InvocationContext not persisting contents

Jan 29, 2015 at 10:57 PM
(Moved from MSDN Forum as suggested.)

I am added a value to the InvocationContext dictionary, however it doesn't persist to the next call. i.e. each call in the chain that's intercepted is returning false for InvocationContext.ContainsKey("tracing-id").
public IMethodReturn Invoke(IMethodInvocation input, GetNextInterceptionBehaviorDelegate getNext)    
     Guid tracingId;        
     if (!input.InvocationContext.ContainsKey(TRACING_ID))        
        tracingId = _tracingIdProvider.NewTracingId();  
        input.InvocationContext.Add(TRACING_ID, tracingId);
         tracingId = (Guid)input.InvocationContext[TRACING_ID];
      var methodReturn = getNext()(input, getNext);
      return methodReturn;    
I can add an entry to the InvocationContext, however, when getNext()(input, getNext) is invoked and the next call is intercepted the InvocationContext is empty.

Am I misunderstanding how InvocationContext is used? If so, what's the correct way to persist something like an ID from one method call to the next?