Moda vs Promptfoo
Updated March 27, 2026
Overview
Turns agent conversations and tool traces into actionable signals — detects hallucinations, tool-call failures, prompt injections, and user frustration.
Promptfoo is an open-source tool for testing and evaluating LLM prompts. It lets developers define test cases, run them against multiple models, compare outputs side-by-side, and catch regressions before deployment. Supports custom scoring functions, red-teaming, and CI/CD integration for automated prompt testing.
Key features
Core capabilities each platform advertises.
- Hallucination detection
- Tool-call failure monitoring
- Prompt injection detection
- User frustration signals
- Actionable trace analysis
Strengths and tradeoffs
What each tool does well, and the limitations to keep in mind.
Pros
- Clear Datadog-for-agents positioning that is easy to understand
- Both founders have direct AI agent production experience at Shopify and Notion
- Plain-language signal definition is a strong differentiator vs code-heavy eval tools
- Built-in security monitoring for prompt injection and jailbreaks at no extra config
- Agent replay and batch testing enable rapid debugging of production failures
Cons
- Only 2 people with no disclosed pricing, revenue, or customers
- Crowded observability space with Arize, Braintrust, LangSmith, and Datadog expanding
- No public pricing may slow self-serve developer adoption
- Detection confidence of 87-94% means some failures still slip through
Pros
- Completely free and open source (MIT license)
- Fast with quality features like live reloads and caching
- Built-in red teaming and security vulnerability scanning
- Trusted by large companies with strong community
Cons
- 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
Moda or Promptfoo — which should you choose?
Choose Moda if you wantChoose if you want
- Agent conversation monitoring
- Safety detection
- User experience optimization
- Trace analysis
Choose Promptfoo if you wantChoose if you want
Compare Moda and Promptfoo on your own traffic
Respan lets you trace LLM and agent calls across any model or framework, A/B test prompts on production traffic, and route requests across 500+ models through one gateway.