A GraphQL code generation tool can inspect a schema and generate TypeScript representations of scalar types, object types, enums, input types, interfaces, unions, and resolver signatures.

For example, a GraphQL User type can become a TypeScript type. A GraphQL UserInput can become an input type, while resolver type definitions can describe the expected arguments, parent values, context, and return values.

This reduces repetitive type declarations and makes schema changes visible to the TypeScript compiler.