Changelog

4.35.0

(feat): Add --id flag to fern generate --docs --preview for stable preview URLs. When --id <name> is provided, the preview domain uses the given identifier instead of a random UUID, so subsequent runs with the same ID overwrite the previous preview and the URL stays constant. In non-CI environments the CLI checks whether the preview already exists and prompts for confirmation before overwriting (skip with --force).

4.34.0

(feat): Add infer-default-environment API definition setting. When set to false, the OpenAPI importer will not automatically designate the first server as the default environment, requiring SDK users to explicitly provide a base URL. Defaults to true to preserve existing behavior.

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api:
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  specs:
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    - openapi: ./openapi.yml
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      settings:
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        infer-default-environment: false

4.33.0

(feat): Add enums-coerceable-to-literals option for coerce-consts-to, and make it the new default. This behaves like enums (const values become single-element enums) but allows coerce-enums-to-literals to transitively coerce them to literals, which is consistent with past default behavior. The existing enums option continues to block this transitive coercion.

4.32.2

(fix): Fix custom LICENSE files not being included in SDK output when using fern generate --local. The license path (e.g. ../../LICENSE) was resolved relative to fern.config.json instead of generators.yml, causing the file to not be found in multi-API workspace layouts where these files are in different directories.

4.32.1

(fix): Downgrade the no-openapi-v2-in-docs validation rule from an error to a warning. Fern supports OpenAPI 2.0 (Swagger) specs in docs generation, so fern check no longer fails when Swagger 2.0 specs are present.

4.32.0

(feat): Add support for the x-fern-sdk-method-name extension on AsyncAPI v2 publish and subscribe operations. Users can now customize the generated SDK method name (e.g., changing sendPublish to send) without migrating to AsyncAPI v3.

4.31.3

(fix): Enable WebSocket auth in AsyncAPI by populating IR auth schemes. The AsyncAPI converter now converts security schemes from both generators.yml auth overrides and native AsyncAPI spec securitySchemes into IR AuthScheme objects, so the docs explorer correctly renders auth forms for WebSocket endpoints.

4.31.1

(fix): Fix x-fern-streaming with stream-condition emitting the condition field as an optional boolean instead of a required literal in split request types. When the source property was nullable (type: [boolean, "null"]), the spread order allowed the original property to overwrite the literal overrides.