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Skills, MCP servers, prompts, assistants and connectors. Every listing shows its author, version and the permissions it needs.
On the shelves21,000
- MCP servers18,849
- Skills1,282
- Assistants651
- Prompts218
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Coding
mattpocock 281kTest-Driven DevelopmentTest-driven development. Use when the user wants to build features or fix bugs test-first, mentions "red-green-refactor", or wants integration tests.SkillNo codeCoding- mattpocock 281kScaffold ExercisesCreate exercise directory structures with sections, problems, solutions, and explainers that pass linting. Use when user wants to scaffold exercises, create exercise stubs, or set up a new course section.SkillNo codeEducationCoding
addyosmani 103kTest-Driven DevelopmentDrives development with tests using the red-green-refactor loop. Use when implementing any logic, fixing any bug, or changing any behavior. Use when you need to prove that code works, when a bug report arrives, or when you're about to modify existing functionality.SkillNo codeCoding
obra 297kSystematic DebuggingUse when encountering any bug, test failure, or unexpected behavior, before proposing fixesSkillNode.jsCoding
alirezarezvani 28kNamed-Persona Adversarial ReviewCode review through the lens of real engineers' documented philosophies (Torvalds, Thompson, Carmack, Kent Beck, Jobs, Cagan). Complements abstract-role adversarial review with named, sourced perspectives. Use when automated review findings feel generic, when a PR has architectural or UX impact, or when the author wants pre-submit hardening beyond standard checks.SkillNo codeDesignCoding- obra 297kRequesting Code ReviewUse when completing tasks, implementing major features, or before merging to verify work meets requirementsSkillNo codeCoding
- obra 297kCode Review ReceptionUse when receiving code review feedback, before implementing suggestions, especially if feedback seems unclear or technically questionable - requires technical rigor and verification, not performative agreement or blind implementationSkillNo codeCoding
- addyosmani 103kCode SimplificationSimplifies code for clarity. Use when refactoring code for clarity without changing behavior. Use when code works but is harder to read, maintain, or extend than it should be. Use when reviewing code that has accumulated unnecessary complexity.SkillNo codeCoding
- mattpocock 281kcode-reviewReview the changes since a fixed point (commit, branch, tag, or merge-base) along two axes: Standards (does the code follow this repo's documented coding standards?) and Spec (does the code match what the originating issue/spec asked for?). Runs both reviews in parallel sub-agents and reports them side by side. Use when the user wants to review a branch, a PR, work-in-progress changes, or asks to "review since X".SkillNo codeCoding
- addyosmani 103kDebugging and Error RecoveryGuides systematic root-cause debugging. Use when tests fail, builds break, something that worked yesterday broke, behavior doesn't match expectations, or you encounter any unexpected error. Use when you need to figure out what broke and why — a systematic approach to finding and fixing the root cause rather than guessing.SkillNo codeCoding
vercel-labs 32kReact Composition PatternsReact composition patterns that scale. Use when refactoring components with boolean prop proliferation, building flexible component libraries, or designing reusable APIs. Triggers on tasks involving compound components, render props, context providers, or component architecture. Includes React 19 API changes.SkillNo codeCloudFrontendCoding- addyosmani 103kBrowser Testing with DevToolsTests in real browsers via Chrome DevTools MCP. Use when building or debugging anything that runs in a browser. Use when you need to inspect the DOM, capture console errors, analyze network requests, profile performance, or verify visual output with real runtime data. Requires the chrome-devtools MCP server to be configured.SkillMedium riskNo codeBrowser automationTestingCoding
