Arize Phoenix
A self-hostable AI observability workspace for inspecting traces, replaying model calls, managing prompts, and comparing experiments on shared datasets.
✓ Free optionFree to self-host; infrastructure extra
Coding & App Builders
Langfuse
An AI engineering platform connecting application traces, cost and latency metrics, prompt versions, datasets, and evaluation results.
What it does
An AI engineering platform connecting application traces, cost and latency metrics, prompt versions, datasets, and evaluation results.
Who it is for
Engineering teams combining AI observability and prompt iteration across frameworks.
What stands out
- Model, retrieval, and tool-call traces
- Prompt versioning linked to application runs
- Evaluations, datasets, and experiment comparisons
Limitations to consider
- Hosted usage is billed in Langfuse units, not a flat price per end-user conversation.
- Data access periods and enterprise controls vary by tier.
Integrations & connections
Tasks it can help with
Sources & verification
This profile is based on vendor documentation, checked Sep 19, 2026. It is not a hands-on review or a performance benchmark. Unknown details are marked explicitly.
Platform documentationOfficial pricingObservability documentationSuggest a correctionRead before you decide
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