diff --git a/README.md b/README.md
new file mode 100644
index 0000000..5f374a0
--- /dev/null
+++ b/README.md
@@ -0,0 +1,17 @@
+# reviewdog caching action
+
+This action loads `reviewdog` into the GitHub Action tools-cache.
+
+## Inputs
+
+### `version`
+
+**Required** The version of reviewdog to load. Default `"latest"`.
+
+## Example usage
+
+```yaml
+uses: oknowrun/action-reviewdog@v1
+with:
+  version: 0.10.0
+```
diff --git a/index.js b/index.js
index 9a47d3a..f25160c 100644
--- a/index.js
+++ b/index.js
@@ -38,8 +38,6 @@ function getReleaseURL(version = "0.10.0") {
 }
 
 async function fetchReviewdog(version = "0.10.0") {
-  const releaseUrl = getReleaseURL(version);
-
   const reviewdogPath = await tc.downloadTool(getReleaseURL(version));
   const reviewdogExtractedFolder = await tc.extractTar(
     reviewdogPath,