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LangWatch logo
LangWatch
✓ verifiedFreemium

Platform to test, evaluate and observe LLM and voice AI agents, with prompt management and red-teaming for production.

23K visits/mo6.4K saves
metaflow.org logo
metaflow.org
✓ verifiedFree

Open-source Python framework, born at Netflix, for building, scaling, and deploying real-world ML, AI, and data science workflows.

20K visits/mo
honeyhive.ai logo
honeyhive.ai
✓ verifiedFreemium

Observability and evaluation platform for production LLM agents, built on OpenTelemetry for tracing, monitoring and testing.

24K visits/mo
Weights & Biases logo
Weights & Biases
✓ verifiedFreemium

Weights & Biases is a widely used MLOps platform for experiment tracking, model management and evaluating AI applications.

2.5M visits/mo
Arize AI logo
Arize AI
✓ verifiedFreemium

AI observability and evaluation platform to trace, evaluate and improve LLM agents in production, with an open-source Phoenix core.

248K visits/mo
Pricing
Developer: €0 (50k events/mo)
Growth: €29/core-seat/mo (+ €5 per 100k events)

No public pricing

Developer: $0 (10K events/month, up to 5 users, 30-day retention)

No public pricing

AX Free: $0/mo (25k spans/mo)
AX Pro: $50/mo (50k spans/mo)
Core features
  • Scenario-based agent testing
  • LLM evaluation and quality scoring
  • Observability for cost and latency
  • Prompt management with GitHub sync
  • Voice AI simulation
  • LLM red-teaming and governance
  • Plain-Python workflow orchestration
  • Automatic versioning and experiment tracking
  • Scale-out compute with GPUs and parallel instances
  • One-command deployment to production
  • Runs on AWS, Azure, GCP, or Kubernetes
  • Event-based triggering of workflows
  • OpenTelemetry-native distributed tracing across 100+ LLMs and frameworks
  • Online evaluation via LLM-as-a-judge or code
  • Offline experiments and regression detection
  • Annotation queues for expert review
  • Alerts and drift detection
  • Prompt management, CLI and docs MCP server
  • Experiment tracking and visualization for ML training runs
  • Model and artifact versioning and management
  • Hyperparameter optimization tooling
  • Collaborative dashboards and reports for ML teams
  • LLM application tracing and evaluation tooling
  • Agent and LLM tracing
  • Large-scale evaluations
  • Open-source Phoenix observability
  • Alyx AI engineering agent
  • OpenTelemetry-based instrumentation
  • Experiments and prompt playgrounds
Use cases
  • Catch agent issues before production
  • Evaluate and monitor LLM quality
  • Test voice AI agents at scale
  • Developing and debugging ML pipelines locally
  • Scaling model training to cloud GPUs
  • Deploying experiments to production unchanged
  • Building reactive, event-driven data systems
  • Debugging multi-agent systems
  • Monitoring live agent quality at scale
  • Catching regressions before release
  • Human review of edge cases
  • Aligning automated evaluators with domain experts
  • ML engineers tracking and comparing training experiments
  • Research teams versioning datasets and model checkpoints
  • Teams building and evaluating LLM-powered applications
  • Organizations collaborating on machine learning projects
  • Debugging AI agents in production
  • Measuring LLM output quality
  • Catching regressions before deploy
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