Comet
Comet provides Opik for language model and agent observability plus an MLOps suite for experiment tracking. You can self‑host open‑source Opik or use cloud-hosted tiers to collect traces, run evaluations, and inspect model and agent behavior with integrated test suites and metrics dashboards.
The linked official pages document an open-source Opik ($0) and free cloud tiers; MLOps Pro is listed at $19 per user/month. The Opik Pro Cloud numeric price and billing cadence are presented inconsistently on the pages.Is Comet right for you?
Good for
- Engineering teams that need end-to-end language model/agent observability, trace-based diagnostics, and integrated evaluation of prompts and agent runs.
- Opik is available as open-source you can self-host, giving you the same codebase as hosted versions.
- Comet documents a long-term free cloud offering and a free account option without a credit card requirement.
Keep in mind
- The default free cloud span data retention is limited to 60 days on the pricing page.
- Some Opik Connect and Ollie actions are listed as trial then paid (token purchase) rather than included free.
- Buyers requiring fully documented per-user cloud pricing for Opik Pro Cloud from public pages; confirm cloud billing terms and retention limits with Comet sales.
Pricing and plan limits
The linked official pages list Open Source and Free Cloud as free; MLOps Pro shows "$19 Per user/month". Opik Pro Cloud pricing and billing cadence are presented ambiguously on the sources and should be confirmed with Comet sales.
More about capabilities and limits
Documented strengths
Opik is available as open-source you can self-host, giving you the same codebase as hosted versions.
Comet documents a long-term free cloud offering and a free account option without a credit card requirement.
Limitations to consider
The default free cloud span data retention is limited to 60 days on the pricing page.
Some Opik Connect and Ollie actions are listed as trial then paid (token purchase) rather than included free.
Choosing a plan
Deploy Opik OSS or sign up for the free cloud tier, run representative agent traces and evaluations, and verify cloud retention, team limits, and any token-based paid features against your expected load.
Based on the linked product documentation.
Available on
Web.
Official sources
Alternatives to Comet
Choose around the work you need to do.
Langfuse
Use Langfuse for open‑source, self‑hostable tracing, prompt management, evaluations, and cost/latency visibility across model calls in developer-facing AI observability workflows.
