When keeping tabs on your ZF applications, it's often difficult to separate application errors from general PHP errors, and if you aggregate them in the same location as your web server errors, this can become more difficult still.

Additionally, PHP's error reporting doesn't provide a ton of context, even when reporting uncaught exceptions — typically you'll only get a cryptic exception message, and what file and line emitted it.

Zend Server's Monitor extension has some capabilities for providing more context, and does much of this by default: request and environment settings available when the error was logged, the function name and arguments provided, and a full backtrace are available for you to inspect. Additionally, the Monitor extension includes an API that allows you to trigger custom Monitor events, and you can provide additional context when doing so — such as passing objects or arrays that may help provide context when debugging.