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Fiddler AI logo
Fiddler AI
✓ verifiedFreemium

Enterprise AI observability and security platform to monitor, evaluate, and govern agentic and ML systems with guardrails.

51K visits/mo
liteLLM logo
liteLLM
✓ verifiedFreemium

Open-source AI gateway giving dev teams unified access, fallbacks and spend tracking across 100+ LLMs.

703K visits/mo
portkey.ai logo
portkey.ai
✓ verified

AI gateway and observability suite for governing and optimizing LLM apps; strong dev-tool traffic.

266K visits/mo
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
Pricing
Free: $0 (real-time guardrails)
Developer: $0.002 per trace
Open Source: $0 (self-hosted, 100+ providers)

Free trial available

No public pricing

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

No public pricing

Core features
  • End-to-end agentic and ML observability
  • Real-time guardrails (hallucination, PII, jailbreak)
  • Continuous evaluations and custom judges
  • Root-cause analysis and decision lineage
  • AI governance, risk, and compliance controls
  • Flexible SaaS, VPC, or on-prem deployment
  • Unified access to 100+ LLMs in OpenAI format
  • Cost/spend tracking per key, user and team
  • Budgets and rate limiting
  • Automatic provider fallbacks and retries
  • Virtual keys and team management
  • Logging and observability integrations
  • AI Gateway for reliable LLM routing
  • Prompt Engineering for collaborative prompt management
  • Guardrails for enforcing reliable LLM behavior
  • Observability Suite for monitoring costs, quality, and latency
  • MCP Client for building AI agents with real-world tool access
  • 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
Use cases
  • Monitoring production AI agents
  • Enforcing safety guardrails on LLM apps
  • Evaluating and debugging model behavior
  • Governance and compliance for enterprise AI
  • Giving developers governed access to many LLMs
  • Attributing and controlling LLM spend
  • Keeping apps running during provider outages
  • Monitor costs, quality, and latency of AI applications.
  • Route to 250+ LLMs reliably with a single endpoint.
  • Streamline and scale prompt engineering.
  • Enforce reliable LLM behavior with guardrails.
  • Build agents with access to real-world tools.
  • 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
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