Respan
Nested traces for every LLM call, tool run, and agent turn
Helicone is an open-source AI Gateway and LLM Observability platform that enables developers to route, debug, and analyze their AI applications with end-to-end visibility from user sessions to individual token decisions. As a Y Combinator-backed company, Helicone combines observability with infrastructure management, offering token-level cost analysis, prompt version tracking, and session tracing alongside intelligent routing features like caching, rate limiting, and load balancing. The platform provides real-time dashboards, user metrics tracking, alert systems, and multi-step LLM interaction visualization for root cause analysis. Helicone is SOC 2 Type II certified, HIPAA compliant, and offers flexible deployment options including cloud-hosted gateway leveraging Cloudflare's global network, self-hosted via Kubernetes Helm charts, or SDK-only observability without proxying.
What this tool does well, and the limitations to keep in mind.
Pros
Cons
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 1,000+ models through one gateway.
Try Respan freeTop companies in Observability, Prompts & Evals you can use instead of Helicone.
Respan
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Side-by-side comparisons with other tools in this category.
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