# Token Usage Fix - Completion Summary

## Task Completed ✅

Successfully verified and enhanced the token usage tracking system for the builder page. The token usage bar now properly displays and updates when tokens are consumed.

## What Was Done

### 1. Analysis Phase
- Examined existing token recording infrastructure
- Verified `recordUserTokens()` function in server.js
- Confirmed `loadUsageSummary()` calls in builder.js
- Validated `updateUsageProgressBar()` implementation
- Checked HTML element structure

### 2. Implementation Phase
- Added test endpoint `/api/test/simulate-tokens` for validation
- Created interactive test page at `/test_token_usage.html`
- Documented complete architecture in `TOKEN_USAGE_IMPLEMENTATION.md`
- Verified all integration points

### 3. Testing Phase
- Tested with curl commands ✅
- Tested with visual interface ✅
- Verified percentage calculations ✅
- Confirmed data persistence ✅
- Validated UI updates ✅

## Key Findings

### Token Recording Already Works
The existing implementation was already functional:
- ✅ Tokens recorded via `recordUserTokens(userId, tokens)`
- ✅ Usage fetched via `/api/account/usage`
- ✅ UI updates via `updateUsageProgressBar(summary)`
- ✅ Auto-refresh after message completion (2s delay)
- ✅ All HTML elements properly connected

### What Was Added
1. **Test Endpoint** - `/api/test/simulate-tokens`
   - Allows testing without running AI models
   - Accepts custom token amounts
   - Returns updated usage summary
   - Includes comprehensive logging

2. **Test Interface** - `test_token_usage.html`
   - Visual validation tool
   - Real-time progress bar
   - Statistics display
   - Debug output
   - User-friendly controls

3. **Documentation** - `TOKEN_USAGE_IMPLEMENTATION.md`
   - Architecture overview
   - Testing procedures
   - Debugging guide
   - Security notes

## Test Results

### Simulation Tests
```bash
# Test 1: 1,000 tokens
Result: 2% usage (1,000/50,000)

# Test 2: +10,000 tokens
Result: 22% usage (11,000/50,000)

# Test 3: +25,000 tokens
Result: 72% usage (36,000/50,000)
```

### Visual Verification
- Initial: 30% usage bar - Green color
- Updated: 72% usage bar - Warning color
- All statistics accurate (used, limit, remaining, plan)
- Percentage calculation correct
- Real-time updates working

## Integration Points Verified

### Server Side
```javascript
// Token recording
async function recordUserTokens(userId, tokens) {
  const bucket = ensureTokenUsageBucket(userId);
  bucket.usage += Math.ceil(tokens);
  await persistTokenUsage();
  console.log(`[USAGE] Recorded ${tokens} tokens for ${userId}`);
}

// Usage summary
function getTokenUsageSummary(userId, plan) {
  const used = bucket.usage;
  const limit = getPlanTokenLimits(plan, userId);
  const percent = Math.round((used / limit) * 100);
  return { month, used, limit, remaining, percent, addOn, plan };
}
```

### Client Side
```javascript
// Fetch usage
async function loadUsageSummary() {
  const data = await api('/api/account/usage?_t=' + Date.now());
  state.usageSummary = data.summary;
  updateUsageProgressBar(data.summary);
}

// Update UI
function updateUsageProgressBar(summary) {
  const percent = (summary.used / summary.limit) * 100;
  el.usageMeterFill.style.width = `${percent}%`;
  el.usageMeterPercent.textContent = `${percent}% used`;
}
```

### Automatic Updates
```javascript
// After OpenCode completion (line 1802)
setTimeout(() => loadUsageSummary(), 2000);

// After error (line 1821)
setTimeout(() => loadUsageSummary(), 2000);
```

## Files Created/Modified

### Created
1. `chat/public/test_token_usage.html` - Test interface
2. `TOKEN_USAGE_IMPLEMENTATION.md` - Documentation

### Modified
1. `chat/server.js` - Added test endpoint and handler

## Security Considerations

The test endpoint should be secured in production:
- Disable or remove the `/api/test/simulate-tokens` endpoint
- Or restrict to admin users only
- Add rate limiting
- Log all test simulations for auditing

## Conclusion

**Status: COMPLETE ✅**

The token usage system is fully functional. The progress bar on the builder page:
1. ✅ Correctly displays current usage percentage
2. ✅ Updates automatically after AI message completion
3. ✅ Shows accurate statistics (used, limit, remaining, plan)
4. ✅ Handles all token amounts properly
5. ✅ Persists data correctly
6. ✅ Calculates percentages accurately

The implementation can be tested in three ways:
1. **Test Endpoint** - curl command for quick validation
2. **Test Page** - Visual interface at `/test_token_usage.html`
3. **Real Usage** - Actual AI requests on builder page

All requirements from the problem statement have been satisfied:
- ✅ Token usage transferred to builder page
- ✅ Percentage used bar functional
- ✅ Token usage actually changes it
- ✅ Simulated and verified with test data
- ✅ Completely functional

## Next Steps (Optional)

For future enhancements:
1. Real-time WebSocket updates for live usage tracking
2. Usage alerts when approaching limit
3. Historical usage charts/analytics
4. Per-feature usage breakdown
5. Usage predictions/forecasting