Tools for Claude / Anthropic

MIT source for the reverse-engineer-anything skill - evidence-led native, managed, JavaScript/Electron, packaged, and browser investigations with explicit provider limits

by Jesse Vincent - A strong bundle of core competencies for software engineering, with good coverage of a large portion of the SDLC - from planning, reviewing, testing, debugging... Well written, well organized, and adaptable. The author refers to them as "superpowers", but many of them are just consolidating engineering best practices - which sometimes does feel like a superpower when working wit

Source for 17 Matt Pocock workflow skills - codebase design, TDD, bug diagnosis, triage, PRDs, issues, prototyping, handoff, teaching, and skill-writing guidance (MIT)

by Affaan Mustafa - Top-notch, well-written resources covering "just about everything" from core engineering domains. What's nice about this "everything-" store is most of the resources have significant standalone value and unlike some all-encompassing frameworks, although you can opt in to the author's own specific workflow patterns if you choose, the individual resources offer exemplary patterns

Python / TypeScript - Self-improving AI agent with autonomous skill creation, persistent memory, multi-platform messaging, and subagent delegation

by multica-ai - A drop-in CLAUDE.md distilling four behavioral guidelines for LLM-assisted coding into Claude Code — a low-friction quick win. Karpathy-inspired, derived from Andrej Karpathy's public notes on LLM coding pitfalls and authored by multica-ai

by Anthropic - Anthropic's official repository for Agent Skills — the SKILL.md format, a skill template, and example skills, the same format Claude Code loads natively

Skill that makes coding agents behave like a "lazy senior dev": prefer built-in solutions, avoid new dependencies, and write the minimum code that works. Benchmarked on real Claude Code sessions with ~54% fewer lines, ~20% lower cost, and preserved safety guards — a rare harness-level incentive that fights over-engineering rather than just adding capability

World's largest open-source prompt library. 1000s of prompts for all major models

by Anthropic PBC - The official Anthropic implementation of the Ralph Wiggum technique for iterative, self-referential AI development loops in Claude Code

(132.1k ⭐) - Cross-platform desktop assistant for Claude Code, Codex, OpenCode, OpenClaw, Grok Build, and Hermes Agent

Langchain integrates various providers like Anthropic, AWS, and OpenAI, and offers tools for components such as LLMs, chat models, and data analysis, supporting functionalities from Alpha Vantage to YouTube github | docs

GitHub's open-source toolkit for spec-driven development: spec.md → plan.md → tasks.md artifacts convert natural-language intent into a machine-checkable plan before any code is written, with /specify, /plan, /tasks, and /implement commands that run across Claude Code, Copilot, Codex, and Gemini CLI. The clearest reference implementation of treating spec/plan/task documents — not the prompt — as t

(91.5k ⭐) - An AI SKILL that provide design intelligence for building professional UI/UX multiple platforms

Collection of production LLM applications with source code across RAG, multi-agent, and tool-use patterns. Good reference for how harness primitives combine in real applications

(67.0k ⭐) - AI coding assistant skill (Claude Code, Codex, OpenCode, OpenClaw, Factory Droid, Trae)

by Garry Tan - Garry Tan's (Y Combinator) Claude Code setup and "open source software factory" for managing the development lifecycle end-to-end. Includes a set of agents and in-depth skills/tools along with workflows for advancing a product from ideation to production

Open-source browser agent (Python and TypeScript) whose loop injects serialized DOM state each step, exposes browser actions as registered tools, and runs the same code against a local Chrome or a cloud browser. It has grown from a minimal reference into a full framework (~70k lines of Python across agent, DOM, tools, MCP, and sandbox modules) — study it for production DOM-to-context serialization

by Julius Brussee - A plugin that conserves message tokens by communicating in fragmented "caveman speak" - sort of a clever form of compression. Now accompanied by a whole caveman ecosystem including a memory system, caveman spec kit, and a caveman agent

Production-grade engineering skills for AI coding agents, packaged as 24 reusable skills covering the full development lifecycle from /spec to /ship. The slash-command interface and context-aware auto-activation make it a concrete reference for turning senior-engineering judgment into agent-executable harness artifacts

The AI orchestrator for running Codex, Claude Code, OpenCode, and Pi side-by-side in isolated git worktrees. It turns fleet-of-agents execution into a polished desktop IDE with a mobile companion, making parallel agent harness design accessible beyond shell-scripting teams

Self-hosted platform where agents wake on heartbeats to claim tickets, governed by org charts, budgets, and approval gates.

