How to diagnose WCF Request errors if I don't have a "<behaviors>" node in my Web.Config?

Question

Seeing the dreaded Request Error page while testing your WCF Web Service?

Well, worry not, because this StackOverflow answer shows you how to turn on detailed error display: WCF Data Service - How To Diagnose Request Error?

But ... hang on, we don't have a Web.Config that looks anything like that one.

Ours just has a system.serviceModel and that's it.

<system.serviceModel>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true"></serviceHostingEnvironment>
    <standardEndpoints>
        <webHttpEndpoint>
            <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="true"></standardEndpoint>
        </webHttpEndpoint>
    </standardEndpoints>
</system.serviceModel>

If we go for it and simply add the following:

<behaviors>
    <serviceBehaviors>
        <behavior name="DataServiceBehavior">
            <serviceDebug includeExceptionDetailInFaults="true"/>
        </behavior>
    </serviceBehaviors>
</behaviors>

on to the end, then boy is it unhappy:

Update/Edit

Based on answers and comments from @burning_LEGION and @Chris (see below) I now have a Web.Config which looks like this:

  <system.serviceModel>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true"></serviceHostingEnvironment>
      <standardEndpoints>
    <webHttpEndpoint>
          <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="true" behaviorConfiguration="DataServiceBehavior"></standardEndpoint>
    </webHttpEndpoint>
      </standardEndpoints>

      <behaviors>
    <serviceBehaviors>
      <behavior name="DataServiceBehavior">
        <serviceDebug includeExceptionDetailInFaults="true"/>
      </behavior>
    </serviceBehaviors>
      </behaviors>
  </system.serviceModel>

But I'm getting a Server Error:

Parser Error Message: Unrecognized attribute 'behaviorConfiguration'. Note that attribute names are case-sensitive.

Answer 1

Thanks to Chris and burning_Legion for pointing the way. This was the system.serviceModel which I eventually ended up with and which successfully shows the error detail.

It's per @burning_LEGION's answer but without the name attribute on the behavior:

  <system.serviceModel>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true"></serviceHostingEnvironment>
      <standardEndpoints>
    <webHttpEndpoint>
          <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="true"></standardEndpoint>
    </webHttpEndpoint>
      </standardEndpoints>

    <behaviors>
      <serviceBehaviors>
        <behavior>
          <serviceMetadata httpGetEnabled="true"/>
          <serviceDebug includeExceptionDetailInFaults="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>

  </system.serviceModel>

Answer 2

behaviors must be in tag system.serviceModel

<system.serviceModel>
    <serviceHostingEnvironment aspNetCompatibilityEnabled="true"></serviceHostingEnvironment>
    <standardEndpoints>
        <webHttpEndpoint>
            <standardEndpoint name="" helpEnabled="true" automaticFormatSelectionEnabled="true"></standardEndpoint>
        </webHttpEndpoint>
    </standardEndpoints>   
    <behaviors>
       <serviceBehaviors>
           <behavior name="DataServiceBehavior">
              <serviceDebug includeExceptionDetailInFaults="true"/>
           </behavior>
       </serviceBehaviors>
    </behaviors> 
</system.serviceModel>