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Changelog

June 1, 2026
June 1, 2026

1.13.1

(fix): Generated model classes now include fields inherited from parent types (Fern extends / OpenAPI allOf). Previously, derived models — including discriminated union variants — only carried their own declared properties and silently dropped fields contributed by their parents, leaving deserialized responses without id, name, and other inherited common fields.

1.13.0

(feat): Add a max_retries: keyword argument to the generated root Client constructor. Consumers can now configure the default retry count once at client construction (e.g. Client.new(max_retries: 5)) instead of relying on the generation-time maxRetries setting in generators.yml. The constructor default still respects the configured value (or 2 when unset), so existing behavior is preserved.

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May 15, 2026