Development Claude Skills
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
> MANDATORY for static requests to find, identify, or list untested source files or modules, sources without tests, source-to-test pairing, test-gap worklists, or suggested test locations. Invoke even for a tiny package; do not substitute manual globbing. Uses Roslyn for C#/.NET and tree-sitter for Python, TS/JS, Go, grading existing tests.
> Generate wrapper interfaces and DI registration for hard-to-test static dependencies in C#, when the abstraction does NOT exist yet. Produces IFileSystem, IEnvironmentProvider, IConsole, IProcessRunner wrappers, or guides first-time adoption of TimeProvider and IHttpClientFactory. With no DI container, produces the ambient context seam instead. make a static or a class testable, create abstraction for File.*, generate DI registration, adopt TimeProvider when it is not registered yet, IHttpClientFactory setup, testability wrapper, how to make statics injectable, adopt System.IO.Abstractions, make code testable without adding a DI framework. call sites or replacing existing DateTime.*/File.* usages once the wrapper is created or already registered in DI (use migrate-static-to-wrapper), general interface design.
> Replace existing static dependency call sites with a wrapper or built-in abstraction that already exists or is registered in DI, across a bounded scope (file, project, namespace). constructor parameter, migrate static call sites to a wrapper already in DI, bulk replace File.* with IFileSystem, scoped migration of statics in only certain files, update unit tests to a fake time source, make an existing static or utility class testable by adding an ambient TimeProvider/IFileSystem seam while every current call site keeps compiling, behavior-preserving time refactors that must keep the same DateTimeKind. brand-new wrapper interface that does not exist yet (use generate-testability-wrappers), migrating between test frameworks.
> Recommend or run the exact `dotnet test` command. ALWAYS use when the user asks to run, filter, or troubleshoot .NET tests or wants the precise command, flags, or argument order — the right syntax depends on the test platform (VSTest vs Microsoft.Testing.Platform) and SDK version and is specific class, category, or trait) via filters; a single framework in a multi-TFM project (`--framework`); TRX reports; crash or hang dumps; whether MTP args need the `--` separator (SDK 8/9) or pass directly (SDK 10+); diagnosing why `dotnet test` fails or uses wrong argument syntax. Detects the platform (VSTest vs MTP) and framework (MSTest/xUnit/NUnit/TUnit), then picks the matching command and filter flag (--filter, --filter-class, --filter-trait, --filter-query, code-testing-agent), iterating on failing tests without rebuilding (use mtp-hot-reload), CI/CD config, or debugging test logic.
Performs pseudo-mutation analysis on production code in any language to find gaps in existing tests. Use when the user asks to find weak or shallow tests, discover untested edge cases, or check whether tests would catch a bug — e.g. \"would my tests catch it if someone changed the code\", \"would a subtle logic or boundary change slip past the current tests\", \"are my tests strong enough to catch a subtle bug\". Evaluates test effectiveness through mutation-style reasoning: analyzes mutation points (boundaries, boolean flips, null returns, exception removal, arithmetic changes) and checks whether tests would detect each. Polyglot: .NET, Python, TS/JS, Java, Go, Ruby, Rust, Swift, Kotlin, PowerShell, C++. DO NOT USE FOR: writing new tests (use code-testing-agent, or writing-mstest-tests for MSTest), detecting anti-patterns (use test-anti-patterns), measuring assertion diversity (use assertion-quality), or running actual mutation testing tools (Stryker, mutmut, PIT, cargo-mutants).
> Migrate a .NET 10 project or solution to .NET 11 and resolve all breaking changes. This is a MIGRATION skill — use it when upgrading from .NET 10 to .NET 11, NOT for writing new programs. after updating the .NET 11 SDK, resolving source-breaking and behavioral changes in .NET 11 runtime, C# 15 compiler, and EF Core 11, adapting to updated minimum hardware requirements (x86-64-v2, Arm64 LSE), and updating CI/CD pipelines and Dockerfiles for .NET 11. greenfield .NET 11 projects, or cosmetic modernization unrelated to the upgrade.
> Migrate a .NET 8 project to .NET 9 and resolve all breaking changes. after updating the .NET 9 SDK, resolving behavioral changes in .NET 9 / C# 13 / ASP.NET Core 9 / EF Core 9, replacing BinaryFormatter (now always throws), resolving SYSLIB0054-SYSLIB0057, adapting to params span overload resolution, fixing C# 13 compiler changes, updating HttpClientFactory for SocketsHttpHandler, and resolving EF Core 9 migration/Cosmos DB changes. greenfield .NET 9 projects, or cosmetic modernization unrelated to the upgrade.
