reddit-mcp-server

Instructions

Implementation Reference

• src/index.ts:420-436 (registration)

  Registration of the 'get_trending_subreddits' MCP tool, including inline handler (execute function), schema (empty parameters), and description. The handler fetches trending subreddits using the Reddit client and returns a formatted markdown list.

  server.addTool({
    name: "get_trending_subreddits",
    description: "Get a list of currently trending subreddits",
    parameters: z.object({}),
    execute: async () => {
      const client = getRedditClient()
      if (!client) {
        throw new Error("Reddit client not initialized")
      }
  
      const trendingSubreddits = await client.getTrendingSubreddits()
  
      return `# Trending Subreddits
  
  ${trendingSubreddits.map((subreddit, index) => `${index + 1}. r/${subreddit}`).join("\n")}`
    },
  })

• src/index.ts:424-435 (handler)

  Inline execute handler function for the get_trending_subreddits tool that initializes Reddit client, calls getTrendingSubreddits, and formats the result as a numbered list in markdown.

    execute: async () => {
      const client = getRedditClient()
      if (!client) {
        throw new Error("Reddit client not initialized")
      }
  
      const trendingSubreddits = await client.getTrendingSubreddits()
  
      return `# Trending Subreddits
  
  ${trendingSubreddits.map((subreddit, index) => `${index + 1}. r/${subreddit}`).join("\n")}`
    },

• src/client/reddit-client.ts:277-293 (helper)

  Supporting method in RedditClient class that authenticates and fetches popular subreddits from Reddit API endpoint /subreddits/popular.json, returning array of subreddit names used as trending subreddits.

  async getTrendingSubreddits(limit: number = 5): Promise<string[]> {
    await this.authenticate()
    try {
      const params = new URLSearchParams({ limit: limit.toString() })
      const response = await this.makeRequest(`/subreddits/popular.json?${params}`)
  
      if (!response.ok) {
        throw new Error(`HTTP ${response.status}`)
      }
  
      const json = (await response.json()) as { data: { children: any[] } }
      return json.data.children.map((child: any) => child.data.display_name)
    } catch {
      // Failed to get trending subreddits
      throw new Error("Failed to get trending subreddits")
    }
  }