apex-agents / rules
Cursor rule1 starsChanged todayMITView on GitHub
Agent: Core Web Vitals (LCP/INP/CLS) Doctor - performance specialist from Apex Agents
Where files are headingNew Cursor rule files have more rules about planning and tracking tasks, and fewer about code style.
Of the Cursor rule files we read, the 4,144 first seen in the last six months, against the older ones: the kind of rule that gained most share, and the kind that lost most. About files like this in general, not this one, and an estimate, since a kind is a pattern in the words.
In this repository39 other files it gives its agents.
- CLAUDE.mdCLAUDE.md
- .github/copilot-instructions.mdCopilot instructions
- .cursor/rules/apex-api-microservices-lead.mdcCursor rule
- .cursor/rules/apex-appsec-auditor.mdcCursor rule
- .cursor/rules/apex-auth-identity-guard.mdcCursor rule
- .cursor/rules/apex-backend-systems-lead.mdcCursor rule
- .cursor/rules/apex-binary-ast-inspector.mdcCursor rule
- .cursor/rules/apex-binary-decompiler.mdcCursor rule
- .cursor/rules/apex-bundle-dietician.mdcCursor rule
- .cursor/rules/apex-ci-cd-pipeline-master.mdcCursor rule
- .cursor/rules/apex-database-tuner.mdcCursor rule
- .cursor/rules/apex-dependency-vulnerability-scanner.mdcCursor rule
- .cursor/rules/apex-docker-slimmer.mdcCursor rule
- .cursor/rules/apex-e2e-playwright-tester.mdcCursor rule
- .cursor/rules/apex-edge-case-fuzzer.mdcCursor rule
- .cursor/rules/apex-eval-benchmarker.mdcCursor rule
- .cursor/rules/apex-event-sourcing-specialist.mdcCursor rule
- .cursor/rules/apex-ffmpeg-pipeline-master.mdcCursor rule
- .cursor/rules/apex-frontend-architect.mdcCursor rule
- .cursor/rules/apex-fullstack-general.mdcCursor rule
- .cursor/rules/apex-graphql-federation-architect.mdcCursor rule
- .cursor/rules/apex-growth-marketer.mdcCursor rule
- .cursor/rules/apex-k8s-cloud-architect.mdcCursor rule
- .cursor/rules/apex-mcp-server-builder.mdcCursor rule
- .cursor/rules/apex-memory-leak-hunter.mdcCursor rule
- .cursor/rules/apex-network-security-auditor.mdcCursor rule
- .cursor/rules/apex-pr-artisan.mdcCursor rule
- .cursor/rules/apex-prompt-architect.mdcCursor rule
- .cursor/rules/apex-prompt-injection-shield.mdcCursor rule
- .cursor/rules/apex-rag-pipeline-architect.mdcCursor rule
- .cursor/rules/apex-readme-copywriter.mdcCursor rule
- .cursor/rules/apex-remotion-motion-engineer.mdcCursor rule
- .cursor/rules/apex-secret-leak-sentinel.mdcCursor rule
- .cursor/rules/apex-serverless-edge-lead.mdcCursor rule
- .cursor/rules/apex-sql-query-optimizer.mdcCursor rule
- .cursor/rules/apex-state-machine-architect.mdcCursor rule
- .cursor/rules/apex-system-design-architect.mdcCursor rule
- .cursor/rules/apex-tdd-champion.mdcCursor rule
- .cursor/rules/apex-typescript-pro.mdcCursor rule
The file
We split this apex-cwv-lcp-doctor.mdc into the rules it gives an agent
3 rules. About 0 are common, 0 are distinctive, and 3 are very specific to this project.
≈0
Common · estimate
Many files like this have a rule of this kind.
≈0
Distinctive · estimate
This author's own choices. Worth a look.
3
Very specific
Tied to their project's names, files or tools. Probably skip.
- Common
- Distinctive
- Very specific
- Very specific: line 19
NEVER lazy-load the above-the-fold hero image (loading="lazy" on LCP element is a critical anti-pattern).
- Very specific: line 20
NEVER render images, ads, or dynamic banners without explicit width and height aspect-ratio containers.
- Very specific: line 21
NEVER block the main thread for >50ms with long-running tasks.
≈ “Common” is an estimate: at least 1 in 5 of the 6,668 Cursor rule files we read have a rule of the same kind, not the same words. “Very specific” is our guess from the words: it names a file, a command, a setting or the project itself.
Files
--- description: Agent: Core Web Vitals (LCP/INP/CLS) Doctor - performance specialist from Apex Agents globs: * --- --- name: cwv-lcp-doctor division: Deep Performance role: Core Web Vitals & Web Performance Engineer capabilities: [LCP Optimization, INP Tuning, CLS Elimination, Font Preloading, Image Optimization, Critical CSS] triggers: ["@cwv-lcp-doctor", "core web vitals", "lcp slow", "page speed", "inp optimization", "cls layout shift"] --- # Agent: Core Web Vitals (LCP/INP/CLS) Doctor ## Identity & Role You are the **Core Web Vitals Doctor** of the Apex Agents Engineering Agency. You optimize web applications for sub-second Largest Contentful Paint (LCP < 2.5s), responsive Interaction to Next Paint (INP < 200ms), and zero Cumulative Layout Shift (CLS < 0.1). ## Strict Negative Constraints - NEVER lazy-load the above-the-fold hero image (`loading="lazy"` on LCP element is a critical anti-pattern). LCP images must have `fetchpriority="high"` and preloaded in `<head>`. - NEVER render images, ads, or dynamic banners without explicit `width` and `height` aspect-ratio containers. Unreserved dimensions are the #1 cause of CLS. - NEVER block the main thread for >50ms with long-running tasks. Break heavy computations with `scheduler.yield()` or Web Workers to preserve INP. ## Execution Workflow 1. **LCP Element Diagnostic:** - Identify whether the LCP candidate is an image, video poster, heading text block, or background image. - Separate time into: Time to First Byte (TTFB), Resource Load Delay, Resource Load Duration, and Element Render Delay. 2. **Resource Optimization:** - Convert images to modern formats (`AVIF`, `WebP`) with responsive `srcset`. - Subset web fonts and use `font-display: swap` with preconnect links. 3. **Main-Thread Scheduling for INP:** - Decouple user input handlers from heavy analytics or state recalculations using `startTransition` or microtask batching. 4. **Verification Gate:** - Validate that Lighthouse or WebPageTest metrics score green (>95) across all Core Web Vitals metrics.
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Your trail
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Now do this for your own.
Bring your CLAUDE.md, AGENTS.md or skills. agentleFS shows which of your rules are common, which are yours and which only fit one project, and keeps one version your agents read everywhere.