/**
 * Input validation utilities for agent-safety (agentic CLI hardening).
 *
 * Defends against: path traversal, control character injection,
 * and overly long inputs that agents may hallucinate.
 */
/**
 * Reject strings containing control characters (below ASCII 0x20,
 * excluding tab, newline, CR which are sometimes intentional).
 */
export declare function rejectControlChars(value: string, fieldName?: string): string;
/**
 * Validate that a file path does not escape the sandbox directory.
 * Returns the resolved absolute path.
 */
export declare function validateSafePath(inputPath: string, sandbox?: string): string;
/**
 * Validate output path — must not traverse outside cwd unless absolute.
 * Allows absolute paths (user-specified like /tmp/output.mp4).
 */
export declare function validateOutputPath(outputPath: string): string;
/**
 * Validate a user-provided string (prompt text, etc.) for sanity.
 * Rejects control chars and caps length to prevent context abuse.
 */
export declare function validateTextInput(value: string, fieldName?: string, maxLength?: number): string;
