diff --git a/README.md b/README.md
index e69de29..c7dabfd 100644
--- a/README.md
+++ b/README.md
@@ -0,0 +1 @@
+Creates or updates a .env file with specified environment variables and outputs its base64-encoded content.
diff --git a/action.yml b/action.yml
index c21cdcd..a723d6a 100644
--- a/action.yml
+++ b/action.yml
@@ -1,47 +1,50 @@
-name: 'Prepare Environment'
-description: 'Prepares .env file with necessary variables'
+name: 'Prepare Env File'
+description: 'Creates or updates a .env file with specified environment variables and outputs its base64-encoded content.'
+
 inputs:
   stack_name:
-    description: 'Stack name'
+    description: 'The name of the stack to set in the .env file.'
     required: true
+
 outputs:
   exists:
-    description: 'Whether .env file exists'
-    value: 'true'
+    description: 'Indicates whether the .env file existed before running this action.'
+    value: ${{ steps.prepare.outputs.exists }}
   content:
-    description: 'Base64 encoded content of .env file'
+    description: 'Base64-encoded content of the resulting .env file.'
     value: ${{ steps.encode.outputs.content }}
+
 runs:
   using: 'composite'
   steps:
     - id: prepare
       shell: bash
       run: |
-        echo "DEBUG: Checking if .env file exists"
-        if [ ! -f ".env" ]; then
-          echo "DEBUG: .env file not found, creating new one"
+        set -euo pipefail
+        if [ -f ".env" ]; then
+          echo "exists=true" >> $GITHUB_OUTPUT
+          echo "DEBUG: .env file exists. Updating STACK_NAME."
+        else
+          echo "exists=false" >> $GITHUB_OUTPUT
+          echo "DEBUG: .env file does not exist. Creating new .env file."
           touch .env
-        else
-          echo "DEBUG: .env file already exists, using existing file"
         fi
 
-        echo "DEBUG: Checking if STACK_NAME is already set in .env"
-        if grep -q "STACK_NAME=" .env; then
-          echo "DEBUG: STACK_NAME found in .env, updating value to '${{ inputs.stack_name }}'"
-          sed -i "s/STACK_NAME=.*/STACK_NAME=${{ inputs.stack_name }}/" .env
+        if grep -q "^STACK_NAME=" .env; then
+          sed -i "s/^STACK_NAME=.*/STACK_NAME=${{ inputs.stack_name }}/" .env
+          echo "DEBUG: Updated existing STACK_NAME to '${{ inputs.stack_name }}'."
         else
-          echo "DEBUG: STACK_NAME not found in .env, adding value '${{ inputs.stack_name }}'"
           echo "STACK_NAME=${{ inputs.stack_name }}" >> .env
+          echo "DEBUG: Added STACK_NAME='${{ inputs.stack_name }}' to .env."
         fi
 
-        echo "DEBUG: Final .env file content:"
+        echo "DEBUG: Final .env content:"
         cat .env
 
     - id: encode
       shell: bash
       run: |
-        echo "DEBUG: Encoding .env file to base64"
+        set -euo pipefail
         ENV_BASE64=$(base64 -w 0 .env)
         echo "content=$ENV_BASE64" >> $GITHUB_OUTPUT
-        echo "DEBUG: .env file encoded successfully"
-
+        echo "DEBUG: Successfully encoded .env file to base64."
\ No newline at end of file