Pub.dev MCP Server

Instructions

Implementation Reference

• src/pubdev-mcp.ts:271-303 (handler)

  The primary handler function that implements the get_package_info tool. It fetches package data from pub.dev API using caching, extracts relevant information into a structured PackageInfo object, and returns formatted JSON response.

  private async getPackageInfo(packageName: string) {
    const url = `https://pub.dev/api/packages/${packageName}`;
    const data = await this.fetchWithCache<any>(url, `package-${packageName}`);
  
    const packageInfo: PackageInfo = {
      name: data.name,
      version: data.latest.version,
      description: data.latest.pubspec?.description,
      homepage: data.latest.pubspec?.homepage,
      repository: data.latest.pubspec?.repository,
      publishedAt: data.latest.published,
      dependencies: data.latest.pubspec?.dependencies,
      devDependencies: data.latest.pubspec?.dev_dependencies
    };
  
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify({
            package: packageInfo,
            stats: {
              likes: data.likes,
              points: data.points,
              popularity: data.popularity
            },
            publishers: data.publishers,
            uploaders: data.uploaders
          }, null, 2)
        }
      ]
    };
  }

• src/pubdev-mcp.ts:63-76 (registration)

  Registration of the get_package_info tool in the ListToolsRequestHandler, including name, description, and input schema.

  {
    name: "get_package_info",
    description: "Get detailed information about a Dart/Flutter package from pub.dev",
    inputSchema: {
      type: "object",
      properties: {
        packageName: {
          type: "string",
          description: "Name of the package to retrieve information for"
        }
      },
      required: ["packageName"]
    }
  },

• src/pubdev-mcp.ts:14-23 (schema)

  TypeScript interface defining the output structure for package information used in the handler.

  interface PackageInfo {
    name: string;
    version: string;
    description?: string;
    homepage?: string;
    repository?: string;
    publishedAt: string;
    dependencies?: Record<string, string>;
    devDependencies?: Record<string, string>;
  }

• src/pubdev-mcp.ts:195-196 (handler)

  Dispatch case in the CallToolRequestHandler that routes calls to the getPackageInfo method.

  case "get_package_info":
    return await this.getPackageInfo(args.packageName as string);

• src/pubdev-mcp.ts:247-269 (helper)

  Helper method for fetching data from pub.dev with caching, used by the getPackageInfo handler.

  private async fetchWithCache<T>(url: string, cacheKey: string): Promise<T> {
    const cached = this.packageCache.get(cacheKey);
    const now = Date.now();
  
    if (cached && (now - cached.timestamp) < this.CACHE_DURATION) {
      return cached.data as T;
    }
  
    const response = await fetch(url, {
      headers: {
        'User-Agent': 'MCP-PubDev-Server/1.0.0',
        'Accept': 'application/json'
      }
    });
  
    if (!response.ok) {
      throw new Error(`HTTP ${response.status}: ${response.statusText}`);
    }
  
    const data = await response.json() as T;
    this.packageCache.set(cacheKey, { data, timestamp: now });
    return data;
  }