DeFi Trading Agent MCP Server

Instructions

Implementation Reference

• src/index.js:181-194 (schema)

  MCP tool schema definition including name, description, and input schema requiring chainId.

  {
    name: TOOL_NAMES.GET_LIQUIDITY_SOURCES,
    description:
      "Get list of liquidity sources available on a specific chain",
    inputSchema: {
      type: "object",
      properties: {
        chainId: {
          type: "integer",
          description: "Blockchain ID to get sources for",
        },
      },
      required: ["chainId"],
    },

• src/index.js:1000-1002 (registration)

  Registration and dispatch in the MCP CallToolRequestHandler switch statement.

  case TOOL_NAMES.GET_LIQUIDITY_SOURCES:
    result = await toolService.getLiquiditySources(args.chainId);
    break;

• src/toolService.js:121-133 (handler)

  ToolService handler that validates chainId, delegates to AgService.getLiquiditySources, and wraps the response with metadata.

  async getLiquiditySources(chainId) {
    if (!chainId) {
      throw new Error("chainId is required");
    }
  
    const result = await this.agg.getLiquiditySources(chainId);
  
    return {
      message: `Liquidity sources for chain ${chainId} retrieved successfully`,
      data: result,
      summary: `Found ${result.sources?.length || 0} liquidity sources`,
    };
  }

• src/services/agService.js:97-115 (handler)

  Core AgService handler implementing the HTTP fetch to the aggregator API endpoint /api/swap/sources.

  async getLiquiditySources(chainId) {
    try {
      const response = await fetch(`${this.baseUrl}/api/swap/sources?chainId=${chainId}`);
      
      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 liquidity sources: ${error.message}`);
    }
  }

• src/constants.js:8-8 (helper)

  Constant definition of the tool name used throughout the codebase.

  GET_LIQUIDITY_SOURCES: "get_liquidity_sources",