Formkit

FormKit is an open source form framework for React and Vue, now positioned specifically around code written by AI agents. Its design goal is to remove the boilerplate that makes forms hard for a model to reason about: one compact component API covers every input type, validation rules live on the input itself rather than in a separate schema, and form data structures itself automatically from the component tree at any nesting depth. That structure is the central idea. Groups, repeaters and nested components contribute their own keys to a single predictable data object without prop drilling, event wiring or an ad hoc state store, so generated forms stay editable and consistent as a product evolves. Schema overrides, theming, validation messages and submission handling are built in. The project ships an installable agent skill through a single command so a coding assistant picks up the conventions directly, and the documentation site lets you switch between React and Vue examples. The core library is free and open source. FormKit Pro is the paid add on, providing production ready synthetic inputs including autocomplete, datepicker, repeater and tag list. Pro inputs run without a license on localhost and development domains, so the cost applies only at production. The published figures are $149 for a production license and from $1,250 for Enterprise, both listed as one time payments, with Single Domain and Multi Domain variants and billing options labeled pay as you go, monthly, annual and one time; prices for the individual billing options are not broken out on the page. The same small team in Charlottesville, Virginia also maintains AutoAnimate, Tempo and a drag and drop library.