Always include clear documentation for important code decisions and metadata. This includes preserving copyright notices and explaining the reasoning behind specific values and constants. For copyright notices: - Maintain all original copyright information - Add new copyright notices on separate lines, never replacing existing ones For code constants and values: - Replace hard-coded "magic numbers" with named constants - Add comments explaining the reasoning behind specific values, especially for timeouts, limits, and other non-obvious choices Example: ```go // Original hard-coded value svr.rc.VhostTcpMuxer, err = vhost.NewTcpHttpTunnelMuxer(l, 30*time.Second) // Improved version with named constant and explanation // DefaultTunnelTimeout defines how long to wait before closing inactive connections // 30 seconds was chosen based on average connection usage patterns const DefaultTunnelTimeout = 30 * time.Second svr.rc.VhostTcpMuxer, err = vhost.NewTcpHttpTunnelMuxer(l, DefaultTunnelTimeout) ```