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        • Global headers
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  • Global
  • Endpoint
  • Combining global and endpoint-level settings
OpenAPIExtensions

API Explorer control

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Global headers

The API Explorer is enabled by default for all endpoints. Use x-fern-explorer to disable or it globally or to override it per operation. This is commonly used to disable the Explorer for destructive operations, payment processing, or admin-only endpoints.

Global

To disable the API Explorer for your entire API, add x-fern-explorer at the root level:

openapi.yml
1openapi: 3.0.2
2x-fern-explorer: false # Disable Explorer for all endpoints
3info:
4 title: My API
5 version: 1.0.0
6paths:
7 /payments:
8 get:
9 operationId: list_payments

Endpoint

To control the API Explorer for individual endpoints, use x-fern-explorer:

openapi.yml
1paths:
2 /payments:
3 get:
4 x-fern-explorer: true # Enable Explorer for safe read operation
5 /payments/charge:
6 post:
7 x-fern-explorer: false # Disable to prevent accidental transactions

Combining global and endpoint-level settings

You can combine both extensions to set a default behavior globally and override it for specific endpoints:

openapi.yml
1openapi: 3.0.2
2x-fern-explorer: false # Disable Explorer globally
3info:
4 title: My API
5 version: 1.0.0
6paths:
7 /payments:
8 get:
9 operationId: list_payments
10 x-fern-explorer: true # Enable Explorer for safe read operation
11 /payments/charge:
12 post:
13 operationId: charge_payment
14 # Remains disabled (global setting applies)