Update README

README.md

@@ -1 +1,45 @@
-# setup-veryl
+# setup-veryl
+
+[![Actions Status](https://github.com/veryl-lang/setup-veryl/workflows/Tests/badge.svg)](https://github.com/veryl-lang/setup-veryl/actions)
+
+This action downloads a prebuilt [Veryl](https://veryl-lang.org/) binary and adds it to the `PATH`.
+
+## Usage
+
+By default, this action downloads the latest version of Veryl.
+
+```yaml
+name: My workflow
+on: [push, pull_request]
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+    - uses: veryl-lang/setup-veryl@v1
+    - run: veryl check
+```
+
+Version specification through `version` can be used.
+
+```yaml
+    - uses: veryl-lang/setup-veryl@v1
+      with:
+        version: 0.7.2
+```
+
+## License
+
+Licensed under either of
+
+ * Apache License, Version 2.0, ([LICENSE-APACHE](LICENSE-APACHE) or http://www.apache.org/licenses/LICENSE-2.0)
+ * MIT license ([LICENSE-MIT](LICENSE-MIT) or http://opensource.org/licenses/MIT)
+
+at your option.
+
+### Contribution
+
+Unless you explicitly state otherwise, any contribution intentionally
+submitted for inclusion in the work by you, as defined in the Apache-2.0
+license, shall be dual licensed as above, without any additional terms or
+conditions.