Nobody mentions this upfront: the frameworks cost almost nothing. Everything else destroys your budget. Spent 3 weeks optimizing the wrong stuff before I figured this out.
LangChain: Free Code, Expensive Everything Else
LangChain is MIT licensed, works fine for prototypes. But if you want to ship something that doesn't crash, you need LangSmith for debugging.
Where it gets fucked:
- Free tier: 5,000 traces/month (lasted us 2 days)
- Paid: $39/user/month plus overages
- Three of us: started cheap, bill got ugly
Their trace counting makes no sense. One conversation spawned dozens of traces. Simple chatbot queries somehow generating 40+ traces. Blew through free limit in 2 days.
First month hit us for $687. Could've been more - stopped tracking after it hurt.
LlamaIndex: Credit Roulette
LlamaIndex uses credits instead of traces. Thought this would be simpler. Wrong. Their pricing docs are confusing as hell.
Credits vanish fast:
- Document indexing burned 200k credits for our knowledge base
- Query operations cost 15-40 credits for no reason
- Free tier: 10,000 credits (gone in 6 days)
RAG app hit 200 queries/day, forced us onto $500/month Pro tier. Credit math is random - same query costs different amounts. Complex queries burn 100+ credits and you only find out after. Their Discord is mostly people bitching about surprise usage.
Credit system screws you over. Document processing destroys credits. Spent hours reading docs, still can't predict costs.
CrewAI: Execution Roulette
CrewAI's pricing is fucked. They charge per "crew execution" but nobody explains what that means. Docs are useless for execution counting.
Pricing cliff murders your budget:
- Basic: $99/month (100 executions)
- Standard: $500/month (1,000 executions) - 5x jump
- No middle option, no overage plan
Hit Basic limit in 10 days then boom - $500/month. No warning. Went from $99 to $500 overnight.
Multi-agent workflows eat multiple "executions" for one task. Simple workflow might count as 1 execution, might be 3. Complex ones trigger 5-8 internal executions for no reason. Black box. Can't plan capacity.
The Real Killers: What Nobody Mentions
Platform fees are nothing. Here's what destroys your budget:
LLM API Costs - Multi-agent systems are chatty as hell. Burned through $743 in OpenAI costs in 3 weeks. Agents love talking to each other, using way more tokens than makes sense. 200-token task becomes 15k+ tokens somehow.
Infrastructure - Pinecone starts at $70/month but you'll hit $280 fast. AWS hosting runs us $1,100/month and that's optimized. Add monitoring, logging, alerts - another $400/month.
Your Sanity - Took 3 months to get anything working in prod. These frameworks break in weird ways. Spent 2 weeks debugging CrewAI memory leaks. LangChain randomly fails on certain queries for no reason.
Bottom line: frameworks are 5% of total costs. Real money goes to OpenAI bills, AWS hosting, and debugging at 3am.