8 676 development skills from 759 authors. They write and change code. Half of them fit into 1 830 tokens or less — that is what one costs your context window when the agent loads it. 1 213 ship runnable scripts rather than instructions alone. 42 of them cannot work without an MCP server, most often rube. We also found 1 172 copies of these same skills sitting in other people's repositories — counted once here, not 1 172 times.
8 676 unique 759 authors 5 252 updated this month 1 369 from vendors
Creates, updates, or optimizes an AGENTS.md file for a repository with minimal, high-signal instructions covering non-discoverable coding conventions, tooling quirks, workflow preferences, and project-specific rules that agents cannot infer from reading the codebase. Use when setting up agent instructions or Claude configuration for a new repository, when an existing AGENTS.md is too long, generic, or stale, when agents repeatedly make avoidable mistakes, or when repository workflows have changed and the agent configuration needs pruning. Applies a discoverability filter—omitting anything Claude can learn from README, code, config, or directory structure—and a quality gate to verify each line remains accurate and operationally significant.
INVOKE THIS SKILL when building evaluation pipelines for LangSmith. Covers three core components: (1) Creating Evaluators - LLM-as-Judge, custom code; (2) Defining Run Functions - how to capture outputs and trajectories from your agent; (3) Running Evaluations - locally with evaluate() or auto-run via LangSmith. Uses the langsmith CLI tool.
Implement memory-safe programming with RAII, ownership, smart pointers, and resource management across Rust, C++, and C. Use when writing safe systems code, managing resources, or preventing memory bugs.
Aids in writing Mojo code that interoperates with Python using current syntax and conventions. Use this skill in addition to mojo-syntax when writing Mojo code that interacts with Python, calls Python libraries from Mojo, or exposes Mojo types/functions to Python. Also use when the user wants to build Python extension modules in Mojo, wrap Mojo structs for Python consumption, or convert between Python and Mojo types.
NestJS best practices and architecture patterns for building production-ready applications. This skill should be used when writing, reviewing, or refactoring NestJS code to ensure proper patterns for modules, dependency injection, security, and performance.
Build high-performance native modules for Node.js using Rust and N-API via napi-rs. Use when optimizing compute-intensive operations, integrating system libraries, or requiring native performance without blocking the event loop.
Debugs native module crashes, optimizes V8 performance, configures node-gyp builds, writes N-API/node-addon-api bindings, and diagnoses libuv event loop issues in Node.js. Use when working with C++ addons, native modules, binding.gyp, node-gyp errors, segfaults, memory leaks in native code, V8 optimization/deoptimization, libuv thread pool tuning, N-API or NAN bindings, build system failures, or any Node.js internals below the JavaScript layer.
Handles git and GitHub operations using the gh CLI. Use when the user asks about pull requests (PRs), GitHub issues, repo management, branching, merging, rebasing, cherry-picking, merge conflict resolution, commit history cleanup, pre-commit hook debugging, GitHub Actions workflows, or releases. Covers creating and reviewing PRs, watching CI checks, interactive rebasing, branch cleanup, submodule management, and repository archaeology with git log/blame/bisect.
Generate and maintain OpenAPI 3.1 specifications from code, design-first specs, and validation patterns. Use when creating API documentation, generating SDKs, or ensuring API contract compliance.
CLI for querying Prometheus and PromQL-compatible engines (Thanos, Cortex, VictoriaMetrics, Grafana Mimir, Grafana Tempo...) — instant queries, range queries, metric discovery (metrics/labels/meta subcommands), output formats (table/csv/json/graph). Apply when executing PromQL queries, troubleshooting performance issues on a software having observability, investigating latency/error rates/saturation, or analyzing time series data.
Profile and optimize Python code using cProfile, memory profilers, and performance best practices. Use when debugging slow Python code, optimizing bottlenecks, or improving application performance.
Master Rust async programming with Tokio, async traits, error handling, and concurrent patterns. Use when building async Rust applications, implementing concurrent systems, or debugging async code.
| dependsOn, caching, remote cache, the "turbo" CLI, --filter, --affected, CI optimization, environment variables, internal packages, monorepo structure/best practices, and boundaries. monorepo, shares code between apps, runs changed/affected packages, debugs cache, or has apps/packages directories.
Master TypeScript's advanced type system including generics, conditional types, mapped types, template literals, and utility types for building type-safe applications. Use when implementing complex type logic, creating reusable type utilities, or ensuring compile-time type safety in TypeScript projects.
