diff --git a/.github/templates/README.tpl b/.github/templates/README.tpl
index 9e6ed1b..73fa02d 100644
--- a/.github/templates/README.tpl
+++ b/.github/templates/README.tpl
@@ -21,6 +21,19 @@ version 0.11+ and 0.12+ but may work for others.)
 | --- |
 {{- end }}
 
+### Upgrade v0 to v1
+
+Release v1 contains following breaking changes:
+
+- default value of `output-file` has been changed to `README.md`
+- default value of `template` has been changed to
+
+  ```text
+  <!-- BEGIN_TF_DOCS -->
+  {{"{{"}} .Content {{"}}"}}
+  <!-- END_TF_DOCS -->
+  ```
+
 ## Usage
 
 To use terraform-docs github action, configure a YAML workflow file, e.g.
diff --git a/README.md b/README.md
index 82633d9..851da78 100644
--- a/README.md
+++ b/README.md
@@ -8,9 +8,22 @@ branch.
 
 ## Version
 
-`v0.11.0` (uses [terraform-docs] v0.16.0, which is supported and tested on Terraform
+`v1.0.0` (uses [terraform-docs] v0.16.0, which is supported and tested on Terraform
 version 0.11+ and 0.12+ but may work for others.)
 
+### Upgrade v0 to v1
+
+Release v1 contains following breaking changes:
+
+- default value of `output-file` has been changed to `README.md`
+- default value of `template` has been changed to
+
+  ```text
+  <!-- BEGIN_TF_DOCS -->
+  {{ .Content }}
+  <!-- END_TF_DOCS -->
+  ```
+
 ## Usage
 
 To use terraform-docs github action, configure a YAML workflow file, e.g.
@@ -29,7 +42,7 @@ jobs:
         ref: ${{ github.event.pull_request.head.ref }}
 
     - name: Render terraform docs inside the README.md and push changes back to PR branch
-      uses: terraform-docs/gh-actions@v0.11.0
+      uses: terraform-docs/gh-actions@v1.0.0
       with:
         working-dir: .
         output-file: README.md
@@ -134,7 +147,7 @@ To enable you need to ensure a few things first:
 
 ```yaml
 - name: Generate TF Docs
-  uses: terraform-docs/gh-actions@v0.11.0
+  uses: terraform-docs/gh-actions@v1.0.0
   with:
     working-dir: .
 ```
@@ -143,7 +156,7 @@ To enable you need to ensure a few things first:
 
 ```yaml
 - name: Generate TF Docs
-  uses: terraform-docs/gh-actions@v0.11.0
+  uses: terraform-docs/gh-actions@v1.0.0
   with:
     working-dir: .,example1,example3/modules/test
 ```
@@ -152,7 +165,7 @@ To enable you need to ensure a few things first:
 
 ```yaml
 - name: Generate TF docs
-  uses: terraform-docs/gh-actions@v0.11.0
+  uses: terraform-docs/gh-actions@v1.0.0
   with:
     atlantis-file: atlantis.yaml
 ```
@@ -161,7 +174,7 @@ To enable you need to ensure a few things first:
 
 ```yaml
 - name: Generate TF docs
-  uses: terraform-docs/gh-actions@v0.11.0
+  uses: terraform-docs/gh-actions@v1.0.0
   with:
     find-dir: examples/
 ```
@@ -170,13 +183,13 @@ To enable you need to ensure a few things first:
 
 ```yaml
 - name: Generate TF docs
-  uses: terraform-docs/gh-actions@v0.11.0
+  uses: terraform-docs/gh-actions@v1.0.0
   with:
     working-dir: examples/
     recursive: true
     recursive-path: modules
 ```
 
-Complete examples can be found [here](https://github.com/terraform-docs/gh-actions/tree/v0.11.0/examples).
+Complete examples can be found [here](https://github.com/terraform-docs/gh-actions/tree/v1.0.0/examples).
 
 [terraform-docs]: https://github.com/terraform-docs/terraform-docs
diff --git a/action.yml b/action.yml
index c7a9131..cfb2b69 100644
--- a/action.yml
+++ b/action.yml
@@ -85,7 +85,7 @@ outputs:
 
 runs:
   using: docker
-  image: "docker://quay.io/terraform-docs/gh-actions:edge"
+  image: "docker://quay.io/terraform-docs/gh-actions:1.0.0"
   env:
     INPUT_WORKING_DIR: ${{ inputs.working-dir }}
     INPUT_ATLANTIS_FILE: ${{ inputs.atlantis-file }}