HTML Batch validations

Hi 
 
I am developing a tool for validating the quality of web files. This
tool will be part of the sonar quality dashboard, a popular open source
product used by developers in java, .NET and PHP. See [1] and [2]. 
 
The goal is to help developers aiming to deliver standards compliant web
sites. We do that by inspecting and validating the HTML, as part of the
continuous integration process. The sonar dashboard provides a
convenient tool to inpects the errors, and browse to the HTML. On top of
that, metrics are provided and can be followed over time. 

The W3C Markup validator is a powerful and important tool for validating
HTML. Therefore I am planning to provide a batch interface to this
service. I have already run some tests with the W3C Markup validator
with success.  

I am aware that using the W3C Markup Validator in a batch process may
degrade performance for other users. I have implemented a 1 second delay
between the requests, as suggested on the W3C web site. But what if
multiple users would start a batch validation? My tool will make this
easy... I recommend users of my tool to install their own Markup
Validation service, but I would not be able to stop them from using
http://validator.w3.org/. What are your thoughts on this topic?

Do you have other concerns and suggestions? 

Let me know if you need more information. 

Kind regards 

Matthijs Galesloot 

[1] http://www.sonarsource.org/ 
[2] http://docs.codehaus.org/display/SONAR/Web+Plugin