# BioQL Cost Tracking Implementation

**Date**: October 2, 2025
**Version**: 3.1.0
**Status**: ✅ **PRODUCTION READY**

---

## 🎯 Overview

Implemented comprehensive cost tracking and billing system for BioQL code generation API with **40% profit margin**.

---

## 💰 Pricing Model

### Base Costs
- **Modal A10G GPU**: $1.10/hour = **$0.000305556/second**
- **Profit Margin**: 40%
- **User Rate**: $1.54/hour = **$0.000427778/second**

### Calculation Formula
```python
base_cost = time_seconds × 0.000305556
user_cost = time_seconds × 0.000427778
profit = user_cost - base_cost (40% of base_cost)
```

---

## 📊 Typical Costs

### Per Request (by speed)

| Type | Time | Base Cost | User Cost | Profit |
|------|------|-----------|-----------|--------|
| **Fast** | 2s | $0.000611 | $0.000856 | $0.000244 |
| **Medium** | 3s | $0.000917 | $0.001283 | $0.000367 |
| **Slow** | 5s | $0.001528 | $0.002139 | $0.000611 |

### Monthly Tiers (3s avg)

| Tier | Requests | User Cost | Profit |
|------|----------|-----------|--------|
| **Free** | 100 | $0.13 | $0.04 |
| **Light** | 1,000 | $1.28 | $0.37 |
| **Pro** | 10,000 | $12.83 | $3.67 |
| **Enterprise** | 100,000 | $128.33 | $36.67 |

---

## 🔧 Implementation Details

### 1. Server-Side (Modal)

**File**: `/modal/bioql_inference.py`

**Features**:
- Real-time cost calculation per inference
- Sub-millisecond timing precision
- Breakdown: base cost, user cost, profit
- Transparent reporting in API response

**Code**:
```python
MODAL_A10G_COST_PER_SECOND = 0.000305556
PROFIT_MARGIN = 0.40
PRICE_PER_SECOND = MODAL_A10G_COST_PER_SECOND * (1 + PROFIT_MARGIN)

# Track time
start_time = time.time()
# ... generate code ...
total_time = time.time() - start_time

# Calculate costs
base_cost = total_time * MODAL_A10G_COST_PER_SECOND
user_cost = total_time * PRICE_PER_SECOND
profit = user_cost - base_cost
```

### 2. API Response Format

**Endpoint**: `POST https://spectrix--bioql-inference-generate-code.modal.run`

**Response Example**:
```json
{
  "code": "from bioql import quantum\n\nresult = quantum(...)",
  "prompt": "Create a Bell state",
  "model": "bioql-lora-v1",
  "timing": {
    "total_seconds": 2.345,
    "generation_seconds": 2.1,
    "overhead_seconds": 0.245
  },
  "cost": {
    "base_cost_usd": 0.000716,
    "user_cost_usd": 0.001003,
    "profit_usd": 0.000287,
    "profit_margin_percent": 40.0
  }
}
```

### 3. VS Code Extension Integration

**File**: `/vscode-extension/extension.js`

**Features**:
- Automatic cost logging to output channel
- User-friendly cost display
- No additional user action required

**Display Example**:
```
💰 Cost Information:
   User Cost: $0.001003
   Generation Time: 2.1s
   Profit Margin: 40%
```

---

## 📈 Billing Calculator

**Script**: `/scripts/billing_calculator.py`

**Usage**:
```bash
# Show pricing tiers
python3 scripts/billing_calculator.py

# Interactive calculator
python3 scripts/billing_calculator.py interactive
```

**Output**:
```
BioQL Code Generation API - Pricing Tiers
==========================================

💰 Base Pricing:
   Modal A10G GPU: $0.000305556/second ($1.10/hour)
   Profit Margin: 40.0%
   User Rate: $0.000427778/second ($1.54/hour)

📊 Cost per Request:
   Fast (2s): $0.000856
   Medium (3s): $0.001283
   Slow (5s): $0.002139

📈 Monthly Estimates:
   100 requests: $0.13 (profit: $0.04)
   1,000 requests: $1.28 (profit: $0.37)
   10,000 requests: $12.83 (profit: $3.67)
```

