The rows worth reading.
Helicone is a proxy-based LLM gateway that sits between your app and the LLM API, recording cost and latency data. It's useful for quick cost tracking but is not an observability platform — no agent identity, no delegation tracking, no evaluations, and no multi-agent support. As of mid-2025, Helicone has been reported to be in maintenance mode, with users actively seeking alternatives. Zespan offers the full picture.
| Zespan | Helicone | |
|---|---|---|
| Architecture | SDK + OTel ingest | Proxy (single point of failure) |
| Free tier | 10K traces/month | 100K req/month (7-day retention) |
| Starting price | $39/month | $25/month (Pro) |
| Active development | Active | Maintenance mode |
| Multi-agent tracing | Full delegation graph | Not available |
| Agent auto-discovery | Not available | |
| Agent health scoring | Not available | |
| Span waterfall | Full hierarchy | Not available |
| Evaluations | 12 templates, auto | Not available |
| Guardrails | 7 types | Not available |
| Cost forecasting | 30-day OLS forecast | Not available |
| AI cost optimizer | Not available | |
| Natural language query | ZespanPilot | Not available |
Which one fits
Pick Zespan when
You need real agent observability, not just cost logging.
Your system has multiple agents — delegation, handoffs, planning steps.
You want evaluations, guardrails, or runtime safety.
You can't afford a single point of failure in your LLM call path.
You want a platform that is actively developed and growing.
Pick Helicone when
You only need basic cost and latency tracking for a single LLM endpoint.
You want a proxy-based approach with no SDK code changes at all.
You're on a legacy system where instrumenting with an SDK is not possible.
Common questions
What does 'maintenance mode' mean for Helicone users?
Users have reported that Helicone's feature development has slowed significantly. New agent-observability capabilities are not being added. Zespan is actively developed with new features shipping regularly.
Is a proxy architecture a problem?
Proxies add latency to every LLM call and create a single point of failure. If the proxy is down, your LLM calls fail. Zespan uses an async SDK — traces are sent in the background without blocking or adding latency to your LLM calls.
Can I migrate from Helicone to Zespan?
Yes. Remove the Helicone proxy URL and replace with Zespan's SDK wrapper (e.g., wrapOpenAI()). You get the same cost and latency data plus full agent traces, evaluations, and guardrails.
Does Zespan track cost like Helicone does?
Yes — and more. Zespan tracks cost per call, per agent, per user, per operation, and per model. It also forecasts 30-day spend and generates AI-powered recommendations to cut costs.