/**
 * Base Model Class
 *
 * Abstract base class for all data models.
 * Models are pure data containers - they never make API calls.
 */
/**
 * Abstract base class for all data models.
 *
 * - **Immutable**: Data is frozen on construction
 * - **Pure data**: No API calls, just typed accessors
 * - **Serializable**: `toJSON()` returns the raw data
 *
 * @typeParam TData - The raw data type this model wraps
 *
 * @example
 * ```typescript
 * class Client extends BaseModel<BaseClientData> {
 *   get id(): string { return this._data.id; }
 *   get name(): string { return this._data.name; }
 * }
 * ```
 */
export declare abstract class BaseModel<TData extends object> {
    /**
     * The underlying raw data.
     * Frozen to ensure immutability.
     */
    protected readonly _data: TData;
    constructor(data: TData);
    /**
     * Returns the raw data object.
     * Useful for serialization and debugging.
     */
    toJSON(): TData;
    /**
     * Returns a string representation of the model.
     * Override in subclasses for better output.
     */
    toString(): string;
}