/**
 * Tools that mutate GA4 state. These are hidden from the tool list and
 * refused at call time unless GA4_MCP_WRITE=true.
 *
 * ga4_send_feedback / ga4_suggest_improvement only append to local log files
 * — they never touch GA4 remote state — so they stay ungated.
 *
 * Adding a new tool? Put it in this set if it creates, updates, deletes, or
 * publishes anything in GA4. The shape test in writeGate.test.ts enforces
 * this by name pattern.
 */
export declare const WRITE_TOOLS: ReadonlySet<string>;
export declare function isWriteTool(name: string): boolean;
export declare function isWriteEnabled(env?: NodeJS.ProcessEnv): boolean;
export declare function filterTools<T extends {
    name: string;
}>(allTools: readonly T[], env?: NodeJS.ProcessEnv): T[];
export declare const WRITE_DISABLED_MESSAGE: string;
/**
 * Assert that a tool call is allowed under the current write-mode setting.
 * Throws a clear Error if the tool mutates state and writes are disabled.
 */
export declare function assertWriteAllowed(toolName: string, env?: NodeJS.ProcessEnv): void;