Update README.md

Author: tom-tan

README.md

@@ -1,2 +1,45 @@
 # cwl-upload-conformance-badges
-Action for uploading CWL conformance badges
+It is a custom Github Action for uploading CWL conformance badges to specified repository.
+
+## Example
+
+```yaml
+jobs:
+  conformance:
+    runs-on: ubuntu-latest
+    steps:
+      ...
+
+      - name: Run conformance tests
+        id: run-conformance
+        uses: tom-tan/[email protected]
+        with:
+          cwlVersion: v1.0
+          runner: your-runner
+          timeout: 30
+          skip-python-install: true
+
+      - name: Save badges
+        if: success() && github.event_name == 'push' # upload badges when this action is invoked by `push` event
+        uses: tom-tan/[email protected]
+        with:
+          cwlVersion: v1.0
+          runner-name: your-runner
+          badgedir: ${{ steps.run-conformance.outputs.badgedir }}
+          repository: ${{ github.repository_owner }}/conformance
+          upload-default-branch: true
+          token: ${{ secrets.CONFORMANCE_TOKEN }}
+```
+
+## Input parameters
+
+| Parameters | Required | Default | Description |
+|---|---|---|---|
+| `cwlVersion` | true | - | target CWL version |
+| `runne-namer` | true | - | name of CWL runner |
+| `badgedir` | true | - | full path to the directory that stores conformance badges |
+| `repository` | true | - | repository (in the form of `owner/repo`) to store badges |
+| `upload-default-branch` | false | false | whether uploading the result of HEAD in the default branch |
+| `token` | true | - | token to commit the repository specified in the `repository` field |
+
+This action has no output parameters.