Open sourcePython · ≈7.5k stars · Apache-2.0
OpenLLMetry
OpenTelemetry-based observability for LLM and agent applications.
OpenLLMetry is a set of extensions on top of OpenTelemetry that instrument LLM providers and vector databases, plus a Traceloop SDK that starts tracing with one init call. Because it emits standard OpenTelemetry data it connects to existing backends — the README lists Traceloop, Axiom, Azure Application Insights, Braintrust, Dash0, Datadog, Dynatrace, Google Cloud and more. Its semantic conventions have been contributed to OpenTelemetry. Built by Traceloop; a JS/TS version lives in openllmetry-js.
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stanfordnlp/dspy
Programming, not prompting: optimize the whole pipeline.
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langfuse/langfuse
Open-source LLM engineering platform: traces, evals, prompts.
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Connections
Relations from the Harness Hub knowledge graph, as charted in the State of Harness reports.
Sources
Verified Oct 29, 2026