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  • Changelog
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CLI reference

Changelog

June 24

5.50.6

(fix): Forward edit-this-page GitHub config (owner/repo/branch/host) from docs.yml into the ledger manifest so the docs reader can synthesize the correct "Edit this page" URL without depending on…

June 23

5.50.5

(fix): fern check no longer reports valid examples as invalid when a schema uses patternProperties (OpenAPI 3.1 / JSON Schema). When a schema declares patternProperties, example keys are no longer…

June 22

5.50.4

(fix): Fixed the local C# dynamic-snippet test runner so it strips the docs-only exported-client-class-name override before generating snippet tests. The compiled snippets now reference the generated…

June 19

5.50.3

(fix): Fixes translated locales in ledger publishing mode (currently opt-in).

June 18

5.50.2

(fix): Add retry with exponential backoff to registerApiDefinition during docs publish. Large docs sites (e.g. 30+ API versions) could hit transient connection aborts from FDR; the CLI now retries up…

5.50.1

(chore): Bump js-yaml to 4.2.0 across all transitive dependencies to fix CVE-2026-53550 (quadratic-complexity DoS in merge key handling).

June 17

5.50.0

(feat): Add docs deployment ledger. Set FERN_DOCS_DEPLOY_MODE=ledger to publish via the new ledger backend; legacy (default) uses the existing register flow. The ledger path uses content-addressed…

5.49.3

(fix): When a generator breaks an import cycle by relocating types into a shared package, the local generation runner now applies those relocations to the IR that powers host-side dynamic snippet…

June 16

5.49.2

(fix): infer-discriminated-union-base-properties now lifts properties that every variant inherits via a shared allOf $ref parent. Previously these were dropped to protect TypeScript's _Base from…

June 15

5.49.1

(fix): Library docs generator now writes module overview pages as index.mdx inside their directory (e.g. adapters/index.mdx) instead of as sibling files (adapters.mdx), eliminating duplicate entries…

June 13

5.49.0

(feat): Add support for x-fern-subtitle OpenAPI extension on endpoints. When set, the subtitle is rendered below the endpoint title in the docs UI.

5.48.0

(feat): Add a --local flag to fern docs md generate that runs the library documentation parsers locally in Docker instead of using Fern's servers. Local generation requires no authentication and…

June 12

5.47.6

(fix): Fix frontmatter values with leading zeros being corrupted during docs publish. grayMatter.stringify() in parseImagePaths would strip quotes from values like '001999' (non-octal digits),…

5.47.5

(fix): Fix v3 OpenAPI importer dropping types that are only referenced through a list/map of a $ref when audience filtering is enabled. Array and map aliases now record the referenced named type in…

5.47.4

(fix): Group GraphQL queries by parent field in the sidebar; mutations and subscriptions remain flat. Field path is now included on all GraphQL operations for correct snippet nesting. (fix): Include…

5.47.3

(fix): Use string literal for this.name in error classes instead of this.constructor.name, which gets mangled by minifiers. (fix): Fix text/* content types (e.g. text/csv, text/xml) being silently…

5.47.2

(fix): Stop dropping custom scalars in the GraphQL converter. Custom scalars (e.g. DateTime, URL, EmailAddress) are now emitted as named alias types in the types map with a stable id, and references…

June 11

5.47.1

(fix): Fix v3 OpenAPI importer producing empty discriminated unions when discriminator.propertyName is present but discriminator.mapping is absent. The importer now infers the mapping from…

5.47.0

(feat): Add page-actions.options.skills to docs.yml to enable and configure the "Install skills" page action on docs sites. Presence of the key enables the action (an empty object enables it with all…

5.46.1

(fix): Bump bundled @fern-api/replay (via generator-cli 0.9.38) to 0.18.0: replay detection filters .fernignore-protected files before materializing patches, handles trailing-slash patterns like…

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