Flakestorm vs LangSmith

Comparing proactive testing with reactive observability

Quick Comparison

FeatureFlakestormLangSmith
Primary PurposeProactive testing before deploymentReactive observability and monitoring in production
PricingOpen-source (free) + Cloud plans ($49-$299/month)Paid SaaS service based on usage
Best ForFinding vulnerabilities before production, robustness validationUnderstanding what happened in production, debugging issues
TimingTests agents in development and CI/CD pipelinesMonitors agents after deployment
MethodActively attacks agents with adversarial inputsTracks traces, logs, and metrics from production usage
OutputRobustness score and pass/fail matrix before productionTraces, analytics, and debugging information
FocusFinding vulnerabilities and proving reliabilityUnderstanding what happened in production
Cost ModelOpen-source version is free, runs locallyPaid SaaS service based on usage
IntegrationCLI tool, CI/CD integration, local testingSDK integration, cloud-based platform
Data CollectionNo data sent (open-source), optional cloud analyticsCollects all traces and logs from production
Question Answered"Will my agent break?" (proactive)"Why did my agent break?" (reactive)

Complementary Tools

Flakestorm and LangSmith serve different purposes and work best together. They are not competitors but complementary tools in your AI agent development workflow.

Use Flakestorm For:

  • Testing agents before deployment
  • Finding vulnerabilities in development
  • Validating robustness in CI/CD
  • Getting mathematical proof of reliability
  • Blocking PRs when scores drop

Use LangSmith For:

  • Monitoring agents in production
  • Debugging production issues
  • Analyzing trace data
  • Understanding user interactions
  • Performance optimization

Flakestorm Advantages

  • Prevents issues before they reach production
  • Open-source version is completely free
  • Runs locally without sending data to external services
  • Provides mathematical robustness scores
  • Automatic adversarial mutation generation
  • CI/CD integration to block problematic code

LangSmith Advantages

  • Real-time production monitoring
  • Detailed trace analysis
  • Team collaboration features
  • Integration with LangChain ecosystem
  • Performance analytics and dashboards
  • Production debugging tools

Recommended Workflow

1

Development Phase

Use Flakestorm to test your agent with adversarial inputs and validate robustness before committing code.

2

CI/CD Pipeline

Integrate Flakestorm to block PRs when robustness scores drop below threshold.

3

Production Deployment

Deploy with confidence knowing Flakestorm validated your agent's robustness.

4

Production Monitoring

Use LangSmith to monitor traces, debug issues, and optimize performance in production.