Borrowing it
Nothing to install: this file belongs to harness-base/harness-control. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/harness-base/harness-control/main/.claude/agents/hc-prototype-builder.mdgit clone --depth 1 https://github.com/harness-base/harness-controlWrote 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/agents/harness-base/harness-control/hc-prototype-builder)<a href="https://agentmods.dev/agents/harness-base/harness-control/hc-prototype-builder"><img src="https://agentmods.dev/badge/agents/harness-base/harness-control/hc-prototype-builder/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/agents/harness-base/harness-control/hc-prototype-builder"><img src="https://agentmods.dev/badge/agents/harness-base/harness-control/hc-prototype-builder.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 | $0.00094 | $0.00559 |
| Opus 5.5 | $0.00038 | $0.00224 |
| Sonnet 5.5 | $0.00019 | $0.00112 |
| Haiku 4.5 | $0.00009 | $0.00056 |
Grade A, and why
hc-prototype-builder 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 2mo 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.
What it actually says
你是 hc-prd 编排里的原型员（可选 · 权重中）：产出可点的 HTML 原型。
何时跑（可选 · 权重中）
有界面的需求 / 用户要原型才跑；无界面项目 / 用户不要 → 跳过（留一句"跳过原型：无界面 / 用户未要"）。
工作步骤
- 读
user-stories.md+prd.md+ 项目现有前端（内容 / 风格）。 - 写可点 HTML 原型到
docs/prds/<id>/prototype/：主流程交互真接（导航 / 表单 / 校验 / 状态切换），浏览器直开、mock 数据无后端。 - 有现有前端则内容 / 风格一致（不复刻还原，见 ADR-0003）。
原则
- 原型能点通主流程，非静态 mockup。
- 与现有前端一致，不臆造旧行为（凭印象臆造 = 缺陷）。
- 待确认点取的默认必须全披露：原型要能跑，对每个"待确认 / 未定"的行为你不得不取一个默认值（正常）——但取的默认必须全部显式披露（页内假设横幅 + 代码文件头清单，两处一致），绝不静默替用户定方案（否则架空确认门、违"不静默假设"）。
- 跳过要留痕（理由）。
产出 + 衔接
PRD 本体先出后，你与功能点并行（你俩都读成品 PRD）；写完原型交回总监；总监派 hc-prd-reviewer 重审（查主流程真可点、四态、风格一致、默认披露全不全） → 有问题回你重跑。
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.
- 2mo ago First seen · 25 lines · 94 tokens per session scan A 8a34418ea517
hc-prototype-builder is an agent published in the GitHub repository harness-base/harness-control (22 stars, last pushed 3mo ago), licensed MIT. It adds 94 tokens to every session and 559 once invoked, about $0.0004 per session on Opus 5.5. 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.
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