diff --git a/protocol/types.go b/protocol/types.go
index 7a2846e..f95861e 100644
--- a/protocol/types.go
+++ b/protocol/types.go
@@ -2307,10 +2307,14 @@ func (w WASMWorkload) Validate() error {
 }
 
 func validateProviderComponentRef(name, value string) error {
-	value = strings.TrimSpace(value)
-	if value == "" {
+	raw := value
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
 		return fmt.Errorf("%s is required", name)
 	}
+	if raw != trimmed {
+		return fmt.Errorf("%s must not contain surrounding whitespace", name)
+	}
 	if strings.ContainsAny(value, " \t\r\n\x00") {
 		return fmt.Errorf("%s must not contain whitespace or NUL", name)
 	}
@@ -4856,10 +4860,14 @@ func validateScopedRef(name, value, scheme string) error {
 }
 
 func validateComponentRef(name, value string) error {
-	value = strings.TrimSpace(value)
-	if value == "" {
+	raw := value
+	trimmed := strings.TrimSpace(value)
+	if trimmed == "" {
 		return fmt.Errorf("%s is required", name)
 	}
+	if raw != trimmed {
+		return fmt.Errorf("%s must not contain surrounding whitespace", name)
+	}
 	for _, prefix := range []string{"artifact://", "content://", "provider://"} {
 		if strings.HasPrefix(value, prefix) && !strings.ContainsAny(value, " \t\r\n\x00") {
 			return nil
diff --git a/protocol/types_test.go b/protocol/types_test.go
index b293f40..2cc6747 100644
--- a/protocol/types_test.go
+++ b/protocol/types_test.go
@@ -152,6 +152,20 @@ func TestServiceWorkloadRejectsUnsafeShape(t *testing.T) {
 	}
 }
 
+func TestServiceWorkloadRejectsComponentRefWhitespace(t *testing.T) {
+	workload := protocol.ServiceWorkload{
+		ComponentRef:    " provider://workflow-plugin-compute-service/service-runtime",
+		ComponentDigest: "sha256:" + strings.Repeat("a", 64),
+		Command:         []string{"serve", "--port", "8080"},
+		Ports:           []protocol.ServicePort{{Name: "http", Port: 8080, Protocol: "http"}},
+		HealthCheck:     protocol.HealthCheck{Kind: "http", Path: "/healthz", IntervalSeconds: 5, TimeoutSeconds: 2},
+		Ingress:         protocol.IngressPolicy{Mode: "private", AuthRequired: true},
+	}
+	if err := workload.Validate(); err == nil || !strings.Contains(err.Error(), "surrounding whitespace") {
+		t.Fatalf("service workload accepted whitespace-padded component_ref: %v", err)
+	}
+}
+
 func TestWorkloadSpecValidatesNodeServiceWorkload(t *testing.T) {
 	endpoint := "node.example.invalid:30303"
 	workload := protocol.WorkloadSpec{
@@ -184,6 +198,27 @@ func TestWorkloadSpecValidatesNodeServiceWorkload(t *testing.T) {
 	}
 }
 
+func TestNodeServiceWorkloadRejectsComponentRefWhitespace(t *testing.T) {
+	endpoint := "node.example.invalid:30303"
+	workload := protocol.NodeServiceWorkload{
+		ComponentRef:    "provider://workflow-plugin-compute-service/node-runtime ",
+		ComponentDigest: "sha256:" + strings.Repeat("b", 64),
+		Chain:           "ethereum",
+		Network:         "sepolia",
+		DataDirRef:      "volume://nodes/sepolia",
+		RPCSecretRef:    "secret://nodes/sepolia/rpc",
+		PeerPolicy: protocol.PeerPolicy{
+			Mode:            "allowlist",
+			AllowedPeers:    []string{endpoint},
+			EgressAllowlist: []string{endpoint},
+		},
+		HealthCheck: protocol.HealthCheck{Kind: "command", Command: []string{"node", "status"}, IntervalSeconds: 10, TimeoutSeconds: 3},
+	}
+	if err := workload.Validate(); err == nil || !strings.Contains(err.Error(), "surrounding whitespace") {
+		t.Fatalf("node-service workload accepted whitespace-padded component_ref: %v", err)
+	}
+}
+
 func TestNodeServiceWorkloadRejectsMissingHealthAndUnsafePeers(t *testing.T) {
 	workload := protocol.NodeServiceWorkload{
 		ImageRef:     "ghcr.io/gocodealone/node@sha256:" + strings.Repeat("c", 64),