Token Usage & Cost Monitoring
Measure how many tokens your agents consume and what they cost in real time, set budgets, and find the expensive steps so you can optimize spend in production.
Why Track Tokens and Cost
Agents that loop, retry, or use long context can quietly become expensive. Without visibility you only discover the bill at month end.
Token and cost monitoring turns spend into a metric you can watch, alert on, and optimize.
Prompt vs Completion Tokens
Every call splits into:
- Prompt tokens: everything you send in (system prompt, context, history)
- Completion tokens: what the model generates
They are usually priced differently, so track them separately.
All lessons in this course
- LangSmith for Tracing & Monitoring
- Debugging Agent Thought Processes
- Evaluating Agent Performance
- Token Usage & Cost Monitoring