🌿 Fern Scribe: Add a comprehensive list of all extension headers...

fern/products/openapi-def/openapi-def.yml

@@ -4,7 +4,7 @@ navigation:
   - page: Authentication
     path: ./pages/auth.mdx
   - page: Servers
-    path: ./pages/servers.mdx            
+    path: ./pages/servers.mdx
   - section: Endpoints
     slug: endpoints
     contents:
@@ -17,6 +17,9 @@ navigation:
       - page: Server-Sent Events
         path: ./pages/endpoints/sse.mdx
         slug: sse
+      - page: others
+        title: Other
+        path: ./pages/extensions/others.mdx
   - section: Extensions
     slug: extensions
     contents:
@@ -38,7 +41,7 @@ navigation:
       - page: Overlay Customizations
         path: ./pages/overrides.mdx
       - page: Sync your OpenAPI Specification
-        path: ./pages/automation.mdx            
+        path: ./pages/automation.mdx
   - section: Integrate your Server Framework
     slug: frameworks
     contents:

fern/products/openapi-definition/pages/extensions/others.mdx

@@ -0,0 +1,91 @@
+# OpenAPI Extension Headers
+
+The following extension headers are supported in Fern's OpenAPI implementation:
+
+## x-fern-sdk-variables
+
+Allows defining reusable variables that can be referenced across SDK operations. Variables defined here will be available as client constructor parameters.
+
+```yaml
+x-fern-sdk-variables:
+  project_id:
+    type: string 
+    description: "The project ID"
+    pattern: "^proj_[a-zA-Z0-9]+$"
+```
+
+Variables can then be referenced in path parameters using `x-fern-sdk-variable`:
+
+```yaml
+paths:
+  /v1/projects/{project_id}/users:
+    parameters:
+      - name: project_id
+        in: path
+        required: true
+        schema:
+          type: string
+        x-fern-sdk-variable: project_id
+```
+
+This allows SDK users to provide the variable once during client initialization rather than for each API call.
+
+## x-fern-sdk-group-name
+
+Groups related operations together in the generated SDK. Operations with the same group name will be organized under a common namespace/class.
+
+```yaml
+paths:
+  /users:
+    get:
+      x-fern-sdk-group-name: users
+```
+
+## x-fern-sdk-method-name
+
+Customizes the method name for an operation in the generated SDK.
+
+```yaml
+paths:
+  /users:
+    get:
+      x-fern-sdk-method-name: list
+```
+
+## x-fern-ignore
+
+Excludes an operation from the generated SDK when set to `true`.
+
+```yaml
+paths:
+  /internal/metrics:
+    get:
+      x-fern-ignore: true
+```
+
+## x-fern-pagination
+
+Configures pagination behavior for list operations. Requires specifying cursor and results fields.
+
+```yaml
+paths:
+  /users:
+    get:
+      x-fern-pagination:
+        cursor: "$request.after"
+        next_cursor: "$response.page_info.end_cursor"
+        results: "$response.data"
+```
+
+## x-fern-sdk-return-value
+
+Specifies which part of the response should be returned from SDK methods.
+
+```yaml
+paths:
+  /users/{id}:
+    get:
+      x-fern-sdk-return-value: data
+```
+
+For complete OpenAPI examples using these extensions, see the [OpenAPI Quick Start guide](/openapi-definition/quickstart).

fern/products/sdks/overview/python/configuration.mdx

@@ -21,13 +21,15 @@ groups:
 ## SDK Configuration Options
 
 <ParamField path="additional_init_exports" type="array" default="null" required={false} toc={true}>
+  Additional items to export in the package's __init__.py file.
 </ParamField>
 
 <ParamField path="default_bytes_stream_chunk_size" type="number" default="null" required={false} toc={true}>
   The chunk size to use (if any) when processing a response bytes stream within `iter_bytes` or `aiter_bytes` results in: `for chunk in response.iter_bytes(chunk_size=<default_bytes_stream_chunk_size>):`
 </ParamField>
 
 <ParamField path="exclude_types_from_init_exports" type="bool" default="false" required={false} toc={true}>
+  When enabled, types will not be exported in the package's __init__.py file.
 </ParamField>
 
 <ParamField path="extra_dependencies" type="object" default="{}" required={false} toc={true}>
@@ -40,27 +42,31 @@ groups:
 </ParamField>
 
 <ParamField path="extra_dev_dependencies" type="object" default="{}" required={false} toc={true}>
+  Additional development dependencies to include in the generated package.
 </ParamField>
 
