gistfile1.aw

<?php

class TestController implements Controller
{
    /**
     * @validate id numeric
     * @validate message maxlen(300)
     * @method post
     * @ajax false
     */
    public function messageAction($id, $message)
    {
        // will only be called when both $id and $message are available and have passed the validation
    }
}

interface Validator
{
    public function validate($value, array $args);
}

public NumericValidator implements Validator
{
    public function validate($value, array $args)
    {
        return is_numeric($value);
    }
}