openai 28kSecurity Best PracticesPerform language and framework specific security best-practice reviews and suggest improvements. Trigger only when the user explicitly requests security best practices guidance, a security review/report, or secure-by-default coding help. Trigger only for supported languages (python, javascript/typescript, go). Do not trigger for general code review, debugging, or non-security tasks.SkillNo codeSecurityCoding- alirezarezvani 28kTech Debt TrackerScan codebases for technical debt, score severity, track trends, and generate prioritized remediation plans. Use when users mention tech debt, code quality, refactoring priority, debt scoring, cleanup sprints, or code health assessment. Also use for legacy code modernization planning and maintenance cost estimation.SkillPythonHealthCoding
- addyosmani 103kCode Review and QualityConducts multi-axis code review. Use before merging any change. Use when reviewing code written by yourself, another agent, or a human. Use when you need to assess code quality across multiple dimensions before it enters the main branch. Use when asked to review a diff or a pull request, even when the diff is pasted inline.SkillNo codeGit and GitHubCoding
- openai 28kPlaywright Interactive SkillPersistent browser and Electron interaction through `js_repl` for fast iterative UI debugging.SkillNo codeBrowser automationCoding
trailofbits 7.4klibfuzzerSets up and runs libFuzzer, the coverage-guided fuzzer built into LLVM, on C/C++ code that compiles with Clang. Covers harness structure, -fsanitize=fuzzer builds, corpus and dictionary management, sanitizer integration, and campaign triage. Use when writing or debugging an LLVMFuzzerTestOneInput harness, starting fuzzing on a C/C++ library, choosing between libFuzzer and AFL++, or working out why a libFuzzer run finds nothing.SkillNo codeWritingCoding
wshobson 40kTemporal Python Testing StrategiesTest Temporal workflows with pytest, time-skipping, and mocking strategies. Covers unit testing, integration testing, replay testing, and local development setup. Use when implementing Temporal workflow tests or debugging test failures.SkillNo codeTestingCoding- openai 28kThreat Model Source Code RepoRepository-grounded threat modeling that enumerates trust boundaries, assets, attacker capabilities, abuse paths, and mitigations, and writes a concise Markdown threat model. Trigger only when the user explicitly asks to threat model a codebase or path, enumerate threats/abuse paths, or perform AppSec threat modeling. Do not trigger for general architecture summaries, code review, or non-security design work.SkillNo codeDocumentsSecurityCoding
- openai 28kChatGPT AppsBuild, scaffold, refactor, and troubleshoot ChatGPT Apps SDK applications that combine an MCP server and widget UI. Use when Codex needs to design tools, register UI resources, wire the MCP Apps bridge or ChatGPT compatibility APIs, apply Apps SDK metadata or CSP or domain settings, or produce a docs-aligned project scaffold. Prefer a docs-first workflow by invoking the openai-docs skill or OpenAI developer docs MCP tools before generating code.SkillNode.jsCodingAI models
huggingface 11kHugging Face SpacesBuild, deploy, and maintain applications on Hugging Face Spaces — Gradio / Docker / Static SDKs, ZeroGPU and dedicated hardware, model loading, debugging, buckets, inference providers, community grants. Use whenever the user asks to create or host an app on Hugging Face, port code onto ZeroGPU, fix a Space that won't build or run, or otherwise work with `hf spaces …`, `@spaces.GPU`, Space README frontmatter, or the `spaces` Python package.SkillNo codeDevOpsCodingAI models- wshobson 40kSQL Optimization PatternsMaster SQL query optimization, indexing strategies, and EXPLAIN analysis to dramatically improve database performance and eliminate slow queries. Use when debugging slow queries, designing database schemas, or optimizing application performance.SkillNo codeDatabasesCoding
- openai 28kPlaywright CLI SkillUse when the task requires automating a real browser from the terminal (navigation, form filling, snapshots, screenshots, data extraction, UI-flow debugging) via `playwright-cli` or the bundled wrapper script.SkillShellBrowser automationCoding
- huggingface 11kTRLPost-train LLMs with TRL (Transformers Reinforcement Learning) — SFT, DPO, GRPO, KTO, and reward-model training. Use when writing or debugging training code with the TRL Python API or the trl CLI.SkillNo codeWritingEducationCoding