Guides creation and modification of ASP.NET Core Web API endpoints with correct HTTP semantics, OpenAPI metadata, and error handling. USE FOR: adding new API endpoints (controllers or minimal APIs), wiring up OpenAPI/Swagger, creating .http test files, setting up global error handling middleware.
Install
npx skills add dotnet/skills --skill dotnet-webapinpx skills add dotnet/skills --skill dotnet-webapi -a claude-code -gnpx skills add dotnet/skills --skill dotnet-webapi -a codex -ggemini skills install https://github.com/dotnet/skills.git --path plugins/dotnet-aspnetcore/skills/dotnet-webapigh skill install dotnet/skills dotnet-webapigit clone --depth 1 https://github.com/dotnet/skills /tmp/dotnet__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/dotnet__skills/plugins/dotnet-aspnetcore/skills/dotnet-webapi ~/.claude/skills/dotnet-webapi # Claude Code
cp -R /tmp/dotnet__skills/plugins/dotnet-aspnetcore/skills/dotnet-webapi ~/.agents/skills/dotnet-webapi # Codex, Cursor, Gemini CLI, Copilot, OpenCode