# Contracts
## Purpose
Design by contract implementation enforcing security boundaries and operational constraints throughout the system.
## Key Components
- **security.py**: Core security contracts with preconditions, postconditions, and invariants for all agent operations
## Architecture & Dependencies
**External**: contracts library for design by contract implementation
**Internal**: Boundaries module for cryptographic operations, validators for input checking, types system for security contexts
**Patterns**: Decorator pattern for contract enforcement, Observer pattern for violation handling
## Critical Considerations
- **Security**: All operations protected by comprehensive security contracts with audit trails
- **Performance**: O(1) contract checking with compiled validation rules for minimal overhead
- **Integration**: Seamless integration with all system components through decorator-based contracts
## Related Documentation
- [Security Framework Documentation](../../docs/security/SECURITY_FRAMEWORK.md)
- [Contract Implementation Guide](../contracts/security.py)
