# System Reminder Solution for @mentions

## Design Principles

1. **Keep it Simple**: No complex async operations
2. **Don't Modify Input**: Preserve original user message
3. **Append Only**: Add system-reminders at the end
4. **Synchronous**: Use require() instead of import()

## Implementation

```typescript
// Simple pattern matching
const mentions = input.match(/@[\w\-\.\/]+/g) || []

// Generate reminders without modifying input
for (const mention of mentions) {
  // Simple agent detection
  if (isLikelyAgent(name)) {
    reminders.push(agentReminder)
  } else if (existsSync(filePath)) {
    reminders.push(fileReminder)
  }
}

// Append reminders to message
processedInput = processedInput + '\n\n' + reminders.join('\n')
```

## How It Works

### For @file mentions:
- User types: `@improvements_summary.md`
- System adds reminder: "You should read the file at: /path/to/improvements_summary.md"
- AI sees the reminder and uses Read tool
- Agent loop continues normally

### For @agent mentions:
- User types: `@code-reviewer`
- System adds reminder: "Consider using the Task tool with subagent_type='code-reviewer'"
- AI sees the reminder and may invoke the agent
- Agent loop continues normally

## Why This Works

1. **No Flow Interruption**: Synchronous execution preserves message flow
2. **Original Input Intact**: User's message isn't modified
3. **Simple Logic**: No complex async imports or checks
4. **Agent Loop Safe**: Messages flow through without breaking

## Difference from Previous Approach

### Previous (Broken):
- Complex async operations
- Modified user input (removed @mentions)
- Multiple async imports
- 70+ lines of complex logic
- Broke agent loop

### Current (Working):
- Simple synchronous checks
- Preserves user input
- Uses require() not import()
- ~40 lines of simple logic
- Agent loop works properly

## Testing

You can test with:
- `@improvements_summary.md summarize this` - should read file
- `@code-reviewer check my code` - should suggest agent
- `@src/commands.ts explain this` - should handle paths

The agent should continue executing multiple rounds without interruption.