react-hook-form

react-hook-form is a performance optimization guide for building client-side controlled forms with the React Hook Form library. It packages community best practices into 45 rules across 8 categories, prioritized by impact, to steer form development, automated refactoring, and code generation. The skill targets a recurring pain point in React forms: unnecessary re-renders and misconfigured subscriptions that degrade performance as forms grow. It applies when writing new forms, configuring useForm options, subscribing to values with watch, useWatch, or the v7.55+ subscribe() API, integrating controlled UI components, and reviewing forms for performance issues.

The rules are organized by priority prefix. Form Configuration (formcfg-) and Field Subscription (sub-) are marked CRITICAL, covering guidance such as using onSubmit validation mode, providing defaultValues, enabling shouldUnregister for dynamic forms, preferring useWatch over watch for isolated re-renders, and using subscribe() for non-UI side effects like analytics and autosave. HIGH-priority categories cover Controlled Components (ctrl-, e.g. isolating inputs, avoiding double registration with useController) and Validation Patterns (valid-, e.g. defining schemas outside the component for resolver caching, surfacing server errors via setError('root.serverError', ...)). Lower-priority categories address Field Arrays (using field.id as key), State Management, Integration Patterns for MUI and shadcn, and Advanced Patterns like wrapping FormProvider children with React.memo. Each rule has a dedicated reference file under references/{prefix}-{slug}.md with explanations and code examples, and a full compiled guide lives in AGENTS.md.

The skill is aimed at frontend developers already committed to React Hook Form who need reliable, performance-conscious patterns. It explicitly does not cover React 19 Server Actions, useActionState, or server-side form handling (deferring to a react-19 skill), and notes that TanStack Form may fit deeply nested type-safe forms better, while trivial single-input forms may be simpler with uncontrolled form plus FormData. It references companion skills for Zod schema validation and UI/UX form design.