DeFi Trading Agent MCP Server

Instructions

Implementation Reference

• src/toolService.js:749-777 (handler)

  The main handler function that executes the wei to formatted conversion logic using ethers.formatUnits, including input validation and formatted response.

  async convertWeiToFormatted(params) {
    const { amount, decimals } = params;
  
    if (!amount) {
      throw new Error("amount is required");
    }
  
    if (decimals === undefined || decimals === null) {
      throw new Error("decimals is required");
    }
  
    try {
      // Convert the amount to a BigNumber and format it
      const formattedAmount = ethers.formatUnits(amount.toString(), decimals);
  
      return {
        message: "Wei to formatted conversion completed successfully",
        data: {
          originalAmount: amount.toString(),
          decimals: decimals,
          formattedAmount: formattedAmount,
          unit: decimals === 18 ? "ETH" : `${decimals} decimals`,
        },
        summary: `Converted ${amount} wei to ${formattedAmount} (${decimals} decimals)`,
      };
    } catch (error) {
      throw new Error(`Wei to formatted conversion failed: ${error.message}`);
    }
  }

• src/index.js:934-952 (registration)

  MCP tool registration including name, description, and input schema definition.

    name: TOOL_NAMES.CONVERT_WEI_TO_FORMATTED,
    description:
      "Convert wei amounts to human-readable format using ethers.js",
    inputSchema: {
      type: "object",
      properties: {
        amount: {
          type: "string",
          description: "Amount in wei (as string to handle large numbers)",
        },
        decimals: {
          type: "integer",
          description:
            "Number of decimal places for the token (e.g., 18 for ETH, 6 for USDC)",
        },
      },
      required: ["amount", "decimals"],
    },
  },

• src/index.js:937-951 (schema)

  Input schema for the tool defining parameters amount (string) and decimals (integer).

  inputSchema: {
    type: "object",
    properties: {
      amount: {
        type: "string",
        description: "Amount in wei (as string to handle large numbers)",
      },
      decimals: {
        type: "integer",
        description:
          "Number of decimal places for the token (e.g., 18 for ETH, 6 for USDC)",
      },
    },
    required: ["amount", "decimals"],
  },

• src/constants.js:44-44 (helper)

  Constant defining the tool name string for use in registration and dispatch.

  CONVERT_WEI_TO_FORMATTED: "convert_wei_to_formatted",

• src/index.js:1174-1176 (registration)

  Dispatch case in the main tool request handler that routes execution to the toolService handler.

  case TOOL_NAMES.CONVERT_WEI_TO_FORMATTED:
    result = await toolService.convertWeiToFormatted(args);
    break;