Cargo Doc MCP Server

Instructions

Implementation Reference

• src/doc-manager.ts:284-325 (handler)

  Core handler function that traverses the Rust documentation directory, parses symbol files, and returns a list of SymbolInfo objects including name, type, path, and URL.

  public async listSymbols(projectPath: string, crateName: string): Promise<SymbolInfo[]> {
      const isBuilt = await this.checkDoc(projectPath, crateName);
      if (!isBuilt) {
          throw new DocError(
              DocErrorCode.SEARCH_FAILED,
              'Failed to access documentation'
          );
      }
  
      const cached = await this.cache.get(projectPath, crateName);
      if (!cached) {
          throw new DocError(
              DocErrorCode.CACHE_ERROR,
              'Cache error: Documentation entry not found'
          );
      }
  
      try {
          const { docPath } = cached;
          const docDir = path.dirname(docPath);
          const symbols: SymbolInfo[] = [];
  
          // 定义符号收集处理函数
          const symbolHandler = async (fileName: string, filePath: string, modulePath: string) => {
              const symbol = this.parseSymbolFromFile(fileName, modulePath, crateName, filePath);
              if (symbol) {
                  symbols.push(symbol);
              }
          };
  
          // 使用通用的traverseDirectory收集符号
          await this.traverseDirectory(docDir, crateName, '', symbolHandler);
  
          return symbols.sort((a, b) => a.path.localeCompare(b.path));
      } catch (error) {
          throw new DocError(
              DocErrorCode.SEARCH_FAILED,
              'Failed to list symbols',
              error
          );
      }
  }

• src/index.ts:109-122 (schema)

  Input schema definition for the list_symbols tool, specifying project_path and crate_name as required string parameters.

  inputSchema: {
    type: "object",
    properties: {
      project_path: {
        type: "string",
        description: "Path to the Rust project (must be absolute path)",
      },
      crate_name: {
        type: "string",
        description: "Name of the crate to list symbols for",
      },
    },
    required: ["project_path", "crate_name"],
  },

• src/index.ts:106-123 (registration)

  Tool registration in the ListTools response, defining name, description, and input schema.

  {
    name: "list_symbols",
    description: "List all symbols in a crate. Use when implementing traits or exploring available types. Shows structs, enums, traits with their paths.",
    inputSchema: {
      type: "object",
      properties: {
        project_path: {
          type: "string",
          description: "Path to the Rust project (must be absolute path)",
        },
        crate_name: {
          type: "string",
          description: "Name of the crate to list symbols for",
        },
      },
      required: ["project_path", "crate_name"],
    },
  },

• src/types.ts:51-56 (schema)

  Type definition for SymbolInfo, used as the return type of listSymbols.

  export interface SymbolInfo {
      name: string;
      type: SymbolType;
      path: string;
      url: string;
  }

• src/doc-manager.ts:219-237 (helper)

  Helper function to parse individual symbol information from documentation HTML file names.

  private parseSymbolFromFile(fileName: string, modulePath: string, crateName: string, filePath: string): SymbolInfo | null {
      const match = fileName.match(/^(struct|enum|trait|fn|const|type|macro|mod)\.(.+)\.html$/);
      if (!match) {
          return null;
      }
  
      const [, type, name] = match;
      const symbolName = name.replace(/-/g, '::');
      const fullPath = modulePath
          ? `${crateName}::${modulePath}::${symbolName}`
          : `${crateName}::${symbolName}`;
  
      return {
          name: symbolName,
          type: type as SymbolType,
          path: fullPath,
          url: RustdocUrl.create(filePath)
      };
  }