How to format documentation in MS_Description extendedproperties?

I'm using a 'MS_Description' extended property to document parameters in a stored procedure. This parameter's documentation requires more structure than just plain text. That is I would like to describe: "if value = x, then action A is taken; if value = y, then action B is taken, ...".

What is the best way to store this structure?

The following approaches occured to me:

• 
  

  Use html within the 'MS_Description', e.g.

  
  

  
  EXEC sp_addextendedproperty
      @name = N'MS_Description',
      @value = N'
          Selects the foobar.  Can have the following values: 
          <dl>
               <dt>x</dt><dd>does A</dd> 
               <dt>y</dt><dd>does B</dd></dl>'
      @level0type = N'SCHEMA',      @level0name = [dbo],
      @level1type = N'PROCEDURE',   @level1name = N'SE_DemoProc'
      @level2type = N'PARAMETER',   @level2name = N'DemoPar';
  
  

  
  
  
  
  • Would developpers DBAs automatically parse html in their heads?
  
  
  
  


• 
  

  Use visual studio xml document tags the extendedproperty, @value would become:

  
  

  
  @value = N'
          Selects the foobar.  Can have the following values: 
          <list type="bullet">
               <item><term>x</term><description>does A</description></item>
               <item><term>y</term><description>does B</description></item>
          </list>'
  
  

  
  
  
  
  • 
    

    Does SSMS, visual studio, and/or other tools interpret Xml document tags in MS_Description extended properties?

    
    
  
  
  • 
    

    Does extra semantics of '', '', and '' improve people's understanding more than the html?

    
    
  
  
  
  


• 
  

  Use a different extended property to document the values that a parameter excepts?

  
  
  
  
  • Which property is commonly used for this?
  
  
  • 
    

    How to encode these multiple values?

    
    

    As far as I know, an extended property can only occur once for a given (schema, procedure, parameter)-combination.

    
    
  
  
  
  


• 
  

  Using newlines, tabs, and '*' to format the plain text will not work since whitespace is collapsed from sql scripts.

  
  
  
  
  • does escaping newlines and tabs work?
  
  
  
  


• 
  

  Perhaps, I should avoid the mode parameter altogether and split this stored procedure into several distinct precedures. (But that would be a different question and out of scope for this one.)