Use this skill when extending the Sitefinity admin backend UI with Angular AdminApp extensions - building custom field editors that override backend content-edit fields, registering NgModules against the host extension store, matching fields by fieldName/fieldType/typeName, calling authenticated backend OData with HTTP_PREFIX, wiring the dev server, and deploying the extensions bundle so Sitefinity discovers it.
Use this skill when starting ANY Sitefinity CMS task, when you are unsure which Sitefinity skill applies, when you need general Sitefinity MVC development guidance, when choosing a data-access approach for Sitefinity content, or when you need to verify which Sitefinity and .NET versions a project targets before writing code - it is the read-this-first foundation that establishes context, states the ground rules, and routes you to the right deep skill.
Comprehensive reference for every attribute available in Sitefinity's autogenerated widget property editors (MVC and ASP.NET Core renderer) - field types, display/validation attributes, sections, conditional visibility, content selectors, LinkModel, TableView, choices, and KnownFieldTypes string values. Use when building or configuring widget designer fields.
Use this skill when querying Sitefinity content over REST/OData, hitting the /api/default endpoints, reading the sfhelp service document, exposing content types or Module Builder dynamic module data through web services, answering $filter/$expand/$select/paging questions, or deciding between the built-in default OData web service and writing a custom API.
Quick-reference map of how Sitefinity stores page widgets and their properties (sf_object_data + sf_control_properties), the two-level property hierarchy, SiblingId render ordering, and ready-to-use SQL for reading widget content. Use for fast lookups; the sitefinity-database-structure skill is the full reference.
Use this skill when building JSON/REST APIs inside a Sitefinity MVC site, writing or registering ServiceStack services, wiring /RestApi routes, securing API endpoints with Sitefinity roles and identity, or diagnosing DateTime serialization problems where JavaScript shows "Invalid Date" from a Sitefinity endpoint.
Reference list of built-in Sitefinity toolbox icon CSS classes for the CssClass property on ControllerToolboxItem, plus the page-editor CSS that badges MVC widgets during WebForms-to-MVC migrations. Use when adding a new MVC widget and picking its toolbox icon.
Complete setup guide for adding a Vue 3 + Vite 8 (Rolldown) + Tailwind CSS v4 + shadcn-vue frontend to a classic Sitefinity MVC site - data-island widgets, code splitting, design-mode mounting, search indexing, Sentry error bridge, HMR dev server, and IIS considerations. Use when building or troubleshooting this stack on Sitefinity.