(82.2k ⭐) - A Claude Code plugin that automatically captures everything Claude does during your coding sessions, compresses it with AI (using Claude's agent-sdk), and injects relevant context back into future sessions

Frontend design taste skill collection covering premium UI generation, redesign audits, GSAP motion, Stitch design systems, minimalist and brutalist visual modes, and full-output enforcement

Multi-platform search CLI for 17 sites including Chinese platforms

The 1st Collaborative AI Design Agent Workspace. Local-first and open source. Create motion, prototypes, websites, apps, dashboards, presentations, images, and videos with your team and AI agents. Share work, exchange feedback, and iterate together in one workspace.

OpenDevin is an open-source initiative aimed at replicating and enhancing the autonomous AI software engineer Devin, focusing on collaboration and complex task execution in software development, emphasizing its relevance to advancing agentic AI technologies github | github profile

by tt-a1i - An Agent Skill for Claude Code that generates interactive architecture, workflow, sequence, data-flow, and lifecycle diagrams as standalone HTML. Typed JSON, local renderers, and delivery checks support source-linked node details, path tracing, themes, and export

Anthropic's official reference MCP server implementations (GitHub, Slack, Postgres, Puppeteer, etc.). The authoritative source for understanding correct MCP server structure before building your own

(59.1k ⭐) - Claude Code skills that turn any codebase into an interactive knowledge graph you can explore, search, and ask questions about (Multi-platform e.g., Codex are supported)

Light and Fast AI Assistant. Support: Web | iOS | MacOS | Android | Linux | Windows

CLI proxy that reduces LLM token consumption by 60-90% on common dev commands. Single Rust binary, zero dependencies

ByteDance's open-source SuperAgent harness built on LangGraph: orchestrates sub-agents with isolated contexts, persistent multi-tier memory, Docker/K8s sandbox execution, and on-demand skill loading for long-horizon tasks that span minutes to hours. A concrete reference for composing supervisor coordination, scoped delegation, and real execution environments into a single deployable harness

Lobe Chat - an open-source, modern-design AI chat framework. Supports Multi AI Providers( OpenAI / Claude 3 / Gemini / Ollama / DeepSeek / Qwen), Knowledge Base (file upload / knowledge management / RAG ), Multi-Modals (Plugins/Artifacts) and Thinking. One-click FREE deployment of your private ChatGPT/ Claude / DeepSeek application

Intelligent routing across multiple LLM providers with load balancing, intelligent fallbacks, rate limiting, and response caching. Achieves 40–60% token cost reduction through smart model routing (cheap models for simple tasks, capable models for complex reasoning). Essential infrastructure for harnesses operating under strict cost budgets where model selection is a per-turn decision

Agent orchestration platform -- deploy multi-agent swarms, coordinate autonomous workflows, distributed swarm intelligence, RAG integration

by shareAI-lab - A really interesting analysis of how coding agents like Claude Code are designed. It attempts to break an agent down into its fundamental parts and reconstruct it with minimal code. Great learning resource. Final product is a rudimentary agent with skills, sub-agents, and a todo-list in roughly a few hundred lines of Python

AI-powered job search orchestrator built on Claude Code. 14-skill pipeline that evaluates jobs, generates ATS-tailored PDFs, and tracks applications. Local-first, MIT

Source for the unsloth-finetuning skill - single-GPU VRAM sizing, LoRA/QLoRA configuration, chat-template and loss-masking correctness, GRPO/DPO post-training, and GGUF/merged export paths (Apache-2.0)

Compresses tool outputs, logs, files, and RAG chunks before they enter the context window, cutting active tokens by 60–95% without changing answers. Ships as a library, proxy, and MCP server — the right drop-in layer for any harness where bulky tool returns are the primary context pressure source

30 curated skills + 832 SaaS automation templates via Composio. Strong on document processing, creative, and business skills

Write videos as HTML and render them to MP4: launch films, explainers, captions, charts and 450+ ready-made blocks, by HeyGen

(54.9k ⭐) - Local code knowledge graph for Claude Code, Codex, Gemini, Cursor, OpenCode, Antigravity, Kiro, and Hermes Agent

World's first open-source, agentic video production system. 12 production pipelines, 100+ tools, 700+ agent skill and production-knowledge files. Turn your AI coding assistant into a full video production studio.

Autonomous coding agent in VS Code with human-in-the-loop approvals; file editing, terminal commands, and browser use. ~59K+ ⭐

Documented system prompts from Anthropic - Claude Fable 5.1, Opus 5.5, Claude Design, Claude Code. OpenAI - ChatGPT GPT-6-Astra, Codex. Google - Gemini 3.8 Flash, 3.1 Pro, Antigravity. xAI - Grok, Grok Bot, Cursor, Kimi and more! Updated regularly.

