diff --git a/redisvl/extensions/router/semantic.py b/redisvl/extensions/router/semantic.py
index 16472615..2a45f811 100644
--- a/redisvl/extensions/router/semantic.py
+++ b/redisvl/extensions/router/semantic.py
@@ -885,6 +885,15 @@ def _make_filter_queries(ids: list[str]) -> list[FilterQuery]:
         queries = []
 
         for id in ids:
+            if not id:
+                # `Tag(...) == ""` renders as the match-all `*`, so an empty id
+                # would match every reference in the index. Callers take the
+                # first row of each query's results, which turns this into
+                # returning -- and, from delete_route_references, deleting -- an
+                # arbitrary reference the caller never named.
+                raise ValueError(
+                    "reference ids must be non-empty strings; received an empty id"
+                )
             fe = Tag("reference_id") == id
             fq = FilterQuery(
                 return_fields=["reference_id", "route_name", "reference"],
diff --git a/tests/integration/test_semantic_router.py b/tests/integration/test_semantic_router.py
index 1bc709b6..d6d9ba74 100644
--- a/tests/integration/test_semantic_router.py
+++ b/tests/integration/test_semantic_router.py
@@ -12,6 +12,7 @@
     RoutingConfig,
 )
 from redisvl.redis.connection import is_version_gte
+from redisvl.redis.utils import convert_bytes
 from tests.conftest import skip_if_no_redis_search, skip_if_redis_version_below
 
 pytestmark = pytest.mark.requires_hf
@@ -728,6 +729,26 @@ def test_get_route_references(semantic_router):
         semantic_router.get_route_references()
 
 
+def test_empty_reference_id_deletes_nothing(semantic_router):
+    # An empty id used to render the match-all `*`, and because the caller reads
+    # the first row of each query's results it removed an arbitrary reference
+    # rather than the one asked for.
+    prefix = semantic_router._index.schema.index.prefix
+    keys_before = set(
+        convert_bytes(semantic_router._index._redis_client.keys(f"{prefix}*"))
+    )
+
+    with pytest.raises(ValueError):
+        semantic_router.delete_route_references(reference_ids=[""])
+    with pytest.raises(ValueError):
+        semantic_router.get_route_references(reference_ids=[""])
+
+    keys_after = set(
+        convert_bytes(semantic_router._index._redis_client.keys(f"{prefix}*"))
+    )
+    assert keys_after == keys_before
+
+
 def test_delete_route_references(semantic_router):
     # Get references for a specific route
     deleted = semantic_router.delete_route_references(route_name="greeting")
diff --git a/tests/unit/test_semantic_router_queries.py b/tests/unit/test_semantic_router_queries.py
new file mode 100644
index 00000000..4eb4938c
--- /dev/null
+++ b/tests/unit/test_semantic_router_queries.py
@@ -0,0 +1,29 @@
+"""Hermetic tests for SemanticRouter's reference-id filter construction.
+
+`_make_filter_queries` is a static method that touches neither Redis nor a
+vectorizer, so its behaviour is testable without the router's integration
+fixtures -- which matters because a defect here silently deletes data.
+"""
+
+import pytest
+
+from redisvl.extensions.router.semantic import SemanticRouter
+
+
+def test_reference_id_query_is_scoped_to_the_id():
+    (query,) = SemanticRouter._make_filter_queries(["abc123"])
+    assert str(query._filter_expression) == "@reference_id:{abc123}"
+
+
+@pytest.mark.parametrize("empty", ["", None], ids=["empty_string", "none"])
+def test_empty_reference_id_is_rejected_rather_than_matching_everything(empty):
+    # `Tag("reference_id") == ""` renders as `*`. Callers read the first row of
+    # each query's results, so a match-all here returns -- and, from
+    # delete_route_references, deletes -- a reference nobody named.
+    with pytest.raises(ValueError, match="non-empty"):
+        SemanticRouter._make_filter_queries([empty])
+
+
+def test_one_empty_id_rejects_the_whole_batch():
+    with pytest.raises(ValueError, match="non-empty"):
+        SemanticRouter._make_filter_queries(["abc123", "", "def456"])