Reddit MCP Server

Instructions

Implementation Reference

• src/index.ts:374-385 (handler)

  MCP CallToolRequest handler implementation for the 'get_user_comments' tool. Parses arguments using Zod schema, calls RedditClient.getUserComments, and formats response as JSON text.

  case 'get_user_comments': {
    const args = GetUserCommentsSchema.parse(request.params.arguments);
    const comments = await redditClient.getUserComments(args.username, args.sort, args.limit);
    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(comments, null, 2),
        },
      ],
    };
  }

• src/index.ts:67-71 (schema)

  Zod schema for validating input parameters of the get_user_comments tool: username (required string), sort (enum: hot/new/top, default 'new'), limit (1-100, default 25).

  const GetUserCommentsSchema = z.object({
    username: z.string().min(1, "Username is required"),
    sort: z.enum(['hot', 'new', 'top']).default('new'),
    limit: z.number().min(1).max(100).default(25),
  });

• src/index.ts:205-231 (registration)

  Tool registration in ListToolsResponse: defines name, description, and inputSchema matching the Zod schema.

  {
    name: 'get_user_comments',
    description: 'Get comments made by a user',
    inputSchema: {
      type: 'object',
      properties: {
        username: {
          type: 'string',
          description: 'Reddit username (without u/ prefix)',
        },
        sort: {
          type: 'string',
          enum: ['hot', 'new', 'top'],
          description: 'Sort order for comments',
          default: 'new',
        },
        limit: {
          type: 'number',
          description: 'Number of comments to retrieve (1-100)',
          minimum: 1,
          maximum: 100,
          default: 25,
        },
      },
      required: ['username'],
    },
  },

• src/reddit-client.ts:165-168 (helper)

  Core implementation in RedditClient: makes authenticated API request to Reddit's /user/{username}/comments endpoint and maps responses to RedditComment objects using mapComment helper.

  async getUserComments(username: string, sort: 'hot' | 'new' | 'top' = 'new', limit: number = 25): Promise<RedditComment[]> {
    const data = await this.makeRequest(`/user/${username}/comments?sort=${sort}&limit=${limit}`);
    return data.data.children.map((child: any) => this.mapComment(child.data));
  }

• src/reddit-client.ts:219-230 (helper)

  Helper method to transform raw Reddit API comment data into structured RedditComment interface.

  private mapComment(data: any): RedditComment {
    return {
      id: data.id,
      author: data.author,
      body: data.body,
      created_utc: data.created_utc,
      score: data.score,
      permalink: `https://reddit.com${data.permalink}`,
      parent_id: data.parent_id,
      subreddit: data.subreddit,
    };
  }