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seo-performance

seo-performance

github.com/agricidanielMarketing & growth88574 installsUpdated 1w ago
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About seo-performance

seo-performance is a performance-analysis skill for SEO audits. It prioritizes PageSpeed Insights / CrUX field data and clearly labels lab data or heuristic fallbacks when field data is unavailable.

Key features

  1. 01Checks Lighthouse mobile and desktop scores
  2. 02Measures LCP, CLS, and available INP
  3. 03Reports TBT as a lab proxy when INP is absent
  4. 04Provides fallback guidance when API data is unavailable
  5. 05Produces an audit report and JSON summary
  6. 06Writes results to a shared cache

Use cases

  1. 01Reviewing core web vitals for a page
  2. 02Checking lab data when field data is unavailable
  3. 03Prioritizing performance issues

Install

Copy the command and run it in a terminal.

$npx skills add https://github.com/agricidaniel/codex-seo --skill seo-performance

After installing, type/seo-performancein Claude Code to confirm it loaded.

Details

From the project README

Performance Specialist

Use this for the performance sub-track in full audits.

Shared Data Cache

Step 0 -- Check shared data cache:

Before gathering, check .seo-cache/ for cached data from other skills. Reference: ../seo/references/shared-data-cache.md for schemas and dependency map.

This specialist does not require upstream cache inputs before running fresh performance checks.

  • If found: no prerequisite cache is needed; continue with current measurements
  • If missing: proceed normally and gather fresh performance data
  • If the user says "refresh" or "re-run": ignore cache entirely

Inputs

  • URL
  • Timeout
  • Optional PageSpeed API key (PAGESPEED_API_KEY)

Execution Path

Prefer running scripts/analyze_performance.py for deterministic performance analysis in API/headless environments. The script uses PageSpeed data when available and otherwise falls back to labeled heuristics so the pipeline still completes without a human in the loop.

Outputs

  • PERFORMANCE-AUDIT-REPORT.md
  • SUMMARY.json

Core checks

  • Prefer real-user CWV data from PageSpeed Insights / CrUX when available
  • If real-user data is unavailable, fall back to Lighthouse lab data and label it clearly as lab data
  • Lighthouse performance score (mobile + desktop if available)
  • LCP and CLS measurements
  • INP only when the data source actually provides it; do not fabricate or infer INP from TBT
  • TBT may be reported as a lab proxy when INP is unavailable
  • Fallback guidance when API data is unavailable, quota-blocked, or unauthenticated

Priority Rules

  • High: Performance score < 70 or LCP > 2500ms or INP > 200ms or CLS > 0.1
  • Medium: Performance score 70-79
  • Low: Data-source limitations

Write to shared data cache

After completing all work, write results to .seo-cache/.

mkdir -p .seo-cache/pages/{url-slug}

Write .seo-cache/pages/{url-slug}/performance.json using the schema in ../seo/references/shared-data-cache.md. At minimum, match the documented cache keys: core_web_vitals and issues. Add extra helpful fields only if they do not replace or rename the documented keys.

Add .seo-cache/ to .gitignore if not already present:

grep -qxF '.seo-cache/' .gitignore 2>/dev/null || echo '.seo-cache/' >> .gitignore
Premium Deliverable

If the user requests a 'client report' or 'premium deliverable', automatically read ../seo-audit/assets/report-template.html and ../seo/references/premium-report-standard.md. Use that report standard as the default brief. Generate the HTML as an internal intermediate artifact, then produce the PDF as the public deliverable. Mention only the PDF in your final response unless the user explicitly asks for the HTML file.

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