import { type ChatState } from "@codingame/monaco-vscode-api/vscode/vs/platform/agentHost/common/state/protocol/channels-chat/state";
import type { ChatAction } from "@codingame/monaco-vscode-api/vscode/vs/platform/agentHost/common/state/protocol/action-origin.generated";
/**
 * Pure reducer for chat state. Handles all {@link ChatAction} variants.
 */
export declare function chatReducer(state: ChatState, action: ChatAction, log?: (msg: string) => void): ChatState;