Everything
Claude Code

Performance optimization for AI agent harnesses

affaan-m/everything-claude-code — 93k stars • Anthropic hackathon winner

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What Is everything-claude-code?

A production-ready plugin ecosystem that transforms AI coding agents from generic assistants into optimized, context-aware, self-improving systems.

The Numbers

93.3KGitHub stars
28Specialized sub-agents
116Skills (domain expertise)
59Slash commands
12Language ecosystems
997+Internal tests passing

Compatible Harnesses

  • Claude Code (primary)
  • Cursor IDE
  • OpenCode
  • Codex CLI
  • Antigravity IDEs

Evolved through 10+ months of intensive daily use. Not theoretical configs — battle-tested patterns.

Repository Architecture

A layered plugin system with clear separation of concerns

commands/59 slash commands for task execution
skills/116 workflow definitions + domain knowledge
agents/28 specialized sub-agents for delegation
hooks/Lifecycle automations (PreToolUse, PostToolUse, Stop)
rules/Always-follow guidelines per language
contexts/Dynamic system prompt injection by mode
scripts/Cross-platform Node.js hook implementations
mcp-configs/MCP server configs (GitHub, Supabase, Vercel...)

Installation & Plugin System

Selective install architecture with manifest-driven state tracking

# Quick install via marketplace
/plugin marketplace add \
  affaan-m/everything-claude-code

/plugin install \
  everything-claude-code@everything-claude-code

# Or clone + selective install
git clone https://github.com/affaan-m/everything-claude-code
./install.sh typescript   # language-specific

# Start using immediately
/everything-claude-code:plan "Build auth system"

Key Design Decisions

  • Manifest-driven — tracks install state for incremental updates
  • Language-scoped — install only what you need
  • Cross-platform — macOS, Linux, Windows (PowerShell)
  • Non-destructive — doesn't override existing configs

v1.9.0 (Mar 2026)

Selective install architecture lets you pick exactly which agents, skills, and rules to install per project.

116 Skills — Domain Expertise on Demand

Workflow definitions and specialized knowledge the agent can invoke

Language & Framework

TypeScriptPythonGo
C++JavaKotlin
SwiftPerlRust
DjangoLaravelSpring Boot

Engineering Practices

  • TDD methodology with verification loops
  • E2E testing (Playwright)
  • Code review patterns
  • Strategic compaction

Infrastructure & Data

  • ClickHouse query optimization
  • PostgreSQL tuning
  • Docker orchestration
  • Database migrations
  • API design patterns

Business & Content

  • Article writing & content engines
  • Investor materials & outreach
  • Market research
  • Documentation generation

Specialized

  • On-device ML (PyTorch)
  • Video processing (VideoDB)
  • MCP server patterns

59 Slash Commands

Quick task execution without context-switching

Planning & Architecture

/plan       # Structured task breakdown
/architect  # System design decisions
/research   # Deep-dive investigation

Development

/tdd         # Test-driven development
/build-fix   # Auto-resolve build errors
/refactor    # Structured refactoring
/dead-code   # Find and remove dead code

Quality & Security

/code-review    # Senior-level review
/security-scan  # Vulnerability analysis
/e2e            # End-to-end test generation

Learning & Evolution

/learn    # Capture mid-session insight
/evolve   # Cluster instincts into skills
/review   # Review learned patterns

Commands are the entry points; they compose skills + agents under the hood to accomplish complex workflows.

28 Specialized Sub-Agents

Delegation architecture for complex multi-step tasks

AgentRole
PlannerTask decomposition & sequencing
ArchitectSystem design & trade-off analysis
Code ReviewerQuality gates & best practices
Build ResolverCompile error diagnosis & fix
Security AnalystVulnerability scanning & remediation
DB OptimizerQuery analysis & index suggestions

Language-Specific Agents (v1.9.0)

  • TypeScript reviewer + build resolver
  • Python / PyTorch reviewer + build resolver
  • Java / Kotlin reviewer + build resolver
  • Go / Rust / Swift specialists

The Context Problem

Each agent runs in its own context window. The iterative retrieval pattern uses progressive refinement to prevent information loss across agent boundaries.

Hooks — Lifecycle Automation

Trigger-based actions at every phase of agent execution

Hook Phases

SessionStart
Load saved context, restore state from SQLite
PreToolUse
Validate tool calls before execution
PostToolUse
Process results, extract patterns
Stop
Final checks before response delivery
SessionEnd
Persist context, save learned patterns

Runtime Controls

# Profile levels
ECC_HOOK_PROFILE=minimal   # light touch
ECC_HOOK_PROFILE=standard  # default
ECC_HOOK_PROFILE=strict    # maximum checks

# Disable specific hooks
ECC_DISABLED_HOOKS=hook-a,hook-b

Observer Reliability (v1.9.0)

Memory explosion fixes, throttling, tail sampling, sandbox access correction, and re-entrancy guards ensure hooks don't degrade performance.