Designs complex generic types, refactors `any` types to strict alternatives, creates type guards and utility types, and resolves TypeScript compiler errors. Use when the user asks about TypeScript (TS) types, generics, type inference, type guards, removing `any` types, strict typing, type errors, `infer`, `extends`, conditional types, mapped types, template literal types, branded/opaque types, or utility types like `Partial`, `Record`, `ReturnType`, and `Awaited`.
Standards for high-performance Declarative UI and State Hoisting. Use whenever writing ANY Jetpack Compose code — @Composable functions, Screen files, LazyColumn, state hoisting, LaunchedEffect, or when someone asks why their Composable recomposes too often. (triggers: **/*Screen.kt, **/*Composable*.kt, **/*Content.kt, @Composable, Modifier, Column, Row, LazyColumn, setContent, recompose, remember, derivedStateOf, LaunchedEffect)
Standards for Coroutines, Flow, and Threading. Use when writing suspend functions, choosing coroutine scopes, switching between StateFlow and SharedFlow, injecting Dispatchers for testability, or debugging threading issues in Android. (triggers: **/*ViewModel.kt, **/*UseCase.kt, **/*Repository.kt, suspend, viewModelScope, lifecycleScope, Flow, coroutine, Dispatcher, DispatcherProvider, GlobalScope)
Standards for Hilt Setup, Scoping, and Modules. Use when setting up Hilt dependency injection, component scoping, or modules in Android. (triggers: **/*Module.kt, **/*Component.kt, @HiltAndroidApp, @Inject, @Provides, @Binds)
Standards for Retrofit, OkHttp, and API Communication. Use when integrating Retrofit, OkHttp, or API clients in Android apps. (triggers: **/*Api.kt, **/*Service.kt, **/*Client.kt, Retrofit, OkHttpClient, @GET, @POST)
Best practices for DI, inject() usage, and providers. Use when configuring Angular dependency injection, using inject(), or defining providers. (triggers: **/*.service.ts, angular inject, providedIn, injection token, provideAppInitializer)
Angular CLI usage, code generation, build configuration, and bundle optimization. Use when creating Angular projects, generating components/services/guards, configuring builds, running tests, or analyzing bundles. (triggers: angular.json, ng generate, ng build, ng serve, ng test, ng add, angular cli, bundle analysis)
REST API conventions — HTTP semantics, status codes, versioning, pagination, and OpenAPI standards applicable to any framework. (triggers: **/*.controller.ts, **/*.router.ts, **/*.routes.ts, **/routes/**, **/controllers/**, **/handlers/**, rest api, endpoint, http method, status code, versioning, pagination, openapi, api design, api contract)
Universal standards for version control, branching, and team collaboration. Use when writing commits, creating branches, merging, or opening pull requests. (triggers: commit, branch, merge, pull-request, git)
Standards for automated service locator setup using injectable and get_it. Use when configuring dependency injection with injectable and get_it in Flutter. (triggers: **/injection.dart, **/locator.dart, GetIt, injectable, singleton, module, lazySingleton, factory)
Universal standards for version control, branching, and team collaboration. Use when writing commits, creating branches, merging, or opening pull requests.
