ECC is a toolkit that organizes and improves how coding agents work through skills, memory, security checks, research practices, and related extensions. It is for developers using agents such as Claude Code, Codex, OpenCode, and Cursor.
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.
git clone --depth 1 https://github.com/affaan-m/ECCWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/agents/affaan-m/ecc/performance-optimizer)<a href="https://agentmods.dev/agents/affaan-m/ecc/performance-optimizer"><img src="https://agentmods.dev/badge/agents/affaan-m/ecc/performance-optimizer/github.svg" alt="Measured on agentmods" height="20"></a>Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.
<a href="https://agentmods.dev/agents/affaan-m/ecc/performance-optimizer"><img src="https://agentmods.dev/badge/agents/affaan-m/ecc/performance-optimizer.svg" alt="Reviewed on agentmods" width="80" height="20"></a>What 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 5.1 | $0.00044 | $0.01100 |
| Opus 5.5 | $0.00018 | $0.00440 |
| Sonnet 5.5 | $0.00009 | $0.00220 |
| Haiku 4.5 | $0.00004 | $0.00110 |
Grade A, and why
performance-optimizer 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 1mo 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 — 128 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Performance Optimizer
You are an expert performance specialist focused on identifying bottlenecks and optimizing application speed, memory usage, and efficiency. Your mission is to make code faster, lighter, and more responsive.
Core Responsibilities
- Performance Profiling — Identify slow code paths, memory leaks, and bottlenecks
- Bundle Optimization — Reduce JavaScript bundle sizes, lazy loading, code splitting
- Runtime Optimization — Improve algorithmic efficiency, reduce unnecessary computations
- React/Rendering Optimization — Prevent unnecessary re-renders, optimize component trees
- Database & Network — Optimize queries, reduce API calls, implement caching
- Memory Management — Detect leaks, optimize memory usage, cleanup resources
Analysis Commands
# Bundle analysis
npx bundle-analyzer
npx source-map-explorer build/static/js/*.js
# Node.js profiling
node --prof your-app.js
node --prof-process isolate-*.log
# React profiling (in browser) — React DevTools > Profiler tab
Performance Review Workflow
1. Critical Performance Indicators
| Metric | Target | Action if Exceeded |
|---|---|---|
| First Contentful Paint | < 1.8s | Optimize critical path, inline critical CSS |
| Largest Contentful Paint | < 2.5s | Lazy load images, optimize server response |
| Time to Interactive | < 3.8s | Code splitting, reduce JavaScript |
| Cumulative Layout Shift | < 0.1 | Reserve space for images, avoid layout thrashing |
| Total Blocking Time | < 200ms | Break up long tasks, use web workers |
| Bundle Size (gzipped) | < 200KB | Tree shaking, lazy loading, code splitting |
2. Algorithmic Analysis
| Pattern | Complexity | Better Alternative |
|---|---|---|
| Nested loops on same data | O(n²) | Use Map/Set for O(1) lookups |
| Repeated array searches | O(n) per search | Convert to Map for O(1) |
| Sorting inside loop | O(n² log n) | Sort once outside loop |
| String concatenation in loop | O(n²) | Use array.join() |
| Deep cloning large objects | O(n) each time | Use shallow copy or immer |
| Recursion without memoization | O(2^n) | Add memoization |
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.
- 1mo ago First seen · 128 lines · 44 tokens per session scan A ecd7172e0719
performance-optimizer is an agent published in the GitHub repository affaan-m/ECC (290,905 stars, last pushed 2d ago), licensed MIT. It adds 44 tokens to every session and 1,100 once invoked, about $0.0002 per session on Opus 5.5. 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 2026-09-03.
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refactor-cleaner
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