import type { z } from "zod";
/** Agent-readable lines for Zod validation issues (union branches flattened). */
export declare function formatIssues(issues: z.core.$ZodIssue[]): string[];
/**
 * `guidance` explains the union's cross-field rule. With `triggers`, it is
 * prepended only when the input sets one of those keys, so an unrelated
 * failure (a typo, a missing field) is not blamed on that rule.
 */
export declare function createUnionValidationError(guidance: string, triggers?: readonly string[]): z.core.$ZodErrorMap;
/**
 * For an implicit union of strict branches: when the closest branch rejects a
 * key that a sibling branch accepts, name the sibling's missing required
 * fields (parity: native `contracts/validate/union.rs` sibling-branch hint).
 * Derived from the per-branch issues, so no branch shapes are needed.
 */
export declare function siblingFieldHints(branches: z.core.$ZodIssue[][], input: unknown): string[];
/**
 * Error map for implicit unions without cross-field guidance. Leaves the
 * default message (and CLI branch flattening) alone unless a sibling hint
 * applies.
 */
export declare function createSiblingUnionError(): z.core.$ZodErrorMap;
type BranchShape = Readonly<Record<string, z.ZodType>>;
/**
 * Unknown-key error for exclusive strict branches: when a sibling branch owns
 * the key, name the fields that branch needs (parity: native
 * `contracts/validate/union.rs` sibling-branch hint).
 */
export declare function createSiblingFieldError(branches: readonly BranchShape[]): z.core.$ZodErrorMap;
export {};