note · growing
Vanilla vs agentic: the cost
Latency, tokens, complexity, accuracy, failure surface. The decision is that trade.
Agentic RAG wins on accuracy and costs real engineering effort in latency, tokens and failure surface. The decision is that trade.
| Dimension | Vanilla RAG | Agentic RAG |
|---|---|---|
| Latency | low, ~1–2 s | high and variable |
| Token cost | low, one query | high, history re-read each round |
| Complexity | a simple pipeline | state management + tool wiring |
| Accuracy on hard tasks | low, context breaks | high, cross-synthesis |
| Failure surface | narrow: search and generate | wide: planning, tools, loops |
Vanilla — typical request1 LLM calls
Agentic — typical request6 LLM calls
If you cannot measure the accuracy gain, the latency and tokens you pay are real and the gain is an assumption.