diff --git a/.github/workflows/push-image.yml b/.github/workflows/push-image.yml
index c463e93..f491fed 100644
--- a/.github/workflows/push-image.yml
+++ b/.github/workflows/push-image.yml
@@ -81,21 +81,49 @@ jobs:
         env:
           IMAGE_NAME: ${{ matrix.image }}
           REGISTRY_ALIAS: ${{ vars.AWS_REGISTRY_ALIAS }}
+        shell: bash
         run: |
           set -euo pipefail
 
-          # Query ECR Public for existing image tags matching semver pattern
-          TAGS=$(aws ecr-public describe-image-tags \
-            --region us-east-1 \
-            --repository-name "${IMAGE_NAME}" \
-            --no-paginate \
-            --query 'imageTagDetails[].imageTag' \
-            --output text 2>/dev/null || echo "")
+          if [[ -z "${IMAGE_NAME:-}" ]]; then
+            echo "ERROR: IMAGE_NAME environment variable is not set" >&2
+            exit 1
+          fi
 
-          # Find the highest semver tag
-          LATEST_VERSION=$(echo "$TAGS" | tr '\t' '\n' | grep -E '^[0-9]+\.[0-9]+\.[0-9]+$' | sort -V | tail -n 1 || true)
+          # Verify the repository exists — fail immediately if it doesn't.
+          aws ecr-public describe-repositories \
+            --region us-east-1 \
+            --repository-names "${IMAGE_NAME}" > /dev/null 2>&1 || {
+              echo "ERROR: Repository ${IMAGE_NAME} does not exist in ECR Public." >&2
+              exit 1
+            }
 
-          if [[ -z "$LATEST_VERSION" ]]; then
+          # Query existing image tags.
+          RESPONSE=$(aws ecr-public describe-image-tags \
+            --region us-east-1 \
+            --repository-name "${IMAGE_NAME}" \
+            --no-paginate) || {
+              echo "ERROR: Failed to query image tags for ${IMAGE_NAME}." >&2
+              exit 1
+            }
+
+          TAGS=$(echo "$RESPONSE" | jq -r '.imageTagDetails') || {
+            echo "ERROR: Failed to parse ECR response as JSON:" >&2
+            echo "$RESPONSE" >&2
+            exit 1
+          }
+
+          # Find the highest semver tag using jq sort
+          LATEST_VERSION=$(echo "$TAGS" | \
+            jq -r '[.[] | select(.imageTag | test("^[0-9]+\\.[0-9]+\\.[0-9]+$"))] | sort_by(.imageTag | split(".") | map(tonumber))' | \
+            jq -r '.[-1].imageTag') || {
+              echo "ERROR: Failed to extract latest version from tags:" >&2
+              echo "$TAGS" >&2
+              exit 1
+            }
+
+          # If no semver tags exist yet, start at 1.0.0; otherwise bump patch.
+          if [[ -z "$LATEST_VERSION" || "$LATEST_VERSION" == "null" ]]; then
             NEXT_VERSION="1.0.0"
           else
             IFS='.' read -r MAJOR MINOR PATCH <<< "$LATEST_VERSION"