OpenLLMetry
An open-source set of OpenTelemetry extensions for standardised LLM observability.
OpenLLMetry, from Traceloop, extends OpenTelemetry, the industry standard for tracing, to cover LLM applications. Because the data is standard OTel, it flows into whatever observability backend you already run.
The pitch is no lock-in: instrument once with an open standard, and send the traces wherever you like.
Where it fits
A fit when you want LLM tracing as standard OpenTelemetry data, feeding an observability backend you already use.
Where it does not fit
An instrumentation layer, not a destination: you still need a backend to store and view the traces.
Alternatives to OpenLLMetry
The closest options on the map, and where each fits instead.
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Langfuse LLM observability
A strong default whenever an AI system reaches production and you need to see what it actually did, call by call.
Unlike OpenLLMetry Hosted APIMaturity: established
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Phoenix LLM observability
A fit when you want open, OpenTelemetry-based tracing and evaluation with a focus on debugging agent behaviour.
Unlike OpenLLMetry Source available
Pairs with
Commonly used alongside it.
