diff --git a/packages/tests/cozy-lib-tests/templates/tests/keda-scaledobject-arg.yaml b/packages/tests/cozy-lib-tests/templates/tests/keda-scaledobject-arg.yaml
new file mode 100644
index 000000000..a38d3df4d
--- /dev/null
+++ b/packages/tests/cozy-lib-tests/templates/tests/keda-scaledobject-arg.yaml
@@ -0,0 +1,10 @@
+{{- if .Values.omit -}}
+{{- /* Build a fully-valid argument dict, then drop exactly one required field
+       named by .Values.omit, to exercise each fail-closed guard in isolation. */ -}}
+{{- $ref := dict "apiVersion" "postgresql.cnpg.io/v1" "kind" "Cluster" "name" "db" -}}
+{{- if eq .Values.omit "kind" }}{{- $_ := unset $ref "kind" }}{{- end -}}
+{{- if eq .Values.omit "apiVersion" }}{{- $_ := unset $ref "apiVersion" }}{{- end -}}
+{{- $arg := dict "name" "db" "scaleTargetRef" $ref "minReplicaCount" 2 "maxReplicaCount" 6 "serverAddress" "http://vmselect.example.svc:8481/select/0/prometheus" "query" "sum(x) + 150" "threshold" "150" -}}
+{{- $arg = unset $arg .Values.omit -}}
+{{ include "cozy-lib.keda.scaledObject" $arg }}
+{{- end -}}
diff --git a/packages/tests/cozy-lib-tests/tests/keda_scaledobject_test.yaml b/packages/tests/cozy-lib-tests/tests/keda_scaledobject_test.yaml
index 4a1e31d08..efaf21713 100644
--- a/packages/tests/cozy-lib-tests/tests/keda_scaledobject_test.yaml
+++ b/packages/tests/cozy-lib-tests/tests/keda_scaledobject_test.yaml
@@ -6,6 +6,7 @@ templates:
   - templates/tests/keda-scaledobject-nondict.yaml
   - templates/tests/keda-scaledobject-params.yaml
   - templates/tests/keda-scaledobject-bounds.yaml
+  - templates/tests/keda-scaledobject-arg.yaml
 
 release:
   name: postgres-db
@@ -117,3 +118,38 @@ tests:
     asserts:
       - failedTemplate:
           errorMessage: "cozy-lib.keda.scaledObject: maxReplicaCount must be >= minReplicaCount"
+
+
+  # Remaining fail-closed guards (one required field dropped per case via the
+  # keda-scaledobject-arg fixture) so the helper's full rejection contract is
+  # executable-documented, not just sampled.
+  - it: fails closed when name is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: name}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: name is required"}
+  - it: fails closed when scaleTargetRef.kind is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: kind}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: scaleTargetRef.kind is required"}
+  - it: fails closed when scaleTargetRef.apiVersion is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: apiVersion}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: scaleTargetRef.apiVersion is required"}
+  - it: fails closed when query is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: query}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: query is required"}
+  - it: fails closed when threshold is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: threshold}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: threshold is required"}
+  - it: fails closed when serverAddress is missing
+    templates: [templates/tests/keda-scaledobject-arg.yaml]
+    set: {omit: serverAddress}
+    asserts:
+      - failedTemplate: {errorMessage: "cozy-lib.keda.scaledObject: serverAddress is required"}