 <ParamField path="extras" type="object" default="{}" required={false} toc={true}>
+  Optional package extras/features to include in setup.py.
 </ParamField>
 
 <ParamField path="flat_layout" type="bool" default="false" required={false} toc={true}>
+  When enabled, generates a flatter package structure without nested directories.
 </ParamField>
 
 <ParamField path="follow_redirects_by_default" type="bool" default="true" required={false} toc={true}>
   Whether to follow redirects by default in HTTP requests.
 </ParamField>
 
 <ParamField path="improved_imports" type="bool" default="true" required={false} toc={true}>
-  Feature flag that improves imports in the Python SDK by removing nested `resources` directory
+  Feature flag that improves imports in the Python SDK by removing nested `resources` directory.
 </ParamField>
 
 <ParamField path="include_legacy_wire_tests" type="bool" default="false" required={false} toc={true}>
-  Whether or not to include legacy wire tests in the generated SDK
+  Whether or not to include legacy wire tests in the generated SDK.
 </ParamField>
 
 <ParamField path="include_union_utils" type="bool" default="false" required={false} toc={true}>
+  When enabled, generates additional utilities for union types.
 </ParamField>
 
 <ParamField path="inline_path_params" type="bool" default="false" required={false} toc={true}>
@@ -72,12 +78,9 @@ groups:
 </ParamField>
 
 <ParamField path="package_name" type="string" default="null" required={false} toc={true}>
-
-Specifies the Python package name that users will import your generated client
-from.
+  Specifies the Python package name that users will import your generated client from.
 
-For example, setting `package_name: "my_custom_package"` enables users to use
-`my_custom_package import Client` to import your client:
+  For example, setting `package_name: "my_custom_package"` enables users to use `from my_custom_package import Client` to import your client:
 
 ```yaml {7-10}
 default-group: local
@@ -92,6 +95,7 @@ groups:
 </ParamField>
 
 <ParamField path="pydantic_config" type="SdkPydanticModelCustomConfig" default="SdkPydanticModelCustomConfig()" required={false} toc={true}>
+  Configuration options for Pydantic model generation.
 </ParamField>
 
 <ParamField path="pydantic_config.include_union_utils" type="bool" default="false" required={false} toc={true}>
@@ -112,12 +116,10 @@ groups:
   # Visit every case in the union
   shape = get_shape()
   shape.visit(
-    circle: lambda circle: do_something_with_circle(circle),
-    triangle: lambda triangle: do_something_with_triangle(triangle),
+    circle=lambda circle: do_something_with_circle(circle),
+    triangle=lambda triangle: do_something_with_triangle(triangle),
   )
   ```
-
-  When enabled, the python generator will not run Black formatting in the generated code. Black is slow so this can potentially speed up code generation quite a bit.
 </ParamField>
 
 <ParamField path="pydantic_config.version" type="'v1' | 'v2' | 'both' | 'v1_on_v2'" default="both" required={false} toc={true}>
@@ -140,20 +142,39 @@ groups:
 </ParamField>
 
 <ParamField path="pyproject_toml" type="string" default="null" required={false} toc={true}>
+  Custom pyproject.toml content to include in the generated package.
+</ParamField>
+
+<ParamField path="sdk_variables" type="object" default="{}" required={false} toc={true}>
+  Variables that can be set once when instantiating the client and used across multiple requests. For OpenAPI specs, these are defined using the `x-fern-sdk-variables` extension. Example:
+
+  ```yaml
+  x-fern-sdk-variables:
+    project_id:
+      type: string
+      description: The project ID to use for all requests
+  ```
+
+  This allows setting the variable once when creating the client:
+  ```python
+  client = Client(project_id="proj_123")
+  ```
 </ParamField>
 
 <ParamField path="should_generate_websocket_clients" type="bool" default="false" required={false} toc={true}>
   Feature flag that enables generation of Python websocket clients.
 </ParamField>
 
 <ParamField path="skip_formatting" type="bool" default="false" required={false} toc={true}>
+  When true, skips code formatting of the generated SDK.
 </ParamField>
 
 <ParamField path="timeout_in_seconds" type="number | 'infinity'" default="60" required={false} toc={true}>
   By default, the generator generates a client that times out after 60 seconds. You can customize this value by providing a different number or setting to `infinity` to get rid of timeouts.
 </ParamField>
 
 <ParamField path="use_api_name_in_package" type="bool" default="false" required={false} toc={true}>
+  When true, includes the API name in the generated package name.
 </ParamField>
 
 <ParamField path="use_inheritance_for_extended_models" type="bool" default="true" required={false} toc={true}>