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GraphQL SDL service definition allows you to enter the location of a GraphQL SDL to which to constrain the responder and, optionally, restrict the response to only those fields specified in the Selection Set of the request. For details on configuring Message Responders that are constrained to a GraphQL SDL, see Definition Tab. You can define custom scalars used in your SDL in the preferences (go to Parasoft > Preferences > GraphQL). See Additional Preference Settings#GraphQL for more information.
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