diff --git a/README.md b/README.md
index 94bc53c..ce3bb00 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,55 @@
-# Trivy GitHub Action
+# Trivy Action
 
+> [GitHub Action](https://github.com/features/actions) for Trivy
+
+## Table of Contents
+
+- [Usage](#usage)
+  - [Workflow](#workflow)
+- [Customizing](#customizing)
+  - [Inputs](#inputs)
+
+## Usage
+
+### Workflow
+
+```yaml
+name: build
+on:
+  push:
+    branches:
+      - master
+  pull_request:
+jobs:
+  build:
+    name: Build
+    runs-on: ubuntu-18.04
+    steps:
+      - name: Setup Go
+        uses: actions/setup-go@v1
+        with:
+          go-version: 1.14
+      - name: Checkout code
+        uses: actions/checkout@v2
+      - name: Build an image from Dockerfile
+        run: |
+          docker build -t docker.io/my-organization/my-app:${{ github.sha }}
+      - name: Run vulnerability scanner
+        uses: aquasecurity/trivy-action@0.0.4
+        with:
+          image-ref: 'docker.io/my-organization/my-app:${{ github.sha }}'
+          format: 'table'
+          exit-code: '1'
+```
+
+## Customizing
+
+### inputs
+
+Following inputs can be used as `step.with` keys:
+
+| Name        | Type   | Default | Description                               |
+|-------------|--------|---------|-------------------------------------------|
+| `image-ref` | String |         | Image reference, e.g. `alpine:3.10.2`     |
+| `format`    | String | `table` | Output format (`table`, `json`)           |
+| `exit-code` | String | `0`     | exit code when vulnerabilities were found |
diff --git a/action.yaml b/action.yaml
index 9b50515..231d570 100644
--- a/action.yaml
+++ b/action.yaml
@@ -13,9 +13,13 @@ inputs:
     description: 'output format (table, json)'
     required: false
     default: 'table'
+  version:
+    description: 'version of Trivy to use'
+    required: false
+    default: 'latest'
 runs:
   using: 'docker'
-  image: 'docker://docker.io/aquasec/trivy:latest'
+  image: 'docker://docker.io/aquasec/trivy:${{ inputs.version }}'
   args:
     - 'image'
     - '--format=${{ inputs.format }}'