export declare function isValidConversationId(id: string): boolean;
export type ChatHistoryMessage = {
    role: 'user' | 'assistant';
    content: string;
    timestamp: string;
};
export type ChatConversation = {
    id: string;
    title: string;
    messages: ChatHistoryMessage[];
    createdAt: string;
    updatedAt: string;
    messageCount: number;
};
export type ChatConversationMeta = {
    id: string;
    title: string;
    createdAt: string;
    updatedAt: string;
    messageCount: number;
};
/**
 * Lists all conversations in the workspace, returning metadata only (no messages).
 * Sorted by updatedAt descending (most recent first).
 */
export declare function listConversations(workspace: string): ChatConversationMeta[];
/**
 * Loads a full conversation by id, including messages.
 * Returns null if not found.
 */
export declare function loadConversation(workspace: string, id: string): ChatConversation | null;
/**
 * Saves or updates a conversation. Enforces message limit per conversation
 * and conversation count limit per workspace.
 */
export declare function saveConversation(workspace: string, id: string, title: string, messages: ChatHistoryMessage[]): ChatConversation;
/**
 * Deletes a conversation by id.
 * Returns true if the conversation was found and deleted.
 */
export declare function deleteConversation(workspace: string, id: string): boolean;