Agents & Pre-built tools

The job search that runs on your machine. AI job application framework built on Claude Code: evaluate postings, tailor CVs, write cover letters, prep interviews. Fork it and own it.

Comprehensive reference implementation for Claude Code configuration -- skills, subagents, hooks, commands with practical examples. 17,400+ stars

Inspiration for JavaScript Mastery

Research any topic across Reddit, X, YouTube, HN, Polymarket, and the web, ranked by upvotes, likes, and real money instead of editors

by Cathryn Lavery - Another welcome contribution to the domain of making Claude Code output look stylish, this collection of skills produces a variety of editorial diagrams in the form of self-contained HTML + SVG. Although I never thought I'd hear these words together, according to the author: "no Mermaid-slop."

(24.1k ⭐) - A Claude Code skill that removes signs of AI-generated writing from text, making it sound more natural and human

Unified proxy and SDK that routes to 100+ LLM providers behind a single OpenAI-compatible interface, with a Router handling retry/fallback across deployments, per-project cost and rate-limit tracking, and OTEL callback integrations. The right infrastructure layer when your harness needs provider resilience (automatic failover on 429/500 errors), budget guardrails, or the ability to swap models wit

(6.2k ⭐) - A skill that keeps coding-agent answers direct, concise, and easy to scan

(33.3k ⭐) - Marketing skills for Claude Code and AI agents. CRO, copywriting, SEO, analytics, and growth engineering

Agent memory system organized around three explicit operations—retain, recall, and reflect—with semantic, keyword, graph, and temporal retrieval plus an MCP server. The June 2026 release and production usage make it a concrete reference for turning cross-session persistence from passive storage into an active learning layer inside the harness

(51.2k ⭐) - API service that wraps Antigravity, Codex, Claude Code, and Grok Build behind OpenAI-, Gemini-, Claude-, and Codex-compatible endpoints

Curated resources, tools, and workflows specifically for Claude Code users

(943 ⭐) - Cloudflare coding-agent skill for multi-phase security audits with independently verified, machine-readable findings

by K-Dense - "A set of ready-to-use Agent Skills for research, science, engineering, analysis, finance and writing." That's their description - modest, simple. That's how you can tell this is really one of the best skills repos on GitHub. If you've ever thought about getting a PhD... just read all of these documents instead. Also I think it IS an AI agent or something? Awesome

(31.3k ⭐) - Academic Research Skills for Claude Code: research → write → review → revise → finalize

Anthropic's official notebook collection covering orchestrator-worker patterns, parallel tool calling, programmatic tool calling (PTC), context compaction, and Agent SDK examples. The patterns/agents/ directory is the reference implementation of every orchestration pattern described in *Building Effective Agents

Source for Emil Kowalski design engineering skills - UI polish, motion review, animation standards, component craft, and high-taste frontend guidance (MIT)

Obsidian-focused skills for markdown, Bases, JSON Canvas, CLI workflows, and content cleanup

AI pair-programmer harness with an Architect mode that splits planning (one LLM) from coding (another), and git-aware tooling that uses version control as the undo mechanism instead of custom state rollback. The best reference for multi-file editing tool design and planner/coder layer separation

Alibaba's production-grade code review agent combining deterministic pipelines with LLM reasoning: built-in fine-tuned rules catch NPE, thread-safety, and injection vulnerabilities at line-level precision, while the LLM layer handles nuanced design feedback. Demonstrates how hybrid harnesses can outperform purely model-driven or purely static-analysis approaches by assigning each layer the problem

Installable library of 1,400+ agentic skills for Claude Code, Cursor, Codex CLI, Gemini CLI, and more. The largest community-driven skill catalog with an npm installer and role-based bundles — a concrete reference for treating skills as versioned harness artifacts rather than ad-hoc prompts

High-performance code intelligence MCP server that full-indexes repositories into a persistent knowledge graph via tree-sitter AST analysis across 66 languages. Replaces dozens of file-read/grep cycles with sub-millisecond structured queries, cutting active tokens by 120× and turning codebase navigation from a context-pressure problem into a pointer-chasing problem

Background runtime that owns your agents' terminals: sessions survive reboot and reattach from any terminal or SSH, panes are marked working/blocked/idle, and agents themselves spawn panes and prompt each other over a CLI and socket API. One Rust binary.

