Gemini RAG MCP Server

/** * Base tool abstract class */ import type { ZodSchema } from "zod"; import type { ToolContext, ToolDefinition, ToolResponse } from "../base-tool.js"; import { createToolResponse, convertToJsonSchema } from "../base-tool.js"; import { logger } from "../../utils/logger.js"; /** * Abstract base class for all MCP tools * Implements Template Method pattern for tool definition */ export abstract class BaseTool<TArgs = Record<string, unknown>> { /** * Tool name (must be unique across all tools) */ abstract readonly name: string; /** * Tool description for MCP clients */ abstract readonly description: string; constructor(protected readonly context: ToolContext) {} /** * Get Zod schema for input validation * Override this method to define tool-specific input schema */ abstract getInputSchema(): ZodSchema; /** * Execute the tool logic * Override this method to implement tool-specific behavior * @param args - Validated input arguments * @returns Tool execution result (can be sync or async) */ abstract execute(args: TArgs): unknown; /** * Default handler that wraps execute() with response creation * Handles errors and returns error response with isError flag * * Error handling strategy: * - Catches all errors thrown by execute() * - Logs error details for debugging (without sensitive information) * - Returns error.message to AI client for appropriate action * - Sets isError: true to indicate error state * * Can be overridden if custom response handling is needed */ async handler(args: TArgs): Promise<ToolResponse> { try { const result = await this.execute(args); return createToolResponse(result); } catch (error) { // Log error for debugging (error object does not contain sensitive args) logger.error(`[${this.name}] Error`, { error }); // Return error message to AI client return { content: [ { type: "text", text: error instanceof Error ? error.message : String(error), }, ], isError: true, }; } } /** * Convert this tool instance to a ToolDefinition * Used by ToolRegistry for MCP server registration */ toDefinition(): ToolDefinition<TArgs> { return { name: this.name, description: this.description, inputSchema: convertToJsonSchema(this.getInputSchema()), handler: this.handler.bind(this), }; } }