SEO 可见度诊断（搜索引擎收录分析）

This skill turns a website or brand into a structured traditional-search visibility audit and renders a detailed, self-contained HTML report.

When to use

• User asks "分析一下这个网站在百度/谷歌的收录情况" / "SEO 收录分析" / "我的页面为什么搜不到" / "出一份搜索可见度报告".
• Diagnose index coverage, ranking and SERP presence across Baidu / Bing / Google / Sougou / 360.

Required tools

• WebSearch — real-time SERP checks (use per-engine allowed_domains / blocked_domains to separate engines).
• WebFetch — fetch target pages to verify on-page SEO signals (title / meta / canonical / structured data / internal links).
• Read / Write / Bash (python3) — assemble and write the HTML report.

Audit dimensions (cover all)

1. 收录诊断（Index Coverage）
   - site:domain count per engine (Baidu/Bing/Google/Sougou/360).
   - Spot-check 5–8 key URLs with site:domain "url-path" to confirm indexed vs missing.
   - Robots.txt / noindex / canonical conflicts that block indexing.
2. 排名诊断（Ranking）
   - For 8–12 core keywords, record whether the target ranks in top 10 / top 50 / not found, per engine.
   - Capture current SERP snippet (title + description + any rich result).
3. 页面基础 SEO 信号（on-page）
   - Title length, meta description, H1 uniqueness, image alt, internal-link count, canonical, OpenGraph.
   - Mobile-friendly / HTTPS / load hint (best-effort, label as estimated).
4. 竞品对照（optional but recommended）
   - 1–2 competitors: same site: count + 2 shared keywords ranking gap.
5. 风险与机会清单
   - Blocked-by-robots, thin content, orphan pages, missing structured data, brand-name search not owned.

Search technique (critical)

• Run one WebSearch per engine using allowed_domains to bias results when possible; otherwise note engine in the query string ("百度 site:...").
• For site: counts, read the "约 N 条结果" style number from results; if unavailable, label "未公开/需手动复核".
• Never fabricate index numbers — if a check cannot be confirmed, mark "待人工复核" and explain how.

Report output (detailed HTML)

Render a single self-contained .html (inline CSS, no external deps) with:
- Header: domain, audit date, engines covered, overall visibility score (0–100 heuristic).
- Section 1 收录概览: per-engine site: count table + indexed/missing URL checklist.
- Section 2 排名表现: keyword × engine matrix with color badges (top10 / top50 / none).
- Section 3 页面基础信号: per-URL checklist table.
- Section 4 竞品对照 (if done).
- Section 5 风险清单 + 优化建议 (prioritized P0/P1/P2).
- Footer: methodology note + "数据来自实时搜索，部分指标需人工复核" disclaimer.
- Brand accent: use #2B6CB0 (search blue) for headers/badges.

Write the report to the working directory as seo_visibility_<domain>_<YYYY-MM-DD>.html.
After writing, open a short summary (score + top 3 findings + report path) for the orchestrator.