The Experiment Layer for AI Products

Optimize for real business metrics, not just evals.
A/B test prompts, policies, and models in production measuring actual user behavior and product KPIs.

// Test two prompts against real users
const promptA = "answer {{support_chat_question}}"
const promptB = "answer {{support_chat_question}} giving step-by-step instructions"
const selectedPrompt = twotail.assign({
  variants: [promptA, promptB],
  weights: [0.5, 0.5],
  metrics: ["user_satisfaction"]
})
// ...
twotail.track("user_satisfaction", 4)
// Real-time results
User Satisfaction Score
Prompt A: 3.2/5
baseline
Prompt B: 4.1/5
+28% lift
✓ Statistical significance reached
✓ Winner: Prompt B

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Practical guides for AI product teams on A/B testing prompts and improving business outcomes

How to A/B Test Prompts (for AI Product Teams)

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10 Types of A/B Tests You Can Run to Optimize Your AI Product Prompts

Prompt optimization isn't just about clever wordsmithing - it's about running experiments that improve real business outcomes. Here are ten practical A/B test ideas AI product teams can try today.

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Prompt Optimization: What It Really Means for AI Products

Everyone talks about "prompt optimization" - but what does it actually mean when you're building an AI product? For product teams, it must mean something deeper: does this prompt improve the business?

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