diff --git a/packages/extension-form/src/internal/FormField.ts b/packages/extension-form/src/internal/FormField.ts
index f266eaf..759b563 100644
--- a/packages/extension-form/src/internal/FormField.ts
+++ b/packages/extension-form/src/internal/FormField.ts
@@ -10,7 +10,6 @@ export interface LiteralFormField<
     S extends Schema.Literal<Literals>,
     Literals extends Array.NonEmptyReadonlyArray<SchemaAST.LiteralValue>,
 > extends FormField<S> {
-    readonly _tag: "LiteralFormField"
     readonly value: S["Type"]
 }
 
@@ -18,7 +17,6 @@ export interface UnionFormField<
     S extends Schema.Union<Members>,
     Members extends ReadonlyArray<Schema.Schema.All>,
 > extends FormField<S> {
-    readonly _tag: "UnionFormField"
     readonly member: Formify.Formify<Members[number]>
 }
 
@@ -27,7 +25,6 @@ export interface TupleFormField<
     Elements extends Schema.TupleType.Elements,
     Rest extends Schema.TupleType.Rest,
 > extends FormField<S> {
-    readonly _tag: "TupleFormField"
     readonly elements: [...{ readonly [K in keyof Elements]: Formify.Formify<Elements[K]> }]
 }
 
@@ -35,7 +32,6 @@ export interface ArrayFormField<
     S extends Schema.Array$<Value>,
     Value extends Schema.Schema.Any,
 > extends FormField<S> {
-    readonly _tag: "ArrayFormField"
     readonly elements: readonly Formify.Formify<Value>[]
 }
 
@@ -43,12 +39,10 @@ export interface StructFormField<
     S extends Schema.Struct<Fields>,
     Fields extends Schema.Struct.Fields,
 > extends FormField<S> {
-    readonly _tag: "StructFormField"
     readonly fields: { readonly [K in keyof Fields]: Formify.Formify<Fields[K]> }
 }
 
 export interface GenericFormField<S extends Schema.Schema.Any> extends FormField<S> {
-    readonly _tag: "GenericFormField"
     readonly value: S["Type"]
 }
 
@@ -63,7 +57,6 @@ export interface PropertySignatureFormField<
     HasDefault extends boolean = false,
     R = never,
 > {
-    readonly _tag: "PropertySignatureFormField"
     readonly propertySignature: S
     readonly value: Type
 }