We indexed all of r/LangChain 2025 - you can now plug it directly into your agents via MCP
Reddit's official API, transparent process, and a free tool for your agents
So someone asked “is this legal?” on my last post here. Fair enough - let me be transparent about what we’re actually doing and why.
What we built
We created a searchable knowledge base from r/LangChain discussions using Reddit’s official API. No scraping, no bypassing anything. Properly authenticated, rate-limited, the whole deal.
The interesting part: we then built an MCP integration so you can plug this entire subreddit’s knowledge directly into your LangChain or LlamaIndex agents.
Why we built it
Honestly? This subreddit is one of the best sources of real-world LangChain knowledge out there. People here are actually shipping things in production - not just writing tutorials.
But the problem is discoverability. Great answers get buried. Solutions that took someone hours to figure out disappear into old threads.
We wanted to fix that.
How it actually works
Reddit API fetches posts + comments (official, authenticated)
Content gets stored in a Needle collection with metadata
You can search it directly OR plug it into your agents via MCP
What you can do with it
Search for things like:
Tool calling with function schemas
Multi-agent orchestration patterns
Vector store performance comparisons
Or build agents that query this knowledge directly while reasoning. Pretty useful when you’re debugging at 2am and don’t want to scroll through 50 threads.
Completely free, no signup required
Knowledge base: https://needle.app/featured-collections/reddit-langchain-2025
MCP guide: https://docs.needle.app/docs/guides/mcp/needle-mcp-server/
Curious what you all think - what topics would be most useful to have indexed? And what other subreddits should we do next?