> Migrate a .NET 9 project or solution to .NET 10 and resolve all breaking changes. after updating the .NET 10 SDK, resolving source and behavioral changes in .NET 10 / C# 14 / ASP.NET Core 10 / EF Core 10, updating Dockerfiles for Debian-to-Ubuntu base images, resolving obsoletion warnings (SYSLIB0058-SYSLIB0062), adapting to SDK/NuGet changes (NU1510, PrunePackageReference), migrating System.Linq.Async to built-in AsyncEnumerable, fixing OpenApi v2 API changes, cryptography renames, and C# 14 compiler changes (field keyword, extension keyword, span overloads). (use migrate-dotnet8-to-dotnet9 first), greenfield .NET 10 projects, or cosmetic modernization. aspnet-core, efcore, cryptography, extensions-hosting, serialization-networking, winforms-wpf, containers-interop (selective).
> Enable nullable reference types in a C# project and systematically resolve all warnings. fixing CS8602/CS8618/CS86xx warnings, annotating APIs for nullability, cleaning up null-forgiving operators, upgrading dependencies with new nullable annotations. suppressions), fixing a handful of nullable warnings in code that already has NRTs enabled, suppressing warnings without fixing them, C# 7.3 or earlier projects.
> Guides migration of .NET Framework Thread.Abort usage to cooperative cancellation in modern .NET. replacing Thread.ResetAbort, replacing Thread.Interrupt for thread termination, resolving PlatformNotSupportedException or SYSLIB0006 after retargeting to .NET 6+, migrating ASP.NET Response.End or Response.Redirect(url, true) which internally call Thread.Abort. without any abort, interrupt, or ThreadAbortException usage — these APIs work identically in modern .NET and need no migration. Also not for projects staying on .NET Framework, or Thread.Abort usage inside third-party libraries you do not control.
> Install a .NET SDK locally for safe preview testing, specific-version pinning, or reproducible team setups — without modifying the system-wide installation. or other workloads on a preview, updating or replacing an existing local SDK, creating reproducible team/CI install scripts, configuring global.json paths. installs, or projects not using SDK-style commands.
Review code that performs git or gh operations against repository checkouts in gh-aw, checking that the right credentials are available at the right time and that sparseness, shallowness and credential-free factors are properly considered.
Author, validate, and debug canvas extensions that the agent can open in the GitHub Copilot app's side panel. Use when creating, reviewing, or troubleshooting a canvas extension — including its actions, inputs, rendered content, and the surrounding extension wiring (tools, hooks, lifecycle).
Release management, changeset workflow, firewall log parsing, breaking CLI change rules, and Go module summaries for gh-aw.
Code organization patterns, file structure guidelines, WASM build variants, and string processing conventions for gh-aw Go code.
Query GitHub issues with jq filtering and reusable selectors.
List GitHub repository labels with per_page pagination support.
Query GitHub discussions with jq filtering and reusable selectors.
Practical tips for reviewing and improving Copilot agent PRs.
Query GitHub pull requests with jq filtering and reusable selectors.
List GitHub Actions workflows with per_page pagination support.
Write robust JavaScript for GitHub Actions github-script steps.
GitHub Agentic Workflows (`gh-aw`) is a GitHub CLI extension for writing Agentic Workflows in markdown and compiling them to GitHub Actions.
Write clear GitHub Actions step summaries with progressive disclosure.
Build ExecuTorch from source — Python package, C++ runtime, runners, cross-compilation, and backend-specific builds. Use when compiling anything in the ExecuTorch repo, diagnosing build failures, or setting up platform-specific builds.
用于查找代码示例、开源项目、GitHub Issue、技术问答、开发者讨论、HuggingFace 模型/数据集/Space。
Use when researching China market, industry, macro, trade, procurement, listed-company disclosure, regulation, IP, healthcare, logistics, energy, environment, or industrial-operation information using free official sources with no registration, no API key, and no cryptocurrency data.
搜索社区、社媒、新闻热点、百科趋势、开发者生态和技术讨论时使用。
Cherry-pick a merged main-branch PR onto a MsQuic release branch (release/X.Y).
Comprehensive toolkit for product managers including RICE prioritization, customer interview analysis, PRD templates, discovery frameworks, and go-to-market strategies. Use for feature prioritization, user research synthesis, requirement documentation, and product strategy development.
