Respan
Nested traces for every LLM call, tool run, and agent turn
The top alternatives to DeepEval in the Observability, Prompts & Evals space, compared on features, pricing, and what they're best at.
Updated March 10, 2026
DeepEval is open-source framework for evaluating LLM outputs with metrics and test cases.
Respan
Nested traces for every LLM call, tool run, and agent turn
LangSmith
Native tracing for LangChain and LangGraph
MLflow
OpenTelemetry-based tracing for LLMs and agents
Weights & Biases
ML experiment tracking
Langfuse
Tracing for LLM calls, tool runs, and agent steps
Arize AI
ML observability with LLM support
Datadog LLM
LLM monitoring within Datadog platform
Helicone
Traceloop
OpenTelemetry
HoneyHive
Prompt management
Braintrust
Experiments comparing prompts and models
Patronus AI
Automated LLM evaluation platform
Promptfoo
Phoenix
OpenTelemetry-based LLM and agent tracing
Humanloop
Portkey
Sentry
Ragas
RAG-specific evaluation framework
Galileo AI
LLM output quality evaluation
LangWatch
Multi-turn agent simulation testing
PromptLayer
Maxim AI
Distributed tracing for LLM and agent apps
Confident AI
DeepEval open-source evaluation framework
Opik
Agenta
Lunary
Future AGI
Multimodal evaluation (text, image, audio, video)
Parea AI
Chamber
ML infrastructure automation
Athina AI
Moda
Hallucination detection
Ashr
Multi-modal synthetic testing
Sentrial
Agent failure root cause analysis
Laminar
Agent tracing with a readable transcript view
OpenObserve
Logs, metrics, traces, RUM, and session replay
Fiddler AI
Agentic observability across multi-step agent workflows
AgentOps
Session replay with time-travel debugging
One platform for routing, observability, tracing, and evals across every LLM provider.
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 1,000+ models through one gateway.
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