Respan
Nested traces for every LLM call, tool run, and agent turn
37 Best Promptfoo Alternatives & Competitors (2026)
The top alternatives to Promptfoo in the Observability, Prompts & Evals space, compared on features, pricing, and what they're best at.
Updated March 10, 2026
Why look beyond Promptfoo?
Promptfoo is an open-source tool for testing prompts, agents, and RAGs, with AI red teaming, pentesting, and vulnerability scanning for LLMs. Built under MIT license, Promptfoo was originally developed for LLM apps serving over 10 million users in production. The platform compares performance across GPT, Claude, Gemini, Llama, and more with simple declarative configs supporting command line and CI/CD integration. The Community version includes up to 10,000 probes monthly at no charge, with infrastructure costs typically USD 50-500 monthly for hosting and LLM API calls. Developers praise Promptfoo for its speed, quality-of-life features like live reloads and caching, security features including red teaming, and budget-friendly open-source model. However, the CLI-focused approach creates friction for non-technical team members, and the platform lacks end-to-end observability, version control for prompts, and test management features needed for complex production agents.
Common reasons users explore alternatives
- CLI-focused creates friction for non-technical users
- Limited observability for complex production agents
- No version control for prompts, data, or metrics
- Offline nature hits ceiling for production scale
Top alternatives to Promptfoo
LangSmith
Native tracing for LangChain and LangGraph
MLflow
OpenTelemetry-based tracing for LLMs and agents
Weights & Biases
ML experiment tracking
Arize AI
ML observability with LLM support
Langfuse
Tracing for LLM calls, tool runs, and agent steps
Datadog LLM
LLM monitoring within Datadog platform
Traceloop
OpenTelemetry
Helicone
Braintrust
Experiments comparing prompts and models
HoneyHive
Prompt management
Patronus AI
Automated LLM evaluation platform
Phoenix
OpenTelemetry-based LLM and agent tracing
Portkey
Humanloop
DeepEval
Ragas
RAG-specific evaluation framework
Sentry
Galileo AI
LLM output quality evaluation
LangWatch
Multi-turn agent simulation testing
PromptLayer
Confident AI
DeepEval open-source evaluation framework
Maxim AI
Distributed tracing for LLM and agent apps
Opik
Agenta
Future AGI
Multimodal evaluation (text, image, audio, video)
Lunary
Parea AI
Sentrial
Agent failure root cause analysis
Athina AI
Chamber
ML infrastructure automation
Moda
Hallucination detection
Ashr
Multi-modal synthetic testing
AgentOps
Session replay with time-travel debugging
Fiddler AI
Agentic observability across multi-step agent workflows
Laminar
Agent tracing with a readable transcript view
OpenObserve
Logs, metrics, traces, RUM, and session replay
Run Observability, Prompts & Evals in production with Respan
One platform for routing, observability, tracing, and evals across every LLM provider.
Compare Promptfoo alternatives with Respan
10KFree traces/mo
1,000+Models
5 minSetup
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.
Try Respan free