For AI agents: a documentation index is available at the root level at /llms.txt and /llms-full.txt. Append /llms.txt to any URL for a page-level index, or .md for the markdown version of any page.
Book a demoLog inStart for free
  • Overview
    • Introduction
    • How it works
    • Quickstart
    • Customer showcase
  • Working with SDKs
    • Project structure
    • Adding custom code
    • Migrating to Replay
    • Capabilities
  • Generators
      • Generating an SDK
      • Publishing to PyPI
      • Configuration
      • Adding custom code
      • Dynamic authentication
      • aiohttp support
      • Changelog
      • Customer showcase
  • Reference
    • generators.yml
Checking status...
SOC2Soc 2 Type II
© 2026 Fern • Birch Solutions, Inc., a Postman company

Documentation

SDKsDocsAsk FernCLI Reference

API Definitions

OpenAPIAsyncAPIOpenRPCgRPC

Resources

BlogSupportPricing

Company

Brand KitPrivacy PolicyTerms of Service
LogoLogo
Book a demoLog inStart for free
GeneratorsPython

Changelog

April 15, 2026
April 15, 2026

5.4.0-rc.1

(fix): Fix auth: any with OAuth + header auth schemes (e.g. API key):

  • Header auth parameters are now included in the generated client constructor (previously silently dropped when OAuth was present)
  • Header auth parameters are passed through to the client wrapper (previously missing, causing a runtime TypeError)
  • Header auth types are made optional when alongside OAuth, with conditional header setting
  • The client can now be instantiated with just a header auth credential (e.g. api_key) without requiring OAuth credentials or a bearer token
Was this page helpful?
Edit this page
Previous

April 16, 2026

Next

April 14, 2026