Helicone observes.
Runback re-executes.
Helicone is a zero-code proxy that logs every LLM call with a base-URL swap. Proxy capture only sees inputs and outputs — no tool chains, no re-execution, no compliance artifacts.
| Capability | Helicone | Runback | Note |
|---|---|---|---|
| Zero-code setup — base URL swap | ✓ | ✓ | Runback also offers proxy mode |
| Cost and token tracking | ✓ | ✓ | |
| Rate limiting and caching | ✓ | ✗ | Helicone speciality — not Runback's scope |
| Tool call capture (multi-step agents) | ✗ | ✓ | Proxy only sees the outer LLM call |
| Re-execute any step from captured inputs | ✗ | ✓ | |
| Policy simulation and enforcement | ✗ | ✓ | |
| Signed, tamper-evident audit export | ✗ | ✓ | |
| Self-host, data in your perimeter | partial | ✓ | Helicone self-host is limited |
Most teams use both — Heliconefor day-to-day trace browsing, Runback for incident replay, CI gating, and the compliance artifact. The two don't overlap until the moment an agent misbehaves in production and someone asks you to prove it.
Try the replay on a real incident.
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