Rules — Always-Follow Guidelines

Language-specific coding standards injected into every prompt

Rules are the guardrails that ensure consistent code quality regardless of which skill or agent is active. They're organized by language and always present in the agent's system prompt.

Supported Languages

TypeScriptStrict types, ESM, error handling
PythonType hints, async patterns, packaging
GoError wrapping, interfaces, testing
SwiftProtocols, Concurrency, memory
RustOwnership, lifetimes, unsafe policy
JavaGenerics, streams, Spring patterns
PHPPSR-12, strict types, Laravel conventions
Perlstrict/warnings, Modern Perl idioms

What Rules Enforce

  • Coding standards — naming, structure, idioms
  • Security mandates — input validation, sanitization
  • Error handling — explicit error types, no swallowing
  • Testing requirements — minimum coverage, edge cases
  • Framework patterns — idiomatic usage, anti-patterns
# Example: TypeScript rule enforcement
# The agent will always:
- Use strict TypeScript (no `any`)
- Prefer interfaces over types
- Handle errors explicitly
- Use ESM imports
- Add JSDoc for public APIs

Contexts — Dynamic Prompt Injection

Different modes activate different system prompt layers

Development Context

Activates code generation rules, build tooling, test patterns. Focuses the agent on shipping code.

Review Context

Shifts to analysis mode: code review checklists, security scanning, performance audit patterns.

Research Context

Enables investigation workflows: web search, documentation parsing, comparison frameworks.

How It Works

Contexts are layered on top of the base system prompt. They don't replace rules — they add mode-specific guidance.

# Context composition:
Base prompt
  + Language rules (always)
  + Active context (mode)
  + Skill knowledge (on demand)
  + Memory/state  (persisted)
  = Final system prompt

This layering keeps the base lean while allowing rich, task-specific knowledge to be injected only when needed.

Memory & Context Persistence

Surviving the session boundary problem

The Problem

AI agents lose all context when a session ends. Every new session starts from scratch — no memory of decisions, patterns, or project state.

The Solution

  • SessionEnd hook — auto-saves context to SQLite
  • SessionStart hook — auto-loads context on resume
  • Strategic compaction — prunes low-value context
  • Pattern extraction — distills sessions into instincts

SQLite State Store

# State persists structured data
# between sessions:

session_context
  - project decisions
  - architecture choices
  - resolved issues

learned_patterns
  - coding preferences
  - error resolution paths
  - project conventions

instincts
  - confidence scores
  - usage frequency
  - evolution history

Continuous Learning — Instinct Evolution

The agent gets smarter with every session

Capture
/learn records a mid-session insight with context
Score
Confidence scoring based on success/failure feedback
Cluster
/evolve groups related instincts into coherent skills
Apply
High-confidence instincts auto-inject into future sessions
# Capture an insight
/learn "This project uses barrel exports
  for all feature modules"

# Review learned patterns
/review

# Evolve instincts into skills
/evolve

# Import/export for sharing
/export-instincts > team-patterns.json
/import-instincts < team-patterns.json

Practical Impact

After a few sessions, the agent knows your naming conventions, preferred patterns, and common error resolutions without being told.

Security — AgentShield

Automated vulnerability scanning for AI-generated code

Why It Matters

AI agents generate code fast but can introduce vulnerabilities: SQL injection, XSS, leaked secrets, insecure defaults. AgentShield catches these before they ship.

Coverage

102Security rules
1,282+Test cases

What It Scans

  • SQL injection & NoSQL injection
  • Cross-site scripting (XSS)
  • Secret/credential leaks
  • Insecure dependencies
  • Missing authentication checks
  • Improper input sanitization
# Run a security scan
/security-scan

# Output example:
CRITICAL SQL injection in user_query()
  Line 42: f"SELECT * FROM users
    WHERE id = {user_input}"
  FIX: Use parameterized queries

HIGH Hardcoded API key detected
  Line 8: api_key = "sk-..."
  FIX: Use environment variables

LOW Missing rate limiting on /api/login
  FIX: Add express-rate-limit middleware

InsAIts Hook (Community)

Community-contributed security hook that integrates with CI/CD pipelines for continuous scanning.

Token Optimization — Doing More with Less

Strategies to minimize cost and maximize context window utilization

Model Selection

Match model capability to task complexity. Don't use a large model for simple refactors.

Full model
Architecture, complex logic
Mid model
Code review, testing
Fast model
Formatting, renames

Optimization Techniques

  • System prompt slimming — remove redundant instructions
  • Background process pruning — kill idle watchers
  • Strategic compaction — auto-detect context bloat
  • Selective skill loading — only inject relevant knowledge
  • Context window awareness — monitor token usage

Key insight: Token optimization isn't just about cost — it's about keeping the important context in the window so the agent doesn't lose track of the task.

