LLM Observability
Platforms for tracing, evaluating and monitoring LLM and agent applications in production: span-level traces of model calls and tool use, offline and online evals, prompt versioning, and cost and latency telemetry. Distinct from AI SRE tools, which point AI at conventional infrastructure rather than observing the model layer.
LLM Observability Grid
Market Presence vs. Satisfaction
Langfuse
Open-source LLM engineering platform, now part of ClickHouse
Arize Phoenix
Open-source tracing and evals from an ML-observability incumbent
Comet Opik
Open-source evals and tracing from the experiment-tracking incumbent
DeepEval
Open-source LLM evaluation framework, pytest-shaped
W&B Weave
LLM tracing inside the experiment-tracking platform teams already run
Helicone
One-line proxy logging for LLM calls
OpenLLMetry
OpenTelemetry-native LLM tracing
AgentOps
Session replay and tracing built for agents, not chat calls
LangWatch
Open-source monitoring, evals and prompt optimisation
LLM Observability Rankings
Based on public metrics across brand authority, community, and reviews
| Rank | Tool | Score | Position | Brand | Community | Reviews | Sentiment | Pricing |
|---|---|---|---|---|---|---|---|---|
| 1 • | Langfuse | 62.0 | Leader | 72.0 | 95.0 | 0.0 | 70.0 | Free tier |
| 2 • | Arize Phoenix | 55.7 | Leader | 70.0 | 82.0 | 0.0 | 65.0 | Free tier |
| 3 • | Comet Opik | 54.9 | Leader | 66.0 | 88.0 | 0.0 | 66.0 | Free tier |
| 4 • | DeepEval | 47.3 | Leader | 52.0 | 85.0 | 0.0 | 60.0 | Free tier |
| 5 • | W&B Weave | 44.7 | Leader | 64.0 | 45.0 | 0.0 | 55.0 | Free tier |
| 6 • | Helicone | 42.7 | High Performer | 48.0 | 71.0 | 0.0 | 62.0 | Free tier |
| 7 • | OpenLLMetry | 42.4 | High Performer | 46.0 | 74.0 | 0.0 | 58.0 | Free tier |
| 8 • | AgentOps | 39.2 | High Performer | 42.0 | 68.0 | 0.0 | 56.0 | Free tier |
| 9 • | LangWatch | 35.5 | High Performer | 38.0 | 62.0 | 0.0 | 52.0 | Free tier |