Drop an OpenAPI spec
We turn its operations into tools and deploy a hosted MCP server.
Drop or click to upload
yaml, yml, or json
If a URL and pasted spec are present, the URL wins.
Don’t have a spec?
Advanced options
Paste one generator config object or a generators.yml with one config block.
Deploying your server…
Keep this page open while Fern compiles and publishes your tools.
Your server is live!
Your MCP server is live at
Advanced setup
These controls also live in the server admin.
Shared server-side credential
Set or rotate a deployer credential. It is encrypted server-side and shared by all callers, so callers do not need it. This public demo control is only available for demo-owned deployments.
Encode an API key (client-held credential)
Your key is sent once to be sealed, is never stored, and the returned token is bound to this server and its expiry. Unlike the shared server-side secret, only clients holding this token use the key.
Connect with your own OAuth app
Connecting clients are prompted through OAuth automatically; do not paste an access token into an MCP header.
Register this redirect URI in your app:
Your secret goes into a sealed HttpOnly 10-minute cookie and never appears in a URL.
OAuth owner configuration
Connecting clients are prompted through OAuth automatically; do not paste an access token into an MCP header.
Configure the deployer's shared OAuth app. This is separate from users bringing their own app above.
Register this redirect URI upstream:
Test tools
For schema-driven inputs, responses, and call history, open the server page tool tester.
Client credentials
Configure an app-level token shared by all callers. This flow has no user login.
Try it with an agent
Ask a question. The assistant can call this server’s MCP tools through Workers AI.
Authentication
Credentials are sent only with chat requests and are never stored. You can also tell the agent a key in chat; that value necessarily enters the model context.
This deployment uses MCP OAuth. Connect via OAuth instead of pasting an Authorization token.