A agentindex
Comparison

Fiddler vs Comet Opik

A like-for-like, spec-level comparison. Both entries are verified against their docs and repo.

Fiddler

AI observability and governance for enterprise.

  • + Strong governance and compliance story
  • + Good for regulated enterprise
  • − Enterprise-priced
  • − Heavier than dev-focused tools

Comet Opik

Open-source eval and tracing from Comet.

  • + Open source with self-host option
  • + Backed by Comet's MLOps experience
  • − Smaller community than Langfuse
  • − UI less polished than paid rivals
Spec Fiddler Comet Opik
Category eval-observability eval-observability
License Proprietary Apache-2.0
Open source No Yes
Self-hostable No Yes
MCP support No No
Pricing paid freemium
Starting price Custom (enterprise) Self-host free
Models multi multi
Languages python python, typescript
GitHub stars — 19.8k
Last activity — 2026-06-25