add info about origin field

Author: devalog

README.md

@@ -1,15 +1,15 @@
 # sync-openapi
 
-A GitHub Action to sync OpenAPI specifications with your Fern setup. Choose your scenario:
+A GitHub Action to [sync OpenAPI specifications with your Fern setup](/learn/api-definitions/openapi/sync-your-open-api-specification). Choose your scenario:
 
-- **Case 1: Sync from public URL (most common).** Your OpenAPI spec is hosted at a publicly available URL and you want to pull it into your fern folder
-- **Case 2: Sync between repositories**: Your OpenAPI spec lives in one repository and you want to sync it to another repository where your fern folder lives (like fern-config)
+- **Case 1: Sync from public URL (most common).** Your OpenAPI spec is hosted at a publicly available URL and you want to pull it into your fern folder. The GitHub Action uses `fern api update` to pull the latest version of your OpenAPI spec from the `origin` field in your `generators.yml` file. 
+- **Case 2: Sync between repositories**: Your OpenAPI spec lives in one repository and you want to sync it to another repository where your fern folder lives (like fern-config). The GitHub Action uses explicit file mappings to pull the latest version of your OpenAPI spec. 
 
 ## Usage
 
-### Case 1: Sync specs using `fern api update` (recommended)
+### Case 1: Sync specs from public URL (recommended)
 
-1. In your your source repo, create a file named `sync-openapi.yml` in `.github/workflows/`. 
+1. In your source repo, create a file named `sync-openapi.yml` in `.github/workflows/`. 
 2. Include the following contents in `sync-openapi.yml`: 
 
 ```yaml
@@ -42,7 +42,7 @@ jobs:
 
 ### Case 2: Sync files/folders between repositories
 
-1. In your your source repo, create a file named `sync-openapi.yml` in `.github/workflows/`. 
+1. In your source repo, create a file named `sync-openapi.yml` in `.github/workflows/`. 
 2. Include the following contents in `sync-openapi.yml`: 
 
 ```yaml
@@ -88,9 +88,9 @@ jobs:
 | `branch`            | Branch to push to in the target repository                                                                                                 | Yes      | -                         | 1, 2   |
 | `auto_merge`        | If `true`, pushes directly to the branch; if `false`, creates a PR from the branch onto `main`                                            | No       | `false`                   | 1, 2   |
 | `add_timestamp`     | If `true`, appends a timestamp to the branch name                                                                                          | No       | `true`                    | 1, 2   |
-| `sources`           | Array of mappings with `from`, `to`, and optional `exclude` fields                                                                         | Yes      | -                         | 1   |
-| `repository`        | Target repository in format `org/repo`                                                                                                     | Yes      | -                         | 1   |
-| `update_from_source`| If `true`, syncs from the source spec files rather than using existing intermediate formats                                               | No       | `false`                   | 2   |
+| `sources`           | Array of mappings with `from`, `to`, and optional `exclude` fields                                                                         | Yes      | -                         | 2   |
+| `repository`        | Target repository in format `org/repo`                                                                                                     | Yes      | -                         | 2   |
+| `update_from_source`| If `true`, syncs from the source spec files rather than using existing intermediate formats                                               | No       | `false`                   | 1   |
 
 
 **Note: you must set `auto_merge: true` when using `branch: main`**