To mitigate the risk of Field Duplication attacks, you can take the following steps:

- **Implement Query Complexity Limits:** Enforce query complexity rules that consider duplicated fields as part of the overall cost of a query. This helps in limiting the number of duplicate fields processed, thus protecting the server from resource exhaustion.
- **Limit Field Repetitions:** Configure server-side limits on the number of times a field can be duplicated in a single GraphQL query. You can use tools like GraphQL Armor to enforce such limits and prevent field duplication overloading.

=== "JavaScript"
  ```JavaScript
   // Configuring for GraphQL Armor
   GraphQLArmorConfig({
           maxFieldDuplicates: {
      // Enable or disable the plugin | default: true
               enabled: true,

      // Set the maximum number of field duplications allowed per query | default: 10
               n: 10,

      // Callbacks to execute when a query is accepted
               onAccept: [],

      // Callbacks to execute when a query is rejected
               onReject: [],

      // Propagate rejection details to the client | default: true
               propagateOnRejection: true,
                   }
               })
  ```

=== "Python"
  ```Python
   import graphql
   from graphql.language import ast
   from graphql.language import parser
   from settings import api
   def validate_field_duplicates(query: str) -> None:
       """
           This validation prevents the execution of queries containing excessive
           duplicated fields to avoid overloading the server.
           """
           class FieldDuplicationParser(parser.Parser):
               def parse_duplicates(self) -> list[ast.FieldNode]:
                       field_counts = {}
                           while self.peek(graphql.TokenKind.NAME):
                               field_name = self.parse_field().name.value
                                   field_counts[field_name] = field_counts.get(field_name, 0) + 1
                                   if field_counts[field_name] > api.API_MAX_FIELD_DUPLICATES:
                                       raise graphql.GraphQLError("Exception - Max field duplicates exceeded")
                                   return []
                   ast_parser = FieldDuplicationParser(query)
           ast_parser.parse_document()
  ```