Escape time-like tokens in FTS queries

lancedb_store.py

@@ -125,6 +125,11 @@ def _sql_escape(value: str) -> str:
         """Escape single quotes for safe use in SQL WHERE clauses."""
         return value.replace("'", "''")
 
+    @staticmethod
+    def _escape_fts_query(query: str) -> str:
+        """Escape natural-language tokens Tantivy misreads as field syntax."""
+        return re.sub(