/**
 * Optional per-surface DATA schema for the A2UI engine — the data-model side of
 * the registry's prop typing (findings §4.3). A schema declares the shape of the
 * fields a surface's data model may hold (JSON Pointer → type + optional
 * enum/format/description). It does two things:
 * - documents the declared fields in the system prompt (`a2uiDataSchemaSection`),
 *   so the agent knows which paths exist and what they hold;
 * - validates `updateDataModel` writes against those declarations
 *   (`validateSchemaWrite`), turning a type mismatch on a declared pointer into a
 *   `SCHEMA_TYPE_MISMATCH` error and a write to an undeclared top-level branch
 *   into a `SCHEMA_UNDECLARED_PATH` warning — both relayed through the same
 *   `onValidationError` feedback loop the agent already consumes.
 *
 * Pure TS, no Svelte. Deliberately MINIMAL (v1): exact-pointer type/enum checks
 * and a top-level "did you mean to write here?" warning. Deferred: required
 * fields, nested object schemas, cross-field constraints, and transporting the
 * schema inside the envelope.
 */
import { type A2uiValidationIssue } from './a2ui.types.js';
/** The JSON primitive/shape a declared field holds. */
export type A2uiSchemaType = 'string' | 'number' | 'integer' | 'boolean' | 'array' | 'object';
/** One declared field: its type plus optional enum/format/description for the prompt. */
export interface A2uiSchemaField {
    type: A2uiSchemaType;
    /** Agent-facing description; emitted into the prompt verbatim. */
    description?: string;
    /** Allowed literal values (documented + enforced for string/number fields). */
    enum?: readonly (string | number)[];
    /** A format hint (e.g. `date`, `time`, `email`) — documented, not enforced in v1. */
    format?: string;
}
/** Surface data schema: absolute JSON Pointer → field declaration. */
export type A2uiDataSchema = Readonly<Record<string, A2uiSchemaField>>;
/**
 * Validate one `updateDataModel` write against the schema. `pointer` is the
 * write target (`''`/`'/'`/`undefined` = whole model); `value` is the written
 * value (`undefined` for a delete — never flagged). Returns any schema issues.
 */
export declare function validateSchemaWrite(schema: A2uiDataSchema, pointer: string | undefined, value: unknown, surfaceId?: string): A2uiValidationIssue[];
/**
 * Render the schema as a prompt section listing every declared field, its type
 * and any enum/format/description. Appended by the app after `a2uiSystemPrompt`
 * (like the transport section), NOT baked into the generator.
 */
export declare function a2uiDataSchemaSection(schema: A2uiDataSchema): string;