A Note on VoiceXML Documents, Applications and Grammar Scopes

(The picture above was taken from W3C VoiceXML 2.0 CR specification document)

• multiple VoiceXML documents can form a logical application by specifying the application root document as an attribute of the <vxml> element
• the root document remains loaded as long as there is a leaf document referring to it
• ECMAScript scopes of the root document are available to all leaf documents
• we distinguish four grammar scopes in VoiceXML:
  1. slot-level (field)
  2. form-level (form-wide, active only when the form is being visited
  3. document-level (form-wide, active throughout the document
  4. application-level (document-level grammars in the application root)