Self-hosted multi-model chat. All major providers

by luongnv89 - A structured, chapter-based getting-started guide for Claude Code with a self-assessment quiz and a ten-module progressive learning path — slash commands, memory, skills, subagents, MCP, hooks, plugins, and checkpoints — with visual diagrams and copy-paste templates

by Anthropic - Anthropic's official, curated directory of high-quality Claude Code plugins, installable from within Claude Code

OpenAI-compatible proxy that stacks the free tiers of 28 LLM providers (~4B free tokens/month) behind one /v1 endpoint — smart routing, automatic failover, encrypted keys

Sub2API 一站式开源中转服务，让 Claude、Openai 、Gemini、Grok订阅统一接入，支持拼车共享，更高效分摊成本，原生工具无缝使用。

(29.2k ⭐) - Design skill and CLI for building, auditing, and redesigning interfaces with checks for common AI-generated design patterns

Source for 43 security skills covering reverse engineering, binary analysis, offensive assessment orchestration, and threat-intelligence workflows, adapted with English metadata and upstream safety gates (MIT)

Cross-harness plugin marketplace that maintains one source-of-truth plugins/ directory and generates harness-native artifacts for Claude Code, Codex CLI, Cursor, OpenCode, Gemini CLI, and GitHub Copilot. It is the clearest practical example of treating reusable agent capabilities as a portable distribution format rather than ad-hoc prompt files

17 directives blocking the most common LLM coding honesty failures: hallucinated APIs, invented signatures, false-confidence validation, manufactured-urgency capitulation, authority-driven softening, and self-referential comments. Drop the .mdc in .cursor/rules/

(31.1k ⭐) - Reference agents, skills, and data connectors for the financial-services workflows

Arm Cloud Migration Assistant accelerates moving x86 workloads to Arm infrastructure. It scans the repository for architecture assumptions, portability issues, container base image and dependency incompatibilities, and recommends Arm-optimized changes. It can drive multi-arch container builds, validate performance, and guide optimization, enabling smooth cross-platform deployment directly inside G

Claude Code plugin that externalizes multi-agent orchestration as installable skills and staged team pipelines, with cross-provider advisor routing and built-in requirement-clarification interviews. The most widely adopted example of turning a single-agent CLI into a team-ready meta-harness without rewriting the underlying loop

Connect and unify data across various platforms and databases with MindsDB as a single MCP server

Clone any website with one command using AI coding agents

(35.0k ⭐) - Use Claude Code as the foundation for coding infrastructure, allowing you to decide how to interact with the model while enjoying updates from Anthropic

Your AI second brain. Self-hostable. Get answers from the web or your docs. Build custom agents, schedule automations, do deep research. Turn any online or local LLM into your personal, autonomous AI (gpt, claude, gemini, llama, qwen, mistral) github | website

(22.3k ⭐) - Install agent skills onto your coding agents from any git repository

⌥ Coding agent with the IDE wired in. Built by Stencil Labs.

Harness control surface available as web, mobile, and desktop app. Claude Code, Codex, Cursor, Grok Build, OpenCode.

1,000+ agent skills from official dev teams and community. Works with Codex, Claude Code, Gemini CLI, Cursor

(5.9k ⭐) - Turn any technical book PDF into a Claude Code skill — ready to study, reference, and use while you work

Agents are first-class members of shared channels on a Nostr relay you own, with their own keys and audit trails. Claude Code, Codex, Goose.

Draw and edit draw.io diagrams from your project's files on a live browser canvas you can also edit by hand, with version history, undo, AWS, Azure and GCP shape libraries and PNG or SVG export

753 cybersecurity skills across 38 domains: cloud security, pentesting, red teaming, DFIR, malware analysis, threat intel, and more (MITRE ATT&CK mapped)

Official plugin to use Codex from Claude Code for code reviews and task delegation

(20.6k ⭐) - Open source repository of plugins primarily intended for knowledge workers to use in Claude Cowork & Claude Code

Open-source desktop client that runs multiple agent CLIs (Claude Code, Codex, Gemini CLI, Qwen Code) side by side, with multi-session chat, MCP and ACP support, and local file management

(27.9k ⭐) - A collection of skills for AI coding agents. Skills are packaged instructions and scripts that extend agent capabilities

MCP server that intercepts raw tool output before it enters the context window, sandboxing bulky data (Playwright snapshots, GitHub issues, logs) outside the LLM and retrieving only relevant fragments via BM25 when needed. The "think in code" paradigm — replacing ten file-read tool calls with one script execution — is a concrete harness pattern for turning context pressure into a programming probl

CLI tool for configuring and monitoring Claude Code projects and workflows