{
  "id": "web-performance-core-vitals-agent",
  "name": "Web Performance & Core Web Vitals",
  "type": "agent",
  "provider": "frontend",
  "harnesses": [
    "codex",
    "copilot",
    "claude-code",
    "cursor",
    "gemini",
    "kiro"
  ],
  "summary": "Static/read-only review agent that triages Core Web Vitals (LCP, INP, CLS) using both lab and field evidence, ties every verdict to a numeric budget and business metric, and refuses lab-only sign-off.",
  "source_type": "adapted",
  "official_docs": [
    "https://web.dev/articles/vitals",
    "https://web.dev/articles/lcp",
    "https://web.dev/articles/inp",
    "https://web.dev/articles/cls",
    "https://web.dev/articles/lighthouse-performance",
    "https://developer.chrome.com/docs/crux",
    "https://developer.mozilla.org/en-US/docs/Web/API/PerformanceObserver",
    "https://developer.mozilla.org/en-US/docs/Glossary/Time_to_first_byte",
    "https://www.w3.org/TR/largest-contentful-paint/",
    "https://www.w3.org/TR/event-timing/",
    "https://www.w3.org/TR/layout-instability/"
  ],
  "security_notes": "Never request production analytics credentials, CrUX API keys, or customer PII to produce a verdict; accept sanitized/aggregated exports only. Do not recommend third-party RUM beacons without disclosing their own script-execution and privacy/cost trade-off. Treat any request to strip loading-state accessibility semantics (aria-live, role=status) purely to shave CLS as a hard reject, not a stylistic choice.",
  "last_verified": "2026-07-02",
  "path": "agents/frontend/web-performance-core-vitals-agent",
  "harness_variants": {
    "codex": "agents/frontend/web-performance-core-vitals-agent/harnesses/codex.toml",
    "copilot": "agents/frontend/web-performance-core-vitals-agent/harnesses/copilot.agent.md",
    "claude-code": "agents/frontend/web-performance-core-vitals-agent/harnesses/claude-code.agent.md",
    "cursor": "agents/frontend/web-performance-core-vitals-agent/harnesses/cursor.agent.md",
    "gemini": "agents/frontend/web-performance-core-vitals-agent/harnesses/gemini.agent.md",
    "kiro-ide": "agents/frontend/web-performance-core-vitals-agent/harnesses/kiro-ide.agent.md",
    "kiro-cli": "agents/frontend/web-performance-core-vitals-agent/harnesses/kiro-cli.agent.json"
  },
  "companion_skills": [],
  "execution_tier": "static-review",
  "author": "github: VincentChuWaiChow",
  "version": "0.1.0"
}