Parallelization — Scaling Agent Work

Strategies for concurrent execution across multiple workstreams

Git Worktrees

Run multiple agent instances on separate branches simultaneously using git worktree. Each gets its own working directory.

# Create parallel workstreams
git worktree add ../feature-auth feature/auth
git worktree add ../feature-api feature/api

# Run agents in each worktree
# They share the same repo but
# work on different branches

Cascade Method

Coordinated execution where one agent's output feeds the next:

  1. 1. Planner decomposes the task
  2. 2. Architect designs the solution
  3. 3. Multiple coders implement in parallel
  4. 4. Reviewer validates all branches
  5. 5. Build resolver fixes integration issues

Instance Scaling

For heavy workloads, the system provides guidance on how many parallel instances to run based on task complexity and API rate limits.

MCP Configs — External Tool Integration

Model Context Protocol server configurations for common services

Bundled MCP Servers

GitHubPR review, issue management, Actions
SupabaseDatabase ops, auth, edge functions
VercelDeploy, preview, environment config
RailwayService deploy, logs, scaling

MCP configs give the agent authenticated access to external services without embedding credentials in prompts.

# MCP config structure
# mcp-configs/github.json
{
  "name": "github",
  "transport": "stdio",
  "command": "npx",
  "args": [
    "@modelcontextprotocol/server-github"
  ],
  "env": {
    "GITHUB_TOKEN": "${GITHUB_TOKEN}"
  }
}

MCP is becoming the standard protocol for agent-tool communication. These configs are ready-to-use templates for the most common integrations.

Real-World Configuration Templates

Production-tested setups for common architectures

SaaS: Next.js + Supabase + Stripe

# .claude/config
language: typescript
framework: nextjs
database: supabase
payments: stripe
skills:
  - typescript-strict
  - nextjs-app-router
  - supabase-rls
  - stripe-webhooks

Go Microservices: gRPC + PostgreSQL

language: go
framework: grpc
database: postgresql
skills:
  - go-error-handling
  - grpc-protobuf
  - postgres-migrations

Django REST API: DRF + Celery

language: python
framework: django
async: celery
skills:
  - django-drf
  - celery-tasks
  - python-typing

Rust Service: Axum + SQLx

language: rust
framework: axum
database: postgresql
skills:
  - rust-ownership
  - axum-handlers
  - sqlx-queries

Templates are starting points. The selective installer lets you mix and match skills from different templates.

Package Manager Auto-Detection

Cross-platform intelligence for the right tool in every project

Detection Priority

1. ENV var
CLAUDE_PACKAGE_MANAGER overrides everything
2. Project config
.claude/package-manager.json
3. package.json
packageManager field (corepack)
4. Lock file
package-lock.json, yarn.lock, pnpm-lock.yaml, bun.lockb
5. Global config
~/.claude/package-manager.json
6. Fallback
First available: npm, pnpm, yarn, bun

Why This Matters

AI agents frequently generate wrong install commands (npm install in a pnpm project). This detection ensures correct commands every time.

# Project-level config
# .claude/package-manager.json
{
  "manager": "pnpm",
  "version": "9.x"
}

# The agent then uses:
pnpm add express     # not npm install
pnpm run build       # not npm run
pnpm exec tsc        # not npx

Verification — Trust but Check

Evaluation approaches for AI-generated code

Checkpoint vs. Continuous

Checkpoint Evaluation

Run tests at key milestones. Lower overhead, but problems compound between checks.

Continuous Evaluation

Validate after every tool call via PostToolUse hooks. Higher overhead, catches issues immediately.

Grader Types

  • Type checker — does it compile?
  • Unit tests — does it pass existing tests?
  • Linter — does it follow style rules?
  • Security scan — is it safe?
  • LLM grader — does it match intent?

Pass@k Metrics

Generate k solutions and measure what fraction passes all graders. Useful for benchmarking agent configurations against each other.

Project Configuration In Practice

How CLAUDE.md ties it all together

# CLAUDE.md - your project's brain
# This file is read by the agent at
# every session start.

# Project: E-commerce Platform

## Stack
- Next.js 15 (App Router)
- Supabase (Auth + DB + Storage)
- Stripe (Payments)
- Resend (Email)

## Conventions
- All components in src/components/
- Server actions in src/actions/
- Always use RLS policies
- Never use any type

## Active Skills
- nextjs-app-router
- supabase-rls
- stripe-webhooks
- typescript-strict

The Composition

When you run a command like /plan "add subscription billing", the system composes:

  1. 1. CLAUDE.md context (always loaded)
  2. 2. TypeScript rules (language match)
  3. 3. Stripe skill (relevant to task)
  4. 4. Planner agent (command delegation)
  5. 5. Persisted memory (past decisions)

This is the core insight: the plugin doesn't replace the agent's intelligence — it gives it the right context at the right time.

