Development Claude Skills
8 673 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 1 239 copies of these same skills sitting in other people's repositories — counted once here, not 1 239 times.
8 673 unique 759 authors 10 updated this month 1 368 from vendors
Comprehensive RESTful API testing patterns covering HTTP methods, status codes, request/response validation, authentication, error handling, and contract testing.
Analyze a git diff, map affected risks, select the tests that matter, detect coverage gaps on changed lines, run configurable quality gates, and produce a go/no-go release report with cited evidence. Recommends only; never merges or deploys.
API endpoint fuzzing for discovering unexpected behaviors, crashes, and security vulnerabilities through malformed requests, boundary values, and protocol violations.
Automated detection of breaking API changes including response format changes, removed endpoints, type changes, and deprecation enforcement.
Validate API responses against OpenAPI/Swagger specifications, JSON Schema definitions, and consumer-driven contracts to prevent breaking changes
Comprehensive RESTful API testing patterns covering HTTP methods, status codes, request/response validation, authentication, error handling, and contract testing.
Testing library backward compatibility including public API surface verification, semver compliance, TypeScript type compatibility, and migration path validation.
Teach agents to build synthetic monitoring as code with Checkly, including Playwright browser checks, API checks, alerting, and CI deploy workflows.
Advanced security analysis using GitHub CodeQL to find zero-day vulnerabilities, injection flaws, and security anti-patterns in source code.
Generate consumer-driven contract tests using Pact framework to verify API provider-consumer compatibility and prevent integration breaking changes
Automated scanning of project dependencies for known vulnerabilities using tools like npm audit, Snyk, and Dependabot patterns.
End-to-end testing for React Native apps using Detox with gray-box testing, synchronization, device simulation, and CI integration.
Validate error boundary implementations in React and other frameworks ensuring graceful degradation, proper fallback UI rendering, and error recovery flows
Debug and fix failing GitHub PR checks by inspecting GitHub Actions logs, summarizing failure context, drafting fix plans, and implementing fixes after approval.
Mock Service Worker v2 patterns - http and graphql request handlers, setupServer for Node test runs, setupWorker for the browser, per-test handler overrides, and strict unhandled-request policies.
Next.js application testing covering Server Components, App Router, API routes, middleware, dynamic routes, and SSR/SSG testing patterns.
Teach agents to run Nuclei DAST and API security scans in CI, write templates, and gate builds on actionable findings.
Grade LLM and agent traces with OpenAI Evals - build datasets, configure string/python/model graders, run eval suites, and gate agent behavior changes in CI.
Comprehensive Python unittest skill covering TestCase patterns, assertion methods, mocking with unittest.mock, subtests, fixtures, and test organization for robust Python application testing.
Component testing using React Testing Library with user-centric queries, accessibility-focused selectors, and integration testing patterns.
Production-grade REST API automation framework with REST Assured, POJO serialization using GSON, PayloadManager pattern, E2E integration workflows with TestNG ITestContext, and Allure reporting.
Expert-level Robot Framework testing skill covering keyword-driven syntax, SeleniumLibrary, RequestsLibrary, custom Python keywords, data-driven testing, resource files, and parallel execution with Pabot.
Rust testing with built-in test framework, integration tests, doc tests, property-based testing with proptest, and cargo test configuration.
Automated detection and prevention of leaked secrets, API keys, passwords, and tokens in code using tools like gitleaks, trufflehog, and pre-commit hooks.
Perform language and framework specific security best-practice reviews, vulnerability detection, and secure-by-default coding guidance for Python, JavaScript/TypeScript, and Go applications.
Analyze git repositories to build security ownership topology, compute bus factor for sensitive code, detect orphaned security-critical files, and export ownership graphs for visualization.
Static application security testing using Semgrep for finding vulnerabilities, code smells, and enforcing security policies across codebases.
API simulation and service virtualization with WireMock for HTTP stubbing, request matching, stateful behavior, and fault injection testing.
Expert guidance for working with Dagster and the dg CLI. ALWAYS use before doing any task that requires knowledge specific to Dagster, or that references assets, materialization, components, data tools or data pipelines. Common tasks may include creating a new project, adding new definitions, understanding the current project structure, answering general questions about the codebase (finding asset, schedule, sensor, component or job definitions), debugging issues, or providing deep information about a specific Dagster concept.
Opinionated production Python standards with automatic version detection (3.10-3.13). Use when writing, reviewing, or refactoring Python in repos that want modern type syntax, explicit condition checks where practical, pathlib operations, interface guidance, and pragmatic production patterns.
