reddit-mcp-server

Instructions

Implementation Reference

• src/index.ts:371-418 (handler)

  Primary handler implementation for the 'get_subreddit_info' tool: validates input with Zod schema, fetches data via RedditClient, formats with formatSubredditInfo, and returns comprehensive markdown summary.

  server.addTool({
    name: "get_subreddit_info",
    description: "Get detailed information about a subreddit including description, stats, and community analysis",
    parameters: z.object({
      subreddit_name: z.string().describe("The subreddit name (without r/ prefix)"),
    }),
    execute: async (args) => {
      const client = getRedditClient()
      if (!client) {
        throw new Error("Reddit client not initialized")
      }
  
      const subreddit = await client.getSubredditInfo(args.subreddit_name)
      const formattedSubreddit = formatSubredditInfo(subreddit)
  
      return `# Subreddit Information: r/${formattedSubreddit.name}
  
  ## Overview
  - Name: r/${formattedSubreddit.name}
  - Title: ${formattedSubreddit.title}
  - Subscribers: ${formattedSubreddit.stats.subscribers.toLocaleString()}
  - Active Users: ${
        typeof formattedSubreddit.stats.activeUsers === "number"
          ? formattedSubreddit.stats.activeUsers.toLocaleString()
          : formattedSubreddit.stats.activeUsers
      }
  
  ## Description
  ${formattedSubreddit.description.short}
  
  ## Detailed Description
  ${formattedSubreddit.description.full}
  
  ## Metadata
  - Created: ${formattedSubreddit.metadata.created}
  - Flags: ${formattedSubreddit.metadata.flags.join(", ")}
  
  ## Links
  - Subreddit: ${formattedSubreddit.links.subreddit}
  - Wiki: ${formattedSubreddit.links.wiki}
  
  ## Community Analysis
  - ${formattedSubreddit.communityAnalysis.replace(/\n  - /g, "\n- ")}
  
  ## Engagement Tips
  - ${formattedSubreddit.engagementTips.replace(/\n  - /g, "\n- ")}`
    },
  })

• src/client/reddit-client.ts:157-184 (helper)

  RedditClient method that authenticates and fetches raw subreddit data from Reddit's API endpoint /r/{subredditName}/about.json, parsing into RedditSubreddit type.

  async getSubredditInfo(subredditName: string): Promise<RedditSubreddit> {
    await this.authenticate()
    try {
      const response = await this.makeRequest(`/r/${subredditName}/about.json`)
      if (!response.ok) {
        throw new Error(`HTTP ${response.status}`)
      }
  
      const json = (await response.json()) as RedditApiSubredditResponse
      const data = json.data
  
      return {
        displayName: data.display_name,
        title: data.title,
        description: data.description || "",
        publicDescription: data.public_description || "",
        subscribers: data.subscribers,
        activeUserCount: data.active_user_count ?? undefined,
        createdUtc: data.created_utc,
        over18: data.over18,
        subredditType: data.subreddit_type,
        url: data.url,
      }
    } catch {
      // Failed to get subreddit info
      throw new Error(`Failed to get subreddit info for ${subredditName}`)
    }
  }

• src/utils/formatters.ts:244-274 (helper)

  Helper function that processes raw RedditSubreddit data into a rich formatted structure including stats, descriptions, metadata, links, community analysis, and engagement tips.

  export function formatSubredditInfo(subreddit: RedditSubreddit): FormattedSubredditInfo {
    const flags: string[] = []
    if (subreddit.over18) flags.push("NSFW")
    if (subreddit.subredditType) flags.push(`Type: ${subreddit.subredditType}`)
  
    const ageDays = (Date.now() / 1000 - subreddit.createdUtc) / (24 * 3600)
  
    return {
      name: subreddit.displayName,
      title: subreddit.title,
      stats: {
        subscribers: subreddit.subscribers,
        activeUsers: subreddit.activeUserCount !== undefined ? subreddit.activeUserCount : "Unknown",
      },
      description: {
        short: subreddit.publicDescription,
        full:
          subreddit.description.length > 300 ? subreddit.description.substring(0, 297) + "..." : subreddit.description,
      },
      metadata: {
        created: formatTimestamp(subreddit.createdUtc),
        flags: flags.length ? flags : ["None"],
      },
      links: {
        subreddit: `https://reddit.com${subreddit.url}`,
        wiki: `https://reddit.com/r/${subreddit.displayName}/wiki`,
      },
      communityAnalysis: analyzeSubredditHealth(subreddit.subscribers, subreddit.activeUserCount, ageDays),
      engagementTips: getSubredditEngagementTips(subreddit),
    }
  }