react-forms

Implements TanStack Form v1 in React: core hooks (`useForm()`, `useField()`, `form.Field`, `form.Subscribe`), native Standard Schema validation (Zod ~12KB, Yup ~40KB, Valibot ~6KB, ArkType, Effect Schema — no adapter package), debounced async validation, and React 19 Server Actions integration via `useActionState`.

Also covers array/nested fields with dot notation, listeners for side effects (onMount/onChange/onBlur with debouncing), linked/cross-field validation, reactivity via useStore selectors, the Reset API, SSR/hydration (TanStack Start), devtools, and React Native patterns. This is the React skill for TanStack Form — for the Next.js Server Actions-specific variant see nextjs-tanstack-form, and for SOLID file-organization rules see solid-react.

TanStack Form v1 Core Features

Agent Workflow (MANDATORY)

Before ANY implementation, spawn 3 agents in parallel, one Agent call each with a name:

1. fuse-ai-pilot:explore-codebase - Analyze existing form components and validation patterns
2. fuse-ai-pilot:research-expert - Verify latest TanStack Form v1 docs via Context7/Exa
3. mcp__context7__query-docs - Check Zod validation and React 19 Server Actions patterns

After implementation, run fuse-ai-pilot:sniper for validation.

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MANDATORY: SOLID Principles

ALWAYS apply SOLID principles from solid-react skill.

→ See ../solid-react/SKILL.md for complete rules

Key Rules:

• Source files stay within FUSE_SOLID_MAX_LINES and split by responsibility when cohesion drops
• Interfaces in modules/[feature]/src/interfaces/
• JSDoc mandatory on all exports
• No business logic in components

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Core Hooks

Hook	Purpose	Guide
useForm()	Initialize form with validation	references/tanstack-form-basics.md
useField()	Subscribe to individual field	references/tanstack-form-basics.md
form.Field	Render prop component for fields	references/tanstack-form-basics.md
form.Subscribe	Watch form state changes	references/tanstack-form-basics.md

→ See references/tanstack-form-basics.md for detailed usage

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Validation Adapters

TanStack Form v1 (@tanstack/react-form 1.33.x) supports Standard Schema natively — pass the schema itself to validators (onChange: userSchema). No adapter: validatorAdapter and @tanstack/zod-form-adapter (last release 0.42.1, pre-v1, Zod 3 only) are removed/obsolete.

Library	Usage	Min version	Bundle Size
Zod	validators: { onChange: schema }	3.24.0	~12KB
Yup	validators: { onChange: schema }	1.7.0	~40KB
Valibot	validators: { onChange: schema }	1.0.0	~6KB

→ See references/zod-validation.md for Zod patterns → See references/yup-valibot.md for alternatives

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Key Features

Async Validation

Server-side checks with debouncing and loading states. → See references/async-validation.md

Server Actions (React 19)

Integration with useActionState and progressive enhancement. → See references/server-actions.md

Arrays & Nested Fields

Dynamic field arrays and dot notation for nested objects. → See references/arrays-nested.md

TypeScript Integration

Full type inference from Zod schemas and defaultValues. → See references/typescript.md

shadcn/ui Integration

Field wrapper components with shadcn styling. → See references/shadcn-integration.md

Listeners (Side Effects)

onMount, onChange, onBlur, onSubmit with debouncing. → See references/listeners.md

Linked Fields

Cross-field validation and dependent dropdowns. → See references/linked-fields.md

Reactivity & Performance

useStore selectors and granular subscriptions. → See references/reactivity.md

Reset API

Form and field reset with custom values. → See references/reset-api.md

SSR & Hydration

TanStack Start integration and server state merge. → See references/ssr-hydration.md

Devtools

Debug form state with @tanstack/react-form-devtools. → See references/devtools.md

React Native

Mobile-specific patterns with TextInput. → See references/react-native.md

Standard Schema

ArkType and Effect Schema support. → See references/standard-schema.md

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Templates

Template	Use Case
templates/basic-form.md	Login/signup with Zod
templates/multi-step-form.md	Wizard with step validation
templates/dynamic-fields.md	Add/remove field arrays
templates/file-upload-form.md	File input with preview
templates/server-action-form.md	React 19 Server Actions
templates/optimistic-form.md	useOptimistic integration
templates/nested-form.md	Dot notation nested fields
templates/search-form.md	Debounced search
templates/conditional-fields.md	Show/hide based on values
templates/form-composition.md	Reusable field components
templates/listeners-form.md	Side effects & auto-save
templates/linked-fields-form.md	Cross-field validation
templates/reactivity-form.md	Performance optimization
templates/reset-form.md	Form/field reset patterns
templates/ssr-form.md	SSR & hydration
templates/devtools-form.md	Devtools integration
templates/react-native-form.md	React Native forms

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Best Practices

1. Validation: Use Zod/Yup/Valibot, NOT custom regex
2. Async: Debounce server validation (300-500ms)
3. Errors: Display field.state.meta.errors
4. Nested: Use dot notation (address.street)
5. Arrays: Use mode="array" with pushValue/removeValue
6. TypeScript: Infer types with z.infer<typeof schema>

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Forbidden (Anti-Patterns)

• ❌ useState for form state → use useForm()
• ❌ Regex validation → use Zod/Yup/Valibot
• ❌ No debounce on async → use onChangeAsyncDebounceMs
• ❌ Validation in components → move to schema
• ❌ Direct onChange → use field.handleChange
• ❌ No TypeScript types → use z.infer<typeof schema>