Cross-driver GUI actuation for CAE solvers running under sim-cli. Use to click buttons, fill fields, dismiss dialogs, and capture window screenshots against GUI-capable driver windows through `sim exec`.
Cross-solver operating discipline for sim-cli workflows — tool choice, input classification, acceptance semantics, and escalation rules that apply across solvers. Use alongside the solver's own plugin skill, which is self-contained for solver-specific work; this skill carries only the shared rules.
Create, maintain, and troubleshoot APM (Agent Package Manager) manifests for distributing GitHub Copilot skills, agents, and MCP servers. USE FOR: creating apm.yml root manifests; creating packages/* sub-manifests; bundling MCP server config into a package; installing packages from a GitHub repo; troubleshooting APM install errors (missing .vscode/mcp.json, Codex CLI warnings, cached installs). DO NOT USE FOR: general GitHub Copilot customization questions; creating SKILL.md files (use skill-creator); writing MCP server code.
>- Bumps every @x402/* package (the optional peer dependencies in the CDP TypeScript SDK, the pinned dev dependencies used to test the SDK against x402, and the dependencies in every TypeScript x402 example) to the latest lockstep-released version, then verifies the SDK and all examples still build, lint, format, and typecheck. Use when the user asks to bump, update, or sync x402 (or @x402) dependencies/peer dependencies in cdp-sdk, or when a new x402 release needs to be picked up across the repo.
> Use when adding hypermedia links to REST responses, building self-describing APIs, or implementing Spring HATEOAS. Use when you see EntityModel, CollectionModel, or RepresentationModel in the project.
> Use when working in a multi-module Maven project. Covers parent POM conventions, shared dependency management, inter-module rules, and build ordering.
> Use when the project follows hexagonal (ports & adapters) architecture. Prevents domain code from depending on Spring or JPA. Use when you see packages like domain/, application/, infrastructure/, or adapters/ in the project structure.
> Use when building MCP (Model Context Protocol) servers in Java/Spring Boot. Covers tool registration, resource exposure, prompt templates, and production deployment using the official MCP Java SDK. Use when user mentions MCP, AI agent integration, or tool calling.
> Use when building batch jobs, ETL pipelines, scheduled imports/exports, or any chunk-oriented bulk processing with Spring Batch. Covers the Spring Batch 5 / Boot 3 builder API, restartability and idempotent job parameters, reader/writer thread-safety, fault tolerance, and chunk transaction boundaries.
> Use when generating REST controllers, response wrappers, DTOs, error handlers, or any HTTP-facing code. Defines response envelope, HTTP status mapping, pagination, and versioning.
> Use when the project follows hexagonal (ports & adapters) architecture. Prevents domain code from depending on Spring or JPA. Use when you see packages like domain/, application/, infrastructure/, or adapters/ in the project structure.
> Use when working in a multi-module Maven project. Covers parent POM conventions, shared dependency management, inter-module rules, build ordering, and Spring Boot 4 modular starter selection.
> Use when building MCP (Model Context Protocol) servers in Java/Spring Boot. Covers tool registration, resource exposure, prompt templates, and production deployment using the official MCP Java SDK. Use when user mentions MCP, AI agent integration, or tool calling.
> Use when implementing error handling, exception mappers, or error response formatting. Enforces RFC 9457 (Problem Details for HTTP APIs) using Spring's built-in ProblemDetail.
> Use when generating REST controllers, response wrappers, DTOs, error handlers, or any HTTP-facing code. Defines response envelope, HTTP status mapping, pagination, and API versioning (including Spring Boot 4's native version routing).
> Use when building batch jobs, ETL pipelines, scheduled imports/exports, or any chunk-oriented bulk processing with Spring Batch. Covers the Spring Batch 6 / Boot 4 builder API, resourceless vs JDBC job repositories, restartability and idempotent job parameters, reader/writer thread-safety, fault tolerance, and chunk transaction boundaries.
> Initialize or update CLAUDE.md coding standards for any project by auto-detecting tech stack and assembling rules from the claude-rules template library. Use when user says "init rules", "初始化规范", "生成 CLAUDE.md", or wants to set up coding standards.
Read-only investigation and analysis of GitHub issues for Shopify/shopify-app-template-react-router. Fetches issue details via gh CLI, searches for duplicates, examines the template's code for relevant context, applies version-based maintenance policy classification, and produces a structured investigation report. Use when a GitHub issue URL is provided or when asked to analyze or triage an issue.