# Types reference > Every public type Attaform exports, grouped by purpose. Inference handles the common cases; these are for advanced wiring (custom adapters, deeply nested generic helpers, type-safe consumer libraries). This page is reference material, alphabetical-ish by purpose. Most consumers never reach for these directly; the [Inference-first DX](/docs/schemas/contract) doctrine means `useForm` + a schema gives you autocomplete on every reactive surface without naming the types. ## Form configuration | Type | Source | Purpose | | ----------------------------------- | ----------------------- | ----------------------------------------------------------------------------------------- | | `UseFormConfiguration
` | runtime/types/types-api | The options bag passed to `useForm`. | | `UseFormReturnType` | runtime/types/types-api | The whole reactive return: values, fields, errors, meta, methods. | | `AttaformPluginOptions` | runtime/core/plugin | Options for `createAttaform({ defaults, devtools })`. | | `AttaformDefaults` | runtime/types/types-api | The fields settable via `createAttaform({ defaults })`. | | `HistoryConfig` | runtime/types/types-api | `useForm({ history })` shape. | | `OnInvalidSubmitPolicy` | runtime/types/types-api | `'none'` \| `'focus-first-error'` \| `'scroll-to-first-error'` \| `'both'`. | | `ValidateOn` / `ValidateOnConfig` | runtime/types/types-api | `validateOn` field and its discriminated config. | | `DisplayState` / `GetDisplayState` | runtime/types/types-api | The display-state verdict (`idle` \| `pending` \| `error` \| `success`) and its resolver. | ## Reactive surfaces | Type | Source | Purpose | | ------------------------------- | ----------------------- | --------------------------------------------------------- | | `FieldState` | runtime/types/types-api | The 31-property per-leaf reactive bundle. | | `FieldStateMap` / `Entry` | runtime/types/types-api | The proxy shape exposing `form.fields`. | | `FormMeta` | runtime/types/types-api | Form-level aggregates over every field's state. | | `FormErrorsSurface` | runtime/types/types-api | The proxy shape exposing `form.errors`. | | `FormErrorRecord` | runtime/types/types-api | The per-path error array shape. | | `ErrorsProxyShape` | runtime/types/types-api | Type-level view of the errors proxy for advanced helpers. | | `WriteMeta` | runtime/types/types-api | Metadata attached to a mutation (source, batch flags). | ## Validation | Type | Source | Purpose | | ----------------------------------------------------- | ----------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `ValidationError` | runtime/types/types-api | The error shape (`{ path, message, code, formKey, data? }`). | | `ErrorInput` | runtime/types/types-api | What `form.setErrors` accepts: an `Error` or `{ message?, path?, code?, data? }`. `formKey` is also accepted but ignored (the form stamps its own), so `ValidationError` is a subtype. | | `Json` | runtime/types/types-api | JSON-serialisable value; the type of the optional `data` payload. | | `ValidationResponse` | runtime/types/types-api | Discriminated success-or-failure validation result with parsed data. | | `ValidationResponseWithoutValue` | runtime/types/types-api | Same shape minus the `data` payload (used by `validateAsync`). | | `ReactiveValidationStatus` | runtime/types/types-api | Discriminated pending-vs-settled reactive validation status. | | `PendingValidationStatus` / `SettledValidationStatus` | runtime/types/types-api | The two branches of `ReactiveValidationStatus`. | | `HandleSubmit` / `OnSubmit` / `OnError` | runtime/types/types-api | The `handleSubmit` callback signatures. | | `SubmitHandler` | runtime/types/types-api | Generic handler type for typed user submit functions. | ## Schema contract | Type | Source | Purpose | | -------------------------------- | ----------------------- | ---------------------------------------------------------------- | | `AbstractSchema` | runtime/types/types-api | The 12-method + 2-optional contract custom adapters implement. | | `DefaultValuesResponse` | runtime/types/types-api | What `getDefaultValues` returns. | | `SlimPrimitiveKind` | runtime/types/types-api | `'string'` \| `'number'` \| … (typeof-style kinds). | | `SlimRuntimeOf` | runtime/types/types-api | Type-level helper to compute the slim primitive set for a type. | | `FieldMetaPayload` | runtime/types/types-api | Schema-attached metadata: label, description, placeholder, meta. | ## Path types | Type | Source | Purpose | | ------------------------------ | ------------------------ | -------------------------------------------------------- | | `FlatPath` | runtime/types/types-core | Every reachable dotted path through the form. | | `PartialFlatPath` | runtime/types/types-core | Same but allowing partial-prefix paths. | | `ArrayPath` | runtime/types/types-core | Every reachable path whose value is an array. | | `JoinSegments` | runtime/types/types-core | Type-level join of a segment tuple into a dotted string. | | `Path` / `PathKey` / `Segment` | runtime/core/paths | Canonicalized runtime path representation. | ## Shape helpers | Type | Source | Purpose | | ----------------------------------------------------------------- | ------------------------ | ---------------------------------------------------------------- | | `GenericForm` | runtime/types/types-core | The most-permissive form shape; used in generics that constrain. | | `DeepPartial` | runtime/types/types-core | Every leaf made optional, recursively. | | `DefaultValuesInput` / `DefaultValuesShape` | runtime/types/types-core | The `defaultValues` argument shape vs. the resolved tree. | | `WriteShape` | runtime/types/types-core | The shape `setValue` accepts (`z.input`-equivalent). | | `NestedReadType` / `NestedType` | runtime/types/types-core | Walk a type to the value at a path. | | `LiftedValueShape` | runtime/types/types-core | Helper for variant-memory and discriminated-union plumbing. | | `ArrayItem` | runtime/types/types-core | Element type of an array. | | `IsTuple` / `IsUnion` / `KeyofUnion` / `ValueOfUnion` | runtime/types/types-core | Type-level predicates and unions over generic values. | | `Primitive` | runtime/types/types-core | The base primitive set. | ## Binding | Type | Source | Purpose | | ------------------------------------------------- | -------------------------------- | ---------------------------------------------------------------- | | `RegisterDirective` | runtime/types/types-api | The `v-register` directive type. | | `RegisterValue` / `RegisterOptions` | runtime/types/types-api | The value the directive accepts; the per-register options shape. | | `RegisterFlatPath` | runtime/types/types-api | Paths bindable through `register`. | | `RegisterTextModifier` / `RegisterSelectModifier` | runtime/types/types-api | The `.lazy` / `.trim` / `.number` modifier types. | | `RegisterTransform` | runtime/types/types-api | Custom DOM ↔ value transform shape. | | `CustomDirectiveRegisterAssignerFn` | runtime/types/types-api | The `assignKey` custom-assigner signature. | | `UseRegisterReturn` | runtime/composables/use-register | What `useRegister()` returns. | ## Set / mutate | Type | Source | Purpose | | ------------------------ | ----------------------- | ------------------------------------------------------------ | | `SetValuePayload` | runtime/types/types-api | Whole-form merge payload shape. | | `SetValueCallback` | runtime/types/types-api | The `(prev) => next` callback signature. | | `MetaTrackerValue` | runtime/types/types-api | Internal "I'm mutating" flag exposed for advanced consumers. | | `Unset` | runtime/core/unset | The `unset` sentinel's brand type. | ## SSR payload | Type | Source | Purpose | | ------------------------- | ---------------------- | ------------------------------- | | `SerializedAttaformState` | runtime/core/serialize | The SSR payload shape. | | `SerializedFormData` | runtime/core/registry | Single form's serialized state. | ## Wizard | Type | Source | Purpose | | -------------------------------------------- | -------------------------- | ------------------------------------------------------- | | `UseWizardReturnType` | runtime/types/types-wizard | The whole wizard return: current, statuses, navigation. | | `WizardOptions` | runtime/types/types-wizard | The options bag. | | `AnyForm` / `FormKeyOf` / `KeysOf` | runtime/types/types-wizard | Helpers for typing forms passed to `useWizard`. | | `WizardNavOptions` | runtime/types/types-wizard | Options forwarded to `next` / `back` / `goTo`. | ## DevTools | Type | Source | Purpose | | ------------------------ | ---------------------------- | ----------------------------------------------------- | | `AttaformDevtoolsBridge` | runtime/core/devtools-shared | The window-bridge contract the Nuxt overlay consumes. | ## Coercion | Type | Source | Purpose | | ------------------------------------------------------- | ----------------------- | ---------------------------------- | | `CoercionEntry` / `CoercionRegistry` / `CoercionResult` | runtime/types/types-api | The schema-driven coercion shapes. | ## Internal-only (not for direct consumption) These types ride on internal helpers and are exported for advanced custom-adapter authors. The [Inference-first DX](/docs/schemas/contract) doctrine means everyday consumers never need them: - `StorageLeaf` / `StorageShape`: the slim-write-shape internal representations the runtime walks. - `PartialFlatPath`: used by the path-prefix matchers inside the runtime. - `LiftedValueShape`: variant-memory plumbing. Treat them as appendix items: stable enough to reference, but the public-facing surfaces (`UseFormReturnType`, `FieldState`, `ValidationError`) are what consumer code should depend on. ## Where to next - [The schema contract](/docs/schemas/contract): the high-level model these types implement. - [`AbstractSchema`](/docs/schemas/abstract-schema): when you need the contract for a non-Zod schema library. - [Entry-point reference](/docs/reference/entry-points): which subpath each type ships from.