships with it
7 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 10d ago First seen · 74 lines · 30 tokens per session scan A fbcae842d821
mockup-server is a skill published in the GitHub repository solofounder-ai/solofounder (3 stars, last pushed 5mo ago), licensed MIT. It adds 30 tokens to every session and 589 once invoked, about $0.0002 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 2026-08-31.
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