YouTube MCP Server

Instructions

Implementation Reference

• src/youtube-service.ts:94-119 (handler)

  Core implementation of fetching YouTube video comments using the YouTube Data API v3 commentThreads.list endpoint. This is the primary logic executed by the tool.

  async getComments(
    videoId: string,
    maxResults: number = 20,
    options: {
      order?: 'time' | 'relevance';
      pageToken?: string;
      includeReplies?: boolean;
    } = {}
  ): Promise<youtube_v3.Schema$CommentThreadListResponse> {
    try {
      const { order = 'relevance', pageToken, includeReplies = false } = options;
  
      const response = await this.youtube.commentThreads.list({
        part: includeReplies ? ['snippet', 'replies'] : ['snippet'],
        videoId,
        maxResults,
        order,
        pageToken
      });
  
      return response.data;
    } catch (error) {
      console.error('Error getting comments:', error);
      throw error;
    }
  }

• src/index.ts:265-299 (registration)

  MCP server.tool registration for 'get-video-comments', including input schema validation with Zod and the tool handler function that delegates to YouTubeService.getComments and formats the response.

  server.tool(
    'get-video-comments',
    'Retrieve comments for a specific YouTube video with sorting options',
    {
      videoId: z.string().min(1),
      maxResults: z.number().min(1).max(100).optional(),
      order: z.enum(['time', 'relevance']).optional(),
      includeReplies: z.boolean().optional(),
      pageToken: z.string().optional()
    },
    async ({ videoId, maxResults = 20, order = 'relevance', includeReplies = false, pageToken }) => {
      try {
        const commentsData = await youtubeService.getComments(videoId, maxResults, {
          order,
          includeReplies,
          pageToken
        });
  
        return {
          content: [{
            type: 'text',
            text: JSON.stringify(commentsData, null, 2)
          }]
        };
      } catch (error) {
        return {
          content: [{
            type: 'text',
            text: `Error fetching comments: ${error}`
          }],
          isError: true
        };
      }
    }
  );

• src/index.ts:268-274 (schema)

  Zod schema defining input parameters for the get-video-comments tool: videoId (required), optional maxResults, order, includeReplies, and pageToken.

  {
    videoId: z.string().min(1),
    maxResults: z.number().min(1).max(100).optional(),
    order: z.enum(['time', 'relevance']).optional(),
    includeReplies: z.boolean().optional(),
    pageToken: z.string().optional()
  },