/**
 * Permission Pre-Filter — risk-based tool approval matrix.
 *
 * Pure functions that determine whether a tool execution should be
 * auto-approved or require explicit approval, based on the tool's
 * risk category and the configured permission level.
 */
import type { PermissionLevel, ToolRiskCategory } from "./types.js";
import type { ToolModule } from "../tools/interface.js";
/**
 * Check whether a tool should be auto-approved or needs approval.
 * Falls back to safe defaults for unknown levels or risk categories.
 */
export declare function checkToolPermission(level: PermissionLevel, risk: ToolRiskCategory): "auto" | "ask";
/**
 * Look up a tool's risk category by name from the tool module registry.
 * Returns "destructive" for unknown tools (safe default).
 */
export declare function getToolRiskCategory(toolName: string, toolModules: ToolModule[]): ToolRiskCategory;
/**
 * Resolve the effective permission level from multiple config sources.
 * Priority: flag > env var > config file > default.
 * Invalid values silently fall through to the next source.
 */
export declare function resolvePermissionLevel(flagLevel?: string, envVar?: string, configLevel?: string): PermissionLevel;