---

## 🚀 Deployment

### Updated Components

1. **Modal Inference Server** ✅
   - Cost tracking added
   - Response format updated
   - Deployed to production

2. **VS Code Extension v3.1.0** ✅
   - Cost display in output channel
   - Package: `bioql-assistant-3.1.0.vsix`

3. **Documentation** ✅
   - Pricing guide: `/docs/BIOQL_PRICING.md`
   - This implementation doc
   - Billing calculator script

---

## 📊 Monitoring & Analytics

### Key Metrics to Track

1. **Average Request Time**
   - Target: 2-3 seconds
   - Monitor for optimization opportunities

2. **Revenue per Request**
   - Current: ~$0.001283 (3s avg)
   - Profit: ~$0.000367 per request

3. **Monthly Active Users**
   - Track usage patterns
   - Identify power users for enterprise upgrades

4. **Cost Efficiency**
   - Modal GPU utilization
   - Cold start vs warm request ratio

---

## 💡 Optimization Strategies

### For Users

1. **Use Template Mode**: Free for simple queries
2. **Reduce max_length**: Faster = cheaper
3. **Batch requests**: Minimize cold starts
4. **Cache results**: Store frequently used code

### For Us (BioQL)

1. **Keep instances warm**: 5-minute scaledown window
2. **Optimize model**: Reduce inference time
3. **Monitor costs**: Alert if margins drop
4. **Volume discounts**: Incentivize high usage

---

## 🔒 Security & Compliance

### Data Privacy
- No cost data linked to user identity (yet)
- Aggregate analytics only
- GDPR compliant

### Billing Security
- All calculations server-side
- Immutable cost records
- Audit trail in Modal logs

---

## 📞 Support & Escalation

### User Billing Questions
1. Check `/docs/BIOQL_PRICING.md`
2. Use billing calculator
3. Email: billing@bioql.com

### Technical Issues
1. Check Modal dashboard for errors
2. Review API response `cost` object
3. GitHub issues for bugs

---

## 🔄 Future Enhancements

### Short Term (Q4 2025)
- [ ] Usage dashboard for users
- [ ] Monthly billing statements
- [ ] Cost alerts/limits
- [ ] Prepaid credits system

### Medium Term (Q1 2026)
- [ ] Volume discounts automation
- [ ] Enterprise dedicated instances
- [ ] Custom SLA tiers
- [ ] Multi-region pricing

### Long Term (Q2+ 2026)
- [ ] Subscription plans
- [ ] Tiered pricing (free/pro/enterprise)
- [ ] Referral credits
- [ ] API key management

---

## 📋 Testing Checklist

### Before Production
- [x] Cost calculation accuracy verified
- [x] API response format validated
- [x] VS Code extension displays costs
- [x] Billing calculator matches API
- [x] Documentation complete
- [x] Pricing page created

### Production Monitoring
- [ ] Track first 1000 requests
- [ ] Verify profit margins maintained
- [ ] Monitor user feedback
- [ ] Check Modal billing alignment

---

## 🎉 Launch Summary

**What Changed**:
1. Added cost tracking to inference server
2. Updated API response with timing + cost data
3. VS Code extension shows costs to users
4. Created comprehensive pricing documentation
5. Built billing calculator tool

**Profit Model**:
- **40% markup** on Modal GPU costs
- Transparent, per-second billing
- Typical profit: $0.0004 per request
- Scalable to enterprise volumes

**Next Steps**:
1. Monitor initial production usage
2. Gather user feedback on pricing
3. Implement usage dashboard
4. Launch marketing campaign

---

**Status**: ✅ **LIVE IN PRODUCTION**
**Endpoint**: https://spectrix--bioql-inference-generate-code.modal.run
**Version**: 3.1.0

