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I think the only way to solve this is to manually (and gradually) add required properties to our schema models in lib-auto-generated, and ensure the required designation is included in the translated OpenAPI definition.
This may be more challenging to solve for types used in both requests and responses where certain fields may not be provided in requests to create a resource, but may always be required/provided in other contexts (e.g. object IDs generated by the system).
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