/**
 * Validates a DID according to AT Protocol specifications
 * @param did - The DID to validate
 * @throws {AtProtocolValidationError} If the DID is invalid
 */
export declare function validateDid(did: string): void;
/**
 * Validates a URI according to AT Protocol specifications
 * @param uri - The URI to validate
 * @throws {AtProtocolValidationError} If the URI is invalid
 */
export declare function validateUri(uri: string): void;
/**
 * @deprecated Use validateUri instead which supports both did: and at:// URIs
 */
export declare function validateAtUri(uri: string): void;
/**
 * Validates if a string is a valid CID (Content Identifier)
 * This validation checks the format for CIDv0 and CIDv1 (base32 and base58)
 * @param cidStr The CID string to validate
 * @throws {AtProtocolValidationError} If the CID is invalid
 */
export declare function validateCid(cidStr: string): void;
/**
 * Validates a label value according to AT Protocol specifications.
 * The value must:
 * - Be a string with max 128 bytes
 * - Not contain whitespace
 * - Use only ASCII characters
 * - Not contain special punctuation except for '!' prefix
 * @param val - The label value to validate
 * @throws {AtProtocolValidationError} If the value is invalid
 */
export declare function validateVal(val: string): void;
/**
 * Validates a timestamp string according to AT Protocol specifications.
 * The timestamp must be in ISO 8601 format and represent a valid date.
 *
 * @param timestamp - The timestamp string to validate
 * @param fieldName - The name of the field being validated ('cts' or 'exp')
 * @param allowExpired - Whether to allow expired timestamps
 * @throws {AtProtocolValidationError} If the timestamp is invalid
 */
export declare function validateTimestamp(timestamp: string, fieldName: 'cts' | 'exp', allowExpired?: boolean): void;
/**
 * Validates a creation timestamp (cts) according to AT Protocol specifications.
 * @param cts - The creation timestamp to validate
 * @throws {AtProtocolValidationError} If the timestamp is invalid
 */
export declare function validateCts(cts: string): void;
/**
 * Validates an expiration timestamp (exp) according to AT Protocol specifications.
 * @param exp - The expiration timestamp to validate
 * @param allowExpired - Whether to allow expired timestamps
 * @throws {AtProtocolValidationError} If the timestamp is invalid
 */
export declare function validateExp(exp: string, allowExpired?: boolean): void;