MCP Server Chart

Instructions

Implementation Reference

• src/utils/generate.ts:56-82 (handler)

  The core handler function for map tools like generate_path_map. It sends the tool name and input parameters to an external visualization server via HTTP POST to generate the path map.

  export async function generateMap(
    tool: string,
    input: unknown,
  ): Promise<ResponseResult> {
    const url = getVisRequestServer();
  
    const response = await axios.post(
      url,
      {
        serviceId: getServiceIdentifier(),
        tool,
        input,
        source: "mcp-server-chart",
      },
      {
        headers: {
          "Content-Type": "application/json",
        },
      },
    );
    const { success, errorMessage, resultObj } = response.data;
  
    if (!success) {
      throw new Error(errorMessage);
    }
    return resultObj;
  }

• src/charts/path-map.ts:10-39 (schema)

  Defines the input schema (using Zod) and tool metadata for the generate_path_map tool, including name, description, and inputSchema.

  const schema = {
    title: MapTitleSchema,
    data: z
      .array(
        z.object({ data: POIsSchema }).describe("The route and places along it."),
      )
      .nonempty("At least one route is required.")
      .describe(
        'Routes, each group represents all POIs along a route. For example, [{ "data": ["西安钟楼", "西安大唐不夜城", "西安大雁塔"] }, { "data": ["西安曲江池公园", "西安回民街"] }]',
      ),
    width: MapWidthSchema,
    height: MapHeightSchema,
  };
  
  // https://modelcontextprotocol.io/specification/2025-03-26/server/tools#listing-tools
  const tool = {
    name: "generate_path_map",
    description:
      "Generate a route map to display the user's planned route, such as travel guide routes.",
    inputSchema: zodToJsonSchema(schema),
    annotations: {
      title: "Generate Path Map",
      readOnlyHint: true,
    },
  };
  
  export const pathMap = {
    schema,
    tool,
  };

• src/server.ts:64-77 (registration)

  Sets up MCP tool handlers. The listTools handler includes generate_path_map from Charts.pathMap.tool, and callTool requests are routed to the callTool utility.

  function setupToolHandlers(server: Server): void {
    logger.info("setting up tool handlers...");
    server.setRequestHandler(ListToolsRequestSchema, async () => ({
      tools: getEnabledTools().map((chart) => chart.tool),
    }));
  
    // biome-ignore lint/suspicious/noExplicitAny: <explanation>
    server.setRequestHandler(CallToolRequestSchema, async (request: any) => {
      logger.info("calling tool", request.params.name, request.params.arguments);
  
      return await callTool(request.params.name, request.params.arguments);
    });
    logger.info("tool handlers set up");
  }

• src/utils/callTool.ts:9-36 (helper)

  Maps the generate_path_map tool name to the 'path-map' chart type for dispatch.

  const CHART_TYPE_MAP = {
    generate_area_chart: "area",
    generate_bar_chart: "bar",
    generate_boxplot_chart: "boxplot",
    generate_column_chart: "column",
    generate_district_map: "district-map",
    generate_dual_axes_chart: "dual-axes",
    generate_fishbone_diagram: "fishbone-diagram",
    generate_flow_diagram: "flow-diagram",
    generate_funnel_chart: "funnel",
    generate_histogram_chart: "histogram",
    generate_line_chart: "line",
    generate_liquid_chart: "liquid",
    generate_mind_map: "mind-map",
    generate_network_graph: "network-graph",
    generate_organization_chart: "organization-chart",
    generate_path_map: "path-map",
    generate_pie_chart: "pie",
    generate_pin_map: "pin-map",
    generate_radar_chart: "radar",
    generate_sankey_chart: "sankey",
    generate_scatter_chart: "scatter",
    generate_treemap_chart: "treemap",
    generate_venn_chart: "venn",
    generate_violin_chart: "violin",
    generate_waterfall_chart: "waterfall",
    generate_word_cloud_chart: "word-cloud",
  } as const;

• src/utils/callTool.ts:70-80 (helper)

  Identifies generate_path_map as a map chart tool and delegates execution to generateMap.

  const isMapChartTool = [
    "generate_district_map",
    "generate_path_map",
    "generate_pin_map",
  ].includes(tool);
  
  if (isMapChartTool) {
    // For map charts, we use the generateMap function, and return the mcp result.
    const { metadata, ...result } = await generateMap(tool, args);
    return result;
  }