diff --git a/weed/s3api/s3lifecycle/dispatcher/toproto_test.go b/weed/s3api/s3lifecycle/dispatcher/toproto_test.go
new file mode 100644
index 000000000..03b608a65
--- /dev/null
+++ b/weed/s3api/s3lifecycle/dispatcher/toproto_test.go
@@ -0,0 +1,85 @@
+package dispatcher
+
+import (
+	"testing"
+
+	"github.com/seaweedfs/seaweedfs/weed/pb/s3_lifecycle_pb"
+	"github.com/seaweedfs/seaweedfs/weed/s3api/s3lifecycle"
+	"github.com/seaweedfs/seaweedfs/weed/s3api/s3lifecycle/router"
+	"github.com/stretchr/testify/assert"
+)
+
+// toProtoActionKind / toProtoIdentity are the worker-side CAS-witness
+// converters; getting them wrong silently breaks the LifecycleDelete
+// flow because the server's identity check always fails. These tests
+// pin the full mapping so a new ActionKind added in s3lifecycle but
+// forgotten here can't slip through as ACTION_KIND_UNSPECIFIED.
+
+func TestToProtoActionKind_AllKnownKindsMap(t *testing.T) {
+	cases := []struct {
+		in   s3lifecycle.ActionKind
+		want s3_lifecycle_pb.ActionKind
+	}{
+		{s3lifecycle.ActionKindExpirationDays, s3_lifecycle_pb.ActionKind_EXPIRATION_DAYS},
+		{s3lifecycle.ActionKindExpirationDate, s3_lifecycle_pb.ActionKind_EXPIRATION_DATE},
+		{s3lifecycle.ActionKindNoncurrentDays, s3_lifecycle_pb.ActionKind_NONCURRENT_DAYS},
+		{s3lifecycle.ActionKindNewerNoncurrent, s3_lifecycle_pb.ActionKind_NEWER_NONCURRENT},
+		{s3lifecycle.ActionKindAbortMPU, s3_lifecycle_pb.ActionKind_ABORT_MPU},
+		{s3lifecycle.ActionKindExpiredDeleteMarker, s3_lifecycle_pb.ActionKind_EXPIRED_DELETE_MARKER},
+	}
+	for _, c := range cases {
+		t.Run(c.in.String(), func(t *testing.T) {
+			assert.Equal(t, c.want, toProtoActionKind(c.in))
+		})
+	}
+}
+
+func TestToProtoActionKind_UnspecifiedAndUnknownFallToUnspecified(t *testing.T) {
+	// Both the in-package zero value and a future kind not listed in
+	// the switch must collapse to ACTION_KIND_UNSPECIFIED so the server
+	// can reject with FATAL rather than silently dispatch a wrong kind.
+	assert.Equal(t, s3_lifecycle_pb.ActionKind_ACTION_KIND_UNSPECIFIED,
+		toProtoActionKind(s3lifecycle.ActionKindUnspecified))
+	assert.Equal(t, s3_lifecycle_pb.ActionKind_ACTION_KIND_UNSPECIFIED,
+		toProtoActionKind(s3lifecycle.ActionKind(999)))
+}
+
+func TestToProtoIdentity_NilReturnsNil(t *testing.T) {
+	// LifecycleDelete treats a nil ExpectedIdentity as "no CAS"; the
+	// converter must preserve that signal rather than emit an empty
+	// non-nil identity that would force a re-fetch + comparison.
+	assert.Nil(t, toProtoIdentity(nil))
+}
+
+func TestToProtoIdentity_AllFieldsCopied(t *testing.T) {
+	in := &router.EntryIdentity{
+		MtimeNs:      1700000000_000_000_123,
+		Size:         4096,
+		HeadFid:      "1,abc",
+		ExtendedHash: []byte{0xde, 0xad, 0xbe, 0xef},
+	}
+	out := toProtoIdentity(in)
+	if out == nil {
+		t.Fatal("non-nil input must produce non-nil output")
+	}
+	assert.Equal(t, in.MtimeNs, out.MtimeNs)
+	assert.Equal(t, in.Size, out.Size)
+	assert.Equal(t, in.HeadFid, out.HeadFid)
+	assert.Equal(t, in.ExtendedHash, out.ExtendedHash)
+}
+
+func TestToProtoIdentity_EmptyFieldsSurvive(t *testing.T) {
+	// A bootstrap-fresh entry can land at the dispatcher with zero
+	// MtimeNs / Size / no HeadFid — the converter must still produce a
+	// non-nil identity so the server treats it as a real CAS witness
+	// rather than the no-CAS sentinel.
+	in := &router.EntryIdentity{}
+	out := toProtoIdentity(in)
+	if out == nil {
+		t.Fatal("zero-valued identity must still produce non-nil")
+	}
+	assert.Zero(t, out.MtimeNs)
+	assert.Zero(t, out.Size)
+	assert.Empty(t, out.HeadFid)
+	assert.Empty(t, out.ExtendedHash)
+}