DeFi Trading Agent MCP Server

Instructions

Implementation Reference

• src/toolService.js:433-469 (handler)

  Primary MCP tool handler: validates params, ensures taker address, delegates to AgService.getGaslessQuote, formats MCP response with next steps and gasless info
  async getGaslessQuote(params) { const { chainId, buyToken, sellToken, sellAmount } = params; if (!chainId || !buyToken || !sellToken || !sellAmount) { throw new Error( "Missing required parameters: chainId, buyToken, sellToken, sellAmount" ); } // Add taker address if not provided (required for gasless quotes) const quoteParams = { ...params, taker: params.taker || this.userAddress, }; if (!quoteParams.taker) { throw new Error("Taker address is required for gasless quotes"); } const result = await this.agg.getGaslessQuote(quoteParams); return { message: "Gasless swap quote retrieved successfully", data: result, nextSteps: [ "1. Review the quote details including approval and trade objects", "2. Use submit_gasless_swap tool to execute this gasless swap", "3. Both approval and trade signatures will be handled automatically", ], gaslessInfo: { hasApproval: !!result.approval, hasTrade: !!result.trade, approvalType: result.approval?.type, tradeType: result.trade?.type, }, }; }
• src/index.js:670-705 (schema)

  Input schema and metadata definition for the get_gasless_quote tool in MCP ListTools response
  name: TOOL_NAMES.GET_GASLESS_QUOTE, description: "Get executable quote for a gasless token swap with EIP-712 signature data", inputSchema: { type: "object", properties: { chainId: { type: "integer", description: "Blockchain ID (e.g., 8453 for Base)", }, buyToken: { type: "string", description: "Contract address of token to buy", }, sellToken: { type: "string", description: "Contract address of token to sell", }, sellAmount: { type: "string", description: "Amount of sellToken in base units", }, taker: { type: "string", description: "Address executing the trade (required for gasless quotes, uses USER_ADDRESS from env if not provided)", }, slippageBps: { type: "integer", description: "Maximum acceptable slippage in basis points (optional, min: 30)", }, }, required: ["chainId", "buyToken", "sellToken", "sellAmount"], }, },
• src/index.js:1142-1144 (registration)

  MCP server switch case registration that calls ToolService.getGaslessQuote
  case TOOL_NAMES.GET_GASLESS_QUOTE: result = await toolService.getGaslessQuote(args); break;
• src/services/agService.js:139-158 (helper)

  AgService helper: Makes HTTP request to aggregator's /api/swap/gasless/quote endpoint and handles response/error
  async getGaslessQuote(params) { try { const queryParams = new URLSearchParams(params); const response = await fetch(`${this.baseUrl}/api/swap/gasless/quote?${queryParams}`); if (!response.ok) { throw new Error(`HTTP ${response.status}: ${response.statusText}`); } const data = await response.json(); if (!data.success) { throw new Error(data.error || 'Gasless quote request failed'); } return data.data; } catch (error) { throw new Error(`Failed to get gasless quote: ${error.message}`); } }
• src/constants.js:12-12 (registration)

  Tool name constant definition used for registration and dispatch
  GET_GASLESS_QUOTE: "get_gasless_quote",