MCP Server Chart

Instructions

Implementation Reference

• src/charts/fishbone-diagram.ts:1-72 (schema)

  Defines the Zod schemas for input validation (FishboneNodeSchema and main schema) and the tool metadata (name, description, inputSchema) for the generate_fishbone_diagram tool.
  import { z } from "zod"; import { zodToJsonSchema } from "../utils"; import { type TreeDataType, validatedTreeDataSchema } from "../utils/validator"; import { HeightSchema, TextureSchema, ThemeSchema, WidthSchema } from "./base"; // Fishbone node schema // The recursive schema is not supported by gemini, and other clients, so we use a non-recursive schema which can represent a tree structure with a fixed depth. // Ref: https://github.com/antvis/mcp-server-chart/issues/155 // Ref: https://github.com/antvis/mcp-server-chart/issues/132 export const FishboneNodeSchema: z.ZodType<TreeDataType> = z.object({ name: z.string(), children: z .array( z.object({ name: z.string(), children: z .array( z.object({ name: z.string(), children: z .array( z.object({ name: z.string(), }), ) .optional(), }), ) .optional(), }), ) .optional(), }); // Fishbone diagram input schema const schema = { data: FishboneNodeSchema.describe( "Data for fishbone diagram chart which is a hierarchical structure, such as, { name: 'main topic', children: [{ name: 'topic 1', children: [{ name: 'subtopic 1-1' }] }] }, and the maximum depth is 3.", ).refine(validatedTreeDataSchema, { message: "Invalid parameters: node name is not unique.", path: ["data"], }), style: z .object({ texture: TextureSchema, }) .optional() .describe( "Style configuration for the chart with a JSON object, optional.", ), theme: ThemeSchema, width: WidthSchema, height: HeightSchema, }; // Fishbone diagram tool descriptor const tool = { name: "generate_fishbone_diagram", description: "Generate a fishbone diagram chart to uses a fish skeleton, like structure to display the causes or effects of a core problem, with the problem as the fish head and the causes/effects as the fish bones. It suits problems that can be split into multiple related factors.", inputSchema: zodToJsonSchema(schema), annotations: { title: "Generate Fishbone Diagram", readOnlyHint: true, }, }; export const fishboneDiagram = { schema, tool, };
• src/utils/callTool.ts:9-36 (registration)

  CHART_TYPE_MAP registers the tool name 'generate_fishbone_diagram' to the internal chart type 'fishbone-diagram', enabling dispatch to the correct schema and generator.
  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:44-111 (handler)

  The core handler function that executes generate_fishbone_diagram: maps name to type, validates arguments using the chart-specific schema, generates the chart URL via generateChartUrl, and returns the MCP tool result.
  export async function callTool(tool: string, args: object = {}) { logger.info(`Calling tool: ${tool}`); const chartType = CHART_TYPE_MAP[tool as keyof typeof CHART_TYPE_MAP]; if (!chartType) { logger.error(`Unknown tool: ${tool}`); throw new McpError(ErrorCode.MethodNotFound, `Unknown tool: ${tool}.`); } try { // Validate input using Zod before sending to API. // Select the appropriate schema based on the chart type. const schema = Charts[chartType].schema; if (schema) { // Use safeParse instead of parse and try-catch. const result = z.object(schema).safeParse(args); if (!result.success) { logger.error(`Invalid parameters: ${result.error.message}`); throw new McpError( ErrorCode.InvalidParams, `Invalid parameters: ${result.error.message}`, ); } } 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; } const url = await generateChartUrl(chartType, args); logger.info(`Generated chart URL: ${url}`); return { content: [ { type: "text", text: url, }, ], _meta: { description: "This is the chart's spec and configuration, which can be renderred to corresponding chart by AntV GPT-Vis chart components.", spec: { type: chartType, ...args }, }, }; // biome-ignore lint/suspicious/noExplicitAny: <explanation> } catch (error: any) { logger.error( `Failed to generate chart: ${error.message || "Unknown error"}.`, ); if (error instanceof McpError) throw error; if (error instanceof ValidateError) throw new McpError(ErrorCode.InvalidParams, error.message); throw new McpError( ErrorCode.InternalError, `Failed to generate chart: ${error?.message || "Unknown error."}`, ); } }
• src/server.ts:64-77 (registration)

  Registers the MCP tool request handlers: lists all chart tools dynamically from Charts exports (including fishbone-diagram.tool), and handles tools/call by delegating to callTool with the tool name.
  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"); }