Standards for building HTTP services, REST APIs, and middleware in Golang. Use when building Go HTTP servers, REST APIs, or custom middleware. (triggers: cmd/server/*.go, internal/adapter/handler/**, http server, rest api, gin, echo, middleware)
Standards for structural design, Clean Architecture, and project layout in Golang. Use when structuring Go projects or applying Clean Architecture in Go. (triggers: go.mod, internal/**, architecture, structure, folder layout, clean arch, dependency injection)
Standards for safe concurrent programming using Goroutines, Channels, and Context. Use when implementing concurrency with Goroutines, Channels, or Context in Go. (triggers: goroutine, go keyword, channel, mutex, waitgroup, context, errgroup, race condition)
Standards for application configuration using environment variables and libraries. Use when managing Go application config with environment variables or viper. (triggers: configs/**, cmd/**, configuration, env var, viper, koanf)
Standards for database interaction, connection pooling, and repository patterns in Golang. Use when implementing database access, connection pools, or repositories in Go. (triggers: internal/adapter/repository/**, database, sql, postgres, gorm, sqlc, pgx)
Standards for error wrapping, checking, and definition in Golang. Use when wrapping errors, defining sentinel errors, or handling errors idiomatically in Go. (triggers: fmt.Errorf, errors.Is, errors.As, error wrapping, sentinel error, error handling)
Core idioms, style guides, and best practices for writing idiomatic Go code. Use when writing Go code following official style guides and idiomatic patterns. (triggers: go.mod, golang, go code, idiomatic, gofmt, goimports, iota, golang style)
Standards for structured logging and observability in Golang. Use when adding structured logging or tracing to Go services. (triggers: go.mod, pkg/logger/**, logging, slog, structured logging, zap)
Security standards for Go backend services. Use when implementing input validation, crypto, or SQL injection prevention in Go. (triggers: crypto/rand, argon2, sanitize, jwt, bcrypt, validation, input validation, sql injection)
Go developer toolchain — gopls LSP diagnostics, linting, formatting, and vet. Use when setting up Go tooling, running linters, or integrating gopls with Claude Code. (triggers: gopls, golangci-lint, golangci.yml, go vet, goimports, staticcheck, go tooling, go lint)
Standards for Protocol-based DI, Property Wrappers, and Factory/Needle. Use when configuring dependency injection or factory patterns in iOS. (triggers: **/*.swift, @Injected, Resolver, Container, Swinject, register, resolve)
Standards for URLSession, Alamofire, and API communication. Use when implementing URLSession networking, Alamofire, or API clients in iOS. (triggers: **/*Service.swift, **/*API.swift, **/*Client.swift, URLSession, Alamofire, Moya, URLRequest, URLComponents, Codable)
Core patterns for robust Kotlin code including scope functions and backing properties. Use when writing idiomatic Kotlin, choosing between scope functions (let/apply/run/also/with), encapsulating mutable state with backing properties, or exposing read-only collection interfaces. (triggers: **/*.kt, apply, let, run, also, with, runCatching, backing property, MutableList, internal, private set)
Idiomatic Kotlin 1.9+ standards including null safety, sealed classes, and expression syntax. Use when working with Kotlin null safety, data classes, sealed interfaces, extension functions, or migrating Java code to Kotlin. (triggers: **/*.kt, **/*.kts, val, var, ?., ?:, !!, data class, sealed, when, extension, lazy, lateinit, object)
Modern TypeScript standards for type safety and maintainability. Use when working with types, interfaces, generics, enums, unions, or tsconfig settings.
REST and JSON API standards for modern Laravel backends. Use when designing REST endpoints, API resources, or JSON API responses in Laravel. (triggers: routes/api.php, app/Http/Resources/**/*.php, resource, collection, sanctum, passport, cors)
Response wrapping, pagination, and error standardization. Use when standardizing API response envelopes, pagination, or error formats in NestJS. (triggers: **/*.controller.ts, **/*.dto.ts, ApiResponse, Pagination, TransformInterceptor)
File-system routing, Layouts, and Route Groups. Use when implementing App Router routing, nested layouts, or route groups in Next.js. (triggers: app/**/page.tsx, app/**/layout.tsx, app/**/loading.tsx, App Router, Layout, Route Group, parallel routes)
Scalable project structure using Feature-Sliced Design (FSD). Use when structuring a Next.js project with Feature-Sliced Design architecture. (triggers: src/features/**, src/entities/**, src/widgets/**, FSD, Feature Sliced Design, slices, segments)
The 4 layers of caching in Next.js. Use when configuring request memoization, data cache, full-route cache, or router cache in Next.js. (triggers: **/page.tsx, **/layout.tsx, **/action.ts, unstable_cache, revalidateTag, Router Cache, Data Cache)
Secure, reusable data access patterns with DTOs and Taint checks. Use when building a data access layer with DTOs and server-side taint checking in Next.js. (triggers: **/lib/data.ts, **/services/*.ts, **/dal/**, DAL, Data Access Layer, server-only, DTO)
Fetch API, Caching, and Revalidation strategies. Use when fetching data, configuring cache behavior, or implementing revalidation in Next.js. (triggers: **/*.tsx, **/service.ts, fetch, revalidate, no-store, force-cache)
Best practices for multi-language handling, locale routing, and detection strategies across App and Pages Router. Use when adding i18n, locale routing, or language detection in Next.js. (triggers: middleware.ts, app/[lang]/**, pages/[locale]/**, messages/*.json, next.config.js, i18n, locale, translation, next-intl, react-intl, next-translate)