Reddit Data API — MCP Server

Access Reddit post submissions, comment threads, subreddit metrics, and search results programmatically. Built for AI agents, autonomous workflows, and applications requiring real-time Reddit data extraction without browser automation.

This MCP server provides a Model Context Protocol interface to Reddit's public data, enabling AI systems to query subreddit information, fetch posts sorted by hot/new/top/rising, retrieve comment trees, and search by keyword. All data returns as structured JSON suitable for immediate parsing, sentiment analysis pipelines, or database ingestion.

Features

• Subreddit Intelligence — Fetch metadata including subscriber count, active user estimates, creation date, description, and NSFW classification
• Post Extraction — Retrieve posts from any public subreddit with configurable sorting (hot, new, top, rising)
• Comment Thread Retrieval — Fetch complete comment trees from any Reddit post with nested reply structure
• Keyword Search — Search Reddit posts by query with time filters (hour, day, week, month, year, all) and sort options (relevance, hot, top, new, comments)
• MCP Protocol Compatible — Full Model Context Protocol implementation with initialize, tools/list, and tools/call methods
• Legacy Fallback Support — Accepts older { "tool": "...", "params": {...} } format for backward compatibility
• Structured JSON Output — All responses return parseable JSON with consistent field names
• No Browser Automation — Direct API calls ensure reliable performance without DOM parsing or page rendering overhead

Quick Start

# Install dependencies
npm install

# Test with subreddit info
echo '{"tool": "get_subreddit_info", "params": {"subreddit": "technology"}}' | INPUT_STORE=1 apify run

# Test with posts
echo '{"tool": "get_posts", "params": {"subreddit": "artificial", "sort": "hot", "limit": 10}}' | INPUT_STORE=1 apify run

# Test with comments
echo '{"tool": "get_comments", "params": {"postId": "1a2b3c", "subreddit": "technology"}}' | INPUT_STORE=1 apify run

# Test with search
echo '{"tool": "search_reddit", "params": {"query": "machine learning", "sort": "relevance", "time": "month"}}' | INPUT_STORE=1 apify run

Input

The actor accepts input as JSON via stdin or the key-value store. All parameters are optional unless required by the tool being called.

Parameter	Type	Required	Description
tool	string	Yes	Tool name: get_subreddit_info, get_posts, get_comments, search_reddit
params	object	Yes	Tool-specific parameters (see table below)

Tool Parameters

Tool	Parameter	Type	Required	Description
get_subreddit_info	subreddit	string	Yes	Subreddit name without r/ prefix
get_posts	subreddit	string	Yes	Subreddit name without r/ prefix
get_posts	sort	string	No	Sort order: hot (default), new, top, rising
get_posts	limit	number	No	Number of posts to fetch, default 25, max 100
get_comments	postId	string	Yes	Reddit post ID (6-character alphanumeric)
get_comments	subreddit	string	Yes	Subreddit name for context
search_reddit	query	string	Yes	Search keyword or phrase
search_reddit	sort	string	No	Sort: relevance (default), hot, top, new, comments
search_reddit	time	string	No	Time filter: hour, day, week, month, year, all
search_reddit	subreddit	string	No	Limit search to specific subreddit
search_reddit	limit	number	No	Number of results, default 25, max 100

Tools

Tool	Description	Price
get_subreddit_info	Returns subreddit metadata: name, title, description, subscriber count, active users, creation timestamp, NSFW flag, and banner image URL	$0.03
get_posts	Returns array of post objects with title, author, score, upvote ratio, created timestamp, URL, num comments, and post ID. Supports hot/new/top/rising sort	$0.03
get_comments	Returns nested comment tree with author, body, score, created timestamp, parent ID, and depth level. Handles MoreComments objects	$0.05
search_reddit	Returns search results matching query with post metadata. Includes time filter and sort options for result prioritization	$0.05

Output

All tools return structured JSON with consistent formatting:

{
  "success": true,
  "tool": "get_subreddit_info",
  "data": {
    "name": "technology",
    "title": "Technology",
    "description": "...",
    "subscribers": 15000000,
    "activeUsers": 50000,
    "createdAt": 1192400700,
    "nsfw": false
  },
  "meta": {
    "processingTimeMs": 145,
    "redditRateLimitRemaining": 98
  }
}

Error responses follow the same structure with success: false and an error field:

{
  "success": false,
  "tool": "get_posts",
  "error": "Subreddit not found",
  "code": "SUBREDDIT_INVALID"
}

Pricing

This actor runs on Apify Cloud and uses pay-per-performance pricing. Each tool invocation costs a fixed amount regardless of result count:

Tool	Price per call
get_subreddit_info	$0.03
get_posts	$0.03
get_comments	$0.05
search_reddit	$0.05

Minimum cost per run: $0.03. Costs accumulate based on the number of tool calls made during actor execution.

Troubleshooting

"Subreddit not found" error Verify the subreddit name is spelled correctly and does not include the r/ prefix. Example: use technology not r/technology.

Empty results for valid search query Reddit search has rate limits. Wait 30 seconds between searches. If problem persists, the subreddit may be restricted or the query may violate Reddit's content policies.

Comments returned are collapsed or limited Some posts have thousands of comments. The actor returns the first 500 nested comments to avoid excessive response sizes. Use the limit parameter to control depth.

Rate limit errors (HTTP 429) Reddit imposes per-IP rate limits. Reduce request frequency. For high-volume use cases, consider running multiple actor instances with different IP addresses via Apify Proxy.

Post ID format confusion Reddit post IDs are 6-character alphanumeric strings found in the URL: reddit.com/r/technology/comments/abc123/... The post ID is abc123.

Build and Deploy

# Verify syntax
node --check src/main.js

# Push to Apify Cloud
apify push

# Run remotely
apify run

License

MIT