Reddit Buddy MCP

Instructions

Implementation Reference

• src/tools/index.ts:285-384 (handler)

  The core handler function implementing the user_analysis tool logic. Fetches user profile, posts, and comments from Reddit API, handles time-based filtering with fallbacks, and processes the data into a summary using ContentProcessor.processUserSummary.

  async userAnalysis(params: z.infer<typeof userAnalysisSchema>) {
    // Try to get posts within the specified time range first
    // If time_range is 'all', use 'new' sort; otherwise use 'top' to respect time filtering
    const sort = params.time_range === 'all' ? 'new' : 'top';
    
    let posts = null;
    let comments = null;
    let usedFallback = false;
    
    const user = await this.api.getUser(params.username);
    
    // Fetch posts
    if (params.posts_limit > 0) {
      posts = await this.api.getUserPosts(params.username, 'submitted', {
        limit: params.posts_limit,
        sort,
        time: params.time_range,
      });
      
      // If no results with time filter, fallback to getting recent posts
      if (posts.data.children.length === 0 && params.time_range !== 'all') {
        usedFallback = true;
        posts = await this.api.getUserPosts(params.username, 'submitted', {
          limit: params.posts_limit,
          sort: 'new',
          time: 'all',
        });
      }
    }
    
    // Fetch comments
    if (params.comments_limit > 0) {
      comments = await this.api.getUserPosts(params.username, 'comments', {
        limit: params.comments_limit,
        sort,
        time: params.time_range,
      });
      
      // If no results with time filter, fallback to getting recent comments
      if (comments.data.children.length === 0 && params.time_range !== 'all') {
        usedFallback = true;
        comments = await this.api.getUserPosts(params.username, 'comments', {
          limit: params.comments_limit,
          sort: 'new',
          time: 'all',
        });
      }
    }
  
    // Process summary
    let summary: any;
    if (posts) {
      summary = ContentProcessor.processUserSummary(user, posts, {
        maxTopSubreddits: params.top_subreddits_limit,
        comments: comments || undefined
      });
    } else {
      // Fallback when no posts - but still include comments if available
      summary = {
        username: user.name,
        accountAge: 'Unknown',
        karma: {
          link: user.link_karma,
          comment: user.comment_karma,
          total: user.link_karma + user.comment_karma,
        },
      };
  
      // Add comments even when there are no posts
      if (comments && comments.data.children.length > 0) {
        summary.recentComments = comments.data.children.map(child => {
          const comment = child.data as any;
          return {
            id: comment.id,
            body: comment.body?.substring(0, 200) + (comment.body?.length > 200 ? '...' : ''),
            score: comment.score,
            subreddit: comment.subreddit || 'unknown',
            postTitle: comment.link_title,
            created: new Date(comment.created_utc * 1000),
            url: `https://reddit.com${comment.permalink}`,
          };
        });
      }
    }
  
    // Add note if we used fallback data
    if (usedFallback && params.time_range !== 'all') {
      const timeRangeLabel = {
        'hour': 'hour',
        'day': 'day',
        'week': 'week', 
        'month': 'month',
        'year': 'year'
      }[params.time_range];
      
      summary.timeRangeNote = `No posts found in the last ${timeRangeLabel}, showing all recent posts instead`;
    }
  
    return summary;
  }

• src/tools/index.ts:41-47 (schema)

  Zod schema defining the input parameters for the user_analysis tool, including username and optional limits for posts, comments, time range, and top subreddits.

  export const userAnalysisSchema = z.object({
    username: z.string().describe('Reddit username'),
    posts_limit: z.number().min(0).max(100).optional().default(10).describe('Default 10, range (0-100). Change ONLY IF user specifies.'),
    comments_limit: z.number().min(0).max(100).optional().default(10).describe('Default 10, range (0-100). Override ONLY IF user asks.'),
    time_range: z.enum(['day', 'week', 'month', 'year', 'all']).optional().default('month').describe('Time range for posts/comments (default: month). Note: When set to values other than "all", posts are sorted by top scores within that period. When set to "all", posts are sorted by newest'),
    top_subreddits_limit: z.number().min(1).max(50).optional().default(10).describe('Default 10, range (1-50). Change ONLY IF user requests.'),
  });

• src/mcp-server.ts:125-129 (registration)

  Registration of the user_analysis tool in the MCP server's toolDefinitions array, specifying name, description, input schema, and read-only hint.

    name: 'user_analysis',
    description: 'Analyze a Reddit user\'s posting history, karma, and activity patterns. Returns posts, comments, and statistics.',
    inputSchema: zodToJsonSchema(userAnalysisSchema) as any,
    readOnlyHint: true
  },

• src/mcp-server.ts:166-170 (registration)

  Dispatch logic in the MCP tool call handler that invokes the userAnalysis method with parsed arguments when 'user_analysis' is called.

  case 'user_analysis':
    result = await tools.userAnalysis(
      userAnalysisSchema.parse(args)
    );
    break;