DeFi Trading Agent MCP Server

Instructions

Implementation Reference

• src/toolService.js:22-38 (handler)

  Primary MCP tool handler for 'get_swap_price': validates input parameters and delegates to AgService.getSwapPrice

  async getSwapPrice(params) {
    // Validate required parameters
    const { chainId, buyToken, sellToken, sellAmount } = params;
  
    if (!chainId || !buyToken || !sellToken || !sellAmount) {
      throw new Error(
        "Missing required parameters: chainId, buyToken, sellToken, sellAmount"
      );
    }
  
    const result = await this.agg.getSwapPrice(params);
  
    return {
      message: "Swap price retrieved successfully",
      data: result,
    };
  }

• src/services/agService.js:9-27 (handler)

  Core implementation of getSwapPrice: makes HTTP GET request to aggregator API endpoint /api/swap/price with query parameters

  async getSwapPrice(params) {
    try {
      const queryParams = new URLSearchParams(params);
      const response = await fetch(`${this.baseUrl}/api/swap/price?${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 || 'API request failed');
      }
      
      return data.data;
    } catch (error) {
      throw new Error(`Failed to get swap price: ${error.message}`);
    }

• src/index.js:984-985 (registration)

  MCP server registration: routes 'get_swap_price' tool calls to ToolService.getSwapPrice method

  case TOOL_NAMES.GET_SWAP_PRICE:
    result = await toolService.getSwapPrice(args);

• src/index.js:90-119 (schema)

  Tool specification including name, description, and input schema validation for 'get_swap_price' in MCP ListTools response

    name: TOOL_NAMES.GET_SWAP_PRICE,
    description:
      "Get indicative price for a token swap using Aggregator Protocol",
    inputSchema: {
      type: "object",
      properties: {
        chainId: {
          type: "integer",
          description: "Blockchain ID (e.g., 1 for Ethereum)",
        },
        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 (optional)",
        },
      },
      required: ["chainId", "buyToken", "sellToken", "sellAmount"],
    },
  },

• src/constants.js:4-4 (registration)

  Constant definition mapping TOOL_NAMES.GET_SWAP_PRICE to the tool name string 'get_swap_price' used throughout the codebase

  GET_SWAP_PRICE: "get_swap_price",