Best Practices
Expert tips for effective model testing, evaluation, and deployment.
Testing Strategy
1. Start Simple
✅ Begin with defaults:
- Temperature: 0.7
- Max Tokens: 500
- Single model (GPT-4o Mini)
Why: Establish a baseline before optimization.
2. Test Systematically
✅ Change one parameter at a time:
Test 1: Default settings
Test 2: Change temperature only
Test 3: Change max tokens only
Test 4: Combine best settings
❌ Don't: Change everything at once (can't identify what works).
3. Use Real Data
✅ Test with actual use case prompts:
- Real customer questions
- Actual data to analyze
- Production-like scenarios
✅ Leverage prompt history:
- Review what prompts worked before
- Re-run successful tests
- Track performance over time
❌ Don't: Only test with toy examples.
Sample Size
Minimum Test Runs
| Use Case | Min Tests | Why |
|---|---|---|
| Classification | 50 | Need statistical significance |
| Content Generation | 10 | Check consistency |
| Customer Support | 20 | Vary user intents |
| Data Analysis | 15 | Test edge cases |
Testing Pattern
// ✅ Good: Multiple runs
for (let i = 0; i < 20; i++) {
result = testModel(prompt, settings);
results.push(result);
}
analyze(results);
// ❌ Poor: Single test
result = testModel(prompt, settings);
deployToProduction(); // Risky!
Evaluation Criteria
Define Success Metrics
Before testing, define:
-
Quality Threshold
Customer Support: 90% helpful responses
Code Generation: 95% syntactically correct
Data Classification: 98% accuracy -
Performance Requirements
Response Time: < 2 seconds
Token Usage: < 500 tokens average
Cost per Request: < $0.01 -
Consistency Standard
Same input should yield similar quality
Variation acceptable: ±10%
Measure Objectively
Quantitative Metrics:
- Accuracy (for classification)
- Response time (milliseconds)
- Token count (cost proxy)
- Word count (length)
- Completion rate
Qualitative Assessment:
- Relevance (1-5 scale)
- Clarity (1-5 scale)
- Professionalism (1-5 scale)
- Accuracy (1-5 scale)
Model Selection
Decision Framework
1. Quality Requirements
High (>95%) → GPT-4 Omni
Medium (85-95%) → GPT-4o Mini
Basic (70-85%) → GPT-3.5 Turbo
2. Volume Considerations
Low (<1K/day) → Any model
Medium (1K-10K/day) → GPT-4o Mini or GPT-3.5
High (>10K/day) → GPT-3.5 Turbo + selective GPT-4
3. Budget Constraints
Premium → GPT-4 Omni
Standard → GPT-4o Mini
Economy → GPT-3.5 Turbo
Hybrid Approach
Best Practice: Use multiple models
function selectModel(request) {
// Complex reasoning → Premium model
if (requiresDeepAnalysis(request)) {
return "GPT-4-Omni";
}
// Standard questions → Mid-tier
if (isStandardQuery(request)) {
return "GPT-4o-Mini";
}
// Simple tasks → Economy
return "GPT-3.5-Turbo";
}
Parameter Optimization
Temperature Testing
Test at 3 points:
Low: 0.3
Medium: 0.7 (default)
High: 1.2
Choose based on:
- Consistency needed? → Use 0.3
- Balanced? → Use 0.7
- Creativity needed? → Use 1.2
Token Limit Optimization
Find the sweet spot:
// Test different limits
tokenLimits = [200, 400, 600, 800, 1000];
for (limit of tokenLimits) {
result = test({maxTokens: limit});
if (result.complete && result.cost < budget) {
optimalLimit = limit;
break;
}
}
Cost Management
Monitor Token Usage
Track these metrics:
metrics = {
avgInputTokens: 150,
avgOutputTokens: 300,
totalTokens: 450,
costPerRequest: 0.008,
requestsPerDay: 1000,
dailyCost: 8.00
}
Optimization Strategies
-
Prompt Optimization
❌ Verbose: "I would like you to please help me by..."
✅ Concise: "Summarize this text:"
Savings: 20-30% fewer input tokens -
Token Limits
❌ No limit: Average 800 tokens
✅ Set limit: 400 tokens
Savings: 50% on output costs -
Model Routing
❌ All GPT-4: $300/month
✅ Mixed models: $80/month
Savings: 73%
Quality Assurance
Pre-Deployment Checklist
- Tested with 20+ real prompts
- Success rate > threshold
- Response time acceptable
- Cost within budget
- Edge cases handled
- Error handling tested
- Monitoring in place
Continuous Testing
After deployment:
// Monitor production
setInterval(() => {
metrics = collectMetrics();
if (metrics.quality < threshold) {
alert("Quality degradation detected");
}
if (metrics.cost > budget) {
alert("Budget exceeded");
}
}, 3600000); // Check hourly
Common Mistakes
❌ Mistake 1: Testing Only Once
Problem: Single test doesn't show consistency
Solution: Run minimum 10 tests per configuration
❌ Mistake 2: Using Wrong Model
Problem: GPT-4 for simple classification (expensive)
Solution: Match model capability to task complexity
❌ Mistake 3: Ignoring Edge Cases
Problem: Works for normal inputs, fails on unusual ones
Solution: Test with:
- Empty inputs
- Very long inputs
- Special characters
- Multiple languages
- Ambiguous requests
❌ Mistake 4: No Cost Analysis
Problem: Production costs explode unexpectedly
Solution: Calculate costs before scaling:
Cost per Request × Requests per Day × 30 = Monthly Cost
❌ Mistake 5: Skipping Documentation
Problem: Can't reproduce or explain results
Solution: Document:
- Test configurations
- Success criteria
- Results and metrics
- Rationale for choices
Pro Tip: GenAI Explorer's prompt history automatically documents your tests! Export the history for comprehensive records.
Testing Template
Use This Structure
## Test: [Test Name]
**Date:** [Date]
**Tester:** [Name]
### Configuration
- Model: GPT-4o Mini
- Temperature: 0.7
- Max Tokens: 500
- Top P: 1.0
### Test Cases
1. [Test case 1]
- Input: [prompt]
- Expected: [expected output]
- Actual: [actual output]
- Pass/Fail: [result]
### Metrics
- Success Rate: 85%
- Avg Response Time: 1.8s
- Avg Cost: $0.006
- Token Usage: 450 avg
### Analysis
- Strengths: [what worked well]
- Weaknesses: [what didn't work]
- Recommendations: [next steps]
### Decision
[ ] Deploy as-is
[ ] Needs optimization
[ ] Try different model
Advanced Tips
1. A/B Testing
Test two approaches simultaneously:
Group A: GPT-4 Omni, temp 0.5
Group B: GPT-4o Mini, temp 0.7
Compare: Quality, Cost, Speed
Winner: Based on your priorities
2. Prompt Versioning
Track prompt iterations using the built-in prompt history:
v1.0: Original prompt → Saved in history
v1.1: Added examples → Compare with v1.0
v1.2: Clarified format → See improvement
v1.3: Optimized tokens (20% reduction) → Best version
GenAI Explorer automatically saves all versions - just browse your history to compare!
3. Automated Testing
// Run automated tests
testSuite = [
{prompt: "test1", expected: "result1"},
{prompt: "test2", expected: "result2"},
// ...
];
results = runTests(testSuite, model, settings);
report = generateReport(results);
Related Documentation
- Temperature Guide - Optimize creativity
- Parameters Reference - All settings
- Model Comparison - Choose wisely
- Cost Optimization - Reduce spending
- Sample Prompts - Templates
Follow these best practices to ensure successful AI model testing and deployment.