将任意网页转换为桌面应用，支持 macOS/Windows/Linux 三大平台。使用 Rust + Tauri 技术栈，生成的应用体积小（约 5MB）、性能高。支持自定义图标、窗口大小、快捷键等丰富配置。
Create and manage Git worktrees for parallel development workflows. Use when multiple self-contained issues should NOT be fixed in a single branch, when human-Copilot iteration requires isolated environments with separate chat history and commits, or when parallel work items need independent build/test results. Triggers on requests involving branch isolation, work item separation, parallel development, or avoiding messy branch switching.
Generate comprehensive GitHub Feature Area Status reports for the Windows App SDK repository. Use when asked to create triage reports, identify high-priority issues, analyze feature area health, find issues needing attention, or generate status dashboards. Triggers on requests involving issue triage, area status, priority analysis, bug tracking reports, or engineering team focus areas.
Link workspace packages in monorepos (npm, yarn, pnpm, bun). USE WHEN: (1) you just created or generated new packages and need to wire up their dependencies, (2) user imports from a sibling package and needs to add it as a dependency, (3) you get resolution errors for workspace packages (@org/*) like "cannot find module", "failed to resolve import", "TS2307", or "cannot resolve". DO NOT patch around with tsconfig paths or manual package.json edits - use the package manager''s workspace commands to fix actual linking.
Generate code using nx generators. INVOKE IMMEDIATELY when user mentions scaffolding, setup, structure, creating apps/libs, or setting up project structure. Trigger words - scaffold, setup, create a ... app, create a ... lib, project structure, generate, add a new project. ALWAYS use this BEFORE calling nx_docs or exploring - this skill handles discovery internally.
Explore and understand Nx workspaces. USE WHEN answering questions about the workspace, projects, or tasks. ALSO USE WHEN an nx command fails or you need to check available targets/configuration before running a task. EXAMPLES: 'What projects are in this workspace?', 'How is project X configured?', 'What depends on library Y?', 'What targets can I run?', 'Cannot find configuration for task', 'debug nx task failure'.
Import, merge, or combine repositories into an Nx workspace using nx import. USE WHEN the user asks to adopt Nx across repos, move projects into a monorepo, or bring code/history from another repository.
Find and add Nx plugins. USE WHEN user wants to discover available plugins, install a new plugin, or add support for a specific framework or technology to the workspace.
Generate multiple radically different interface designs for a module using parallel sub-agents. Use when user wants to design an API, explore interface options, compare module shapes, or mentions "design it twice".
Interactive system flow tracing across CODE, API, AUTH, DATA, NETWORK layers with SQLite persistence and Mermaid export. Use for security audits, compliance documentation, flow tracing, feature ideation, brainstorming, debugging, architecture reviews, or incident post-mortems. Triggers on audit, trace flow, document flow, security review, debug flow, brainstorm, architecture review, post-mortem, incident review.
Use when adding docstrings, creating API documentation, or building documentation sites. Invoke for OpenAPI/Swagger specs, JSDoc, doc portals, tutorials, user guides.
Scan code for security issues: dependency vulnerabilities (npm/pip audit), secret leaks (regex and entropy analysis), and OWASP anti-patterns like SQL injection, XSS, or command injection. Use when the user mentions security scans, vulnerability detection, secret leaks, API keys, OWASP, npm audit, pip-audit, hardcoded passwords, or code security checks.
Analyze codebases and automatically generate architecture diagrams, flowcharts, and org charts. Uses AST parsing to map import dependencies for Python, JS/TS, Go, and Java, outputting Mermaid or SVG files. Triggered when users ask to visualize code architecture, understand dependencies, draw a flowchart, or create a module diagram from source code.
React 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.
Explore a codebase to find opportunities for architectural improvement, focusing on making the codebase more testable by deepening shallow modules. Use when user wants to improve architecture, find refactoring opportunities, consolidate tightly-coupled modules, or make a codebase more AI-navigable.
Interview the user relentlessly about a plan or design until reaching shared understanding, resolving each branch of the decision tree. Use when user wants to stress-test a plan, get grilled on their design, or mentions "grill me".
This skill should be used when setting up, auditing, or enforcing internationalization/localization in UI codebases (React/TS, i18next or similar, JSON locales), including installing/configuring the i18n framework, replacing hard-coded strings, ensuring en-US/zh-CN coverage, mapping error codes to localized messages, and validating key parity, pluralization, and formatting.
Battle-tested Playwright patterns for E2E, API, component, visual, accessibility, and security testing. Covers locators, assertions, fixtures, network mocking, auth flows, debugging, and framework recipes for React, Next.js, Vue, and Angular. TypeScript and JavaScript.