Helicone

Helicone is an open-source tool that helps you watch and understand how your AI agents talk to large language models. You send your model calls through Helicone’s proxy, and it records each request and response without changing the result. A clear web dashboard then shows logs, latency, token counts, error rates, and cost for every call. You can filter, search, and trace a single user journey, which makes it easy to spot slow prompts or rising costs. Helicone also lets you set alerts and share traces with your team, so problems get fixed fast and future changes are safer.