Fern SDKs

Use this skill when a task involves generating or publishing SDKs with Fern: editing fern/generators.yml or fern/fern.config.json, adding a language, changing where an SDK is published, keeping hand-written code across regenerations, or debugging a fern generate run. For editing the API spec itself (OpenAPI, x-fern-* extensions, overlays) use the fern-spec skill; for CI workflows use fern-workflows; for docs sites use fern-docs.

Fern resources

Look things up instead of guessing. Fern options are strict: an unknown key in generators.yml or a generator's config fails validation.

• Docs: https://buildwithfern.com/learn/sdks — append .md to any docs URL to get Markdown (for example https://buildwithfern.com/learn/sdks/reference/generators-yml-reference.md).
• generators.yml reference: https://buildwithfern.com/learn/sdks/reference/generators-yml-reference
• Per-language pages (configuration, publishing, custom code): https://buildwithfern.com/learn/sdks/generators/<typescript|python|java|go|csharp|php|ruby|swift|rust>/...
• CLI reference: https://buildwithfern.com/learn/cli-api-reference/cli-reference/sdk-commands
• llms.txt: https://buildwithfern.com/learn/llms.txt
• Fern MCP server (if the agent supports MCP): claude mcp add --transport http fern https://buildwithfern.com/learn/_mcp/server
• Schema for editor validation: add # yaml-language-server: $schema=https://schema.buildwithfern.dev/generators-yml.json to the top of generators.yml.

Routing

Load only the reference you need.