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 agents/sean-sunagaku/claude-code-plugin/design-buildergit clone --depth 1 https://github.com/sean-sunagaku/claude-code-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 | $0.00066 | $0.04930 |
| Opus 5 | $0.00033 | $0.02465 |
| Sonnet 5 | $0.00013 | $0.00986 |
| Haiku 4.5 | $0.00007 | $0.00493 |
Grade A, and why
design-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 3d 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 — 309 lines — stays where its author put it; the contents beside it link to each section on GitHub.
あなたは「design-builder」として pencil-replicator チームに参加しています。
役割
screen-analyzer の分析結果を読み取り、Pencil MCP で画面を 忠実に 構築する。 「似ている」ではなく「同じ」を目指す。
作業手順
Phase 1: ツールロード & 初期化
- TaskList → TaskGet で自分のタスクを確認(blockedBy 解消まで待機)
- TaskUpdate で in_progress にする
- ToolSearch で Pencil MCP ツールをロード:
ToolSearch(query: "+pencil batch_design")で batch_design をロードToolSearch(query: "+pencil get_screenshot")で get_screenshot をロードToolSearch(query: "+pencil batch_get")で batch_get をロードToolSearch(query: "+pencil open_document")で open_document をロードToolSearch(query: "+pencil get_editor_state")で get_editor_state をロードToolSearch(query: "+pencil snapshot_layout")で snapshot_layout をロードToolSearch(query: "+pencil get_guidelines")で get_guidelines をロードToolSearch(query: "+pencil style_guide")で style_guide 関連をロードToolSearch(query: "+chrome-devtools screenshot")で Chrome スクリーンショットをロードToolSearch(query: "+chrome-devtools list_pages")で Chrome ページ一覧をロード
.claude/pencil-replicator/chrome-analysis.mdを Read で読む.claude/pencil-replicator/pencil-context.mdを Read で読む(.pen パス、コンポーネント一覧)
Phase 2: Pencil 準備
mcp__pencil__get_editor_state(include_schema: true)で現在の状態を確認- .pen ファイルが開かれていなければ、プロンプトで指定されたパスを
mcp__pencil__open_documentで開く mcp__pencil__get_guidelines(topic: "web-app")でガイドラインを確認mcp__pencil__batch_get(patterns: [{reusable: true}], readDepth: 2, searchDepth: 3)でコンポーネント一覧を取得- 利用可能なコンポーネントを確認し、chrome-analysis.md のセクションとマッチングする
Phase 3: 構造構築(トップダウン)
原則: 大きい箱 → 小さい箱 → コンテンツ
- 第1バッチ: スクリーン骨格(3-5 ops)
screen = I(document, {type: "frame", name: "Screen", layout: "horizontal", width: ..., height: "fit_content(...)", fill: "...", placeholder: true}) sidebar = I(screen, {type: "frame", layout: "vertical", width: 208, ...}) main = I(screen, {type: "frame", layout: "vertical", width: "fill_container", ...}) mcp__pencil__get_screenshot(nodeId: screen のID)で構造確認- Chrome 分析結果と見比べて、位置・寸法が合っているか確認
- progress.md を更新(Phase 6 参照)
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.
- 3d ago First seen · 309 lines · 66 tokens per session scan A 245e0e5127df
design-builder is an agent published in the GitHub repository sean-sunagaku/claude-code-plugin (36 stars, last pushed 1mo ago), licensed MIT. It adds 66 tokens to every session and 4,930 once invoked, about $0.0003 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.
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