How much does an agent cost to run?
Agents are expensive because each task is many LLM calls with a growing context. Caching and a memory store are the levers.
10,000 requests / month · 12000/2000 in/out · 5,000 docs · 400 tok/doc · 70% cached
LLM API
$4.18 /moQwen3.7 Flashvia Alibaba
The big cost. Multi-step loops multiply token use - a cheaper model or aggressive caching changes the bill by 2-3x.
next: DeepSeek V4 Flash 0731 $4.28compare all ↗
◈ or self-host: 1× RTX 3090 at ~30% GPU use $85/mo· pays off above ~203K requests/mo
Vector DB
$0.02 /moZilliz Cloud (Serverless)via Zilliz
Agent memory / tool retrieval. Small unless the agent stores a lot.
next: turbopuffer $0.03compare all ↗
Observability
$0 /moArize Phoenix
Tracing is non-negotiable for agents - you can't debug what you can't see.
next: Helicone $0compare all ↗
Total, your workload≈ $4.21 /mo
Tune it for your numbers ↗ Live prices, updated 2026-09-15. A model, not a quote - each layer is priced at its cheapest provider; embeddings amortise the initial index over 12 months. Confirm on each provider's site.