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
    • What is an API definition?
    • Project structure
      • Overview
      • Overrides
      • Authentication
      • Servers
      • Sync your specification
        • Overview
        • Audiences
        • Availability
        • Request + response examples
        • Ignoring elements
        • Server names
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
AsyncAPIExtensions

Server names

||View as Markdown|
Was this page helpful?
Edit this page
Previous

Ignoring operations, channels, or schemas

Next

What is an OpenRPC specification?

Specify custom names for servers:

asyncapi.yml
1servers:
2  production:
3    host: api.yourcompany.com
4    x-fern-server-name: Production
5    protocol: wss
6  staging:
7    host: staging.api.yourcompany.com
8    x-fern-server-name: Staging
9    protocol: wss