Reddit MCP Server

Instructions

Implementation Reference

• src/reddit-client.ts:160-163 (handler)

  Core handler function in RedditClient that fetches user's submitted posts from the Reddit API endpoint `/user/{username}/submitted`, maps the response data to RedditPost objects using mapPost.

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

• src/index.ts:61-65 (schema)

  Zod schema for runtime validation of input arguments to the get_user_posts tool.

  const GetUserPostsSchema = 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:178-204 (registration)

  Tool registration in the MCP listTools response, defining the tool's name, description, and JSON schema for inputs.

  {
    name: 'get_user_posts',
    description: 'Get posts submitted 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 posts',
          default: 'new',
        },
        limit: {
          type: 'number',
          description: 'Number of posts to retrieve (1-100)',
          minimum: 1,
          maximum: 100,
          default: 25,
        },
      },
      required: ['username'],
    },
  },

• src/index.ts:361-372 (handler)

  Dispatch handler in MCP callTool request that parses arguments with Zod schema and invokes the RedditClient.getUserPosts method, formats response as MCP content.

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