Community & Ecosystem

A global open-source effort

By the Numbers

93.3KGitHub stars
12.2KForks
150+GitHub App installs

Translations

  • Korean translation (community)
  • Chinese translation (community)

Notable Contributions

  • InsAIts — security hook for CI/CD
  • Biome optimization — faster linting rules
  • VideoDB integration — video processing skills
  • PowerShell installer — Windows support
  • Bun/Next.js toolchains — modern runtime support

Anthropic Hackathon Winner

The project originated at an Anthropic hackathon and has since grown into one of the most-starred developer tools repositories on GitHub.

v1.9.0 — March 2026 Release

Major architecture and language expansion

Selective Install

  • Manifest-driven installer
  • Tracks installation state
  • Incremental updates (no full reinstall)

Language Expansion

  • 6 new agents (TS, PyTorch, Java, Kotlin)
  • Total: 10 language ecosystems covered
  • Each gets reviewer + build resolver

Session Infrastructure

  • SQLite state store for persistence
  • Session adapters for structured recording
  • Skill evolution foundation

Observer Reliability

  • Memory explosion fixes
  • Throttling + tail sampling
  • Sandbox access correction
  • Re-entrancy guards

New Skills

  • PyTorch patterns, Bun/Next.js toolchains
  • 8 operational domain skills
  • MCP server patterns

CLAUDE.md Best Practices

The single most important file for agent performance

What to Include

  • Project structure — where things live
  • Tech stack — exact versions and tools
  • Conventions — naming, folder structure, patterns
  • Active skills — which plugins to load
  • Forbidden actions — what NOT to do

What to Avoid

  • Verbose prose (wastes tokens)
  • Obvious instructions ("write clean code")
  • Credentials or secrets
  • Long code examples (link to files instead)
# Lean, high-signal CLAUDE.md

# MyApp
Stack: Next.js 15, Supabase, TypeScript
Style: Biome (not ESLint)
Test: Vitest + Playwright

## Rules
- NO any types
- NO default exports
- Server components by default
- All DB access via Supabase RLS

## Structure
src/app/      # Routes
src/components/ # UI
src/lib/      # Shared utils
src/actions/  # Server actions
supabase/     # Migrations

Rule of thumb: If you'd tell a new team member on day one, put it in CLAUDE.md. Everything else goes in skills or rules.

Before & After — The Difference

Same agent, same task, different configuration

Without everything-claude-code

  • Generic code, no project awareness
  • Wrong package manager commands
  • No security scanning
  • Forgets decisions between sessions
  • One-size-fits-all approach
  • Manual context re-loading
  • No verification pipeline

With everything-claude-code

  • Project-aware, convention-following code
  • Auto-detected package manager
  • AgentShield scans every PR
  • Persistent memory across sessions
  • Language-specific expertise loaded
  • Auto-context from hooks + skills
  • TDD + type check + lint pipeline

The plugin transforms the agent from a generic code generator into a project-native team member.

Competitive Landscape

How it compares to alternatives

Feature everything-claude-code Custom CLAUDE.md IDE Plugins
Skills library 116 skills Manual Limited
Sub-agent delegation 28 agents None None
Session persistence SQLite + hooks None Varies
Security scanning AgentShield (102 rules) Manual Basic
Continuous learning Instinct evolution None None
Multi-harness support 5 platforms 1 platform 1 platform
Community size 93K stars N/A Varies

Getting Started Roadmap

From zero to optimized in four steps

Step 1: Install
Clone the repo or use plugin marketplace. Run the installer with your primary language.
./install.sh typescript
Step 2: Configure CLAUDE.md
Add your project stack, conventions, and active skills. Start lean and expand.
Step 3: Use Commands
Start with /plan, /tdd, and /code-review. Let the agent learn your patterns.
Step 4: Evolve
Use /learn to capture insights. Run /evolve periodically to cluster patterns into skills.

Key Takeaways

Agent performance is a system problem

Raw model capability matters less than the system around it: context, memory, tools, and verification.

Context is everything

The right knowledge at the right time beats a bigger model with no context. Skills, rules, and memory make this possible.

Agents should learn

Continuous learning with instinct evolution means the system improves with use, not just with updates.

Security can't be optional

AI-generated code moves fast. Automated security scanning is the only way to keep up without slowing down.

Open source scales

93K stars, 12K forks, translations in multiple languages. The best agent configs come from community iteration.

Start small, grow organically

You don't need all 116 skills. Start with CLAUDE.md + a few commands. Add skills as your needs grow.

"Not just configs.
A complete system."

93k stars • 28 agents • 116 skills • 59 commands • 12 languages

The performance optimization system for AI agent harnesses.
From an Anthropic hackathon winner.

github.com/affaan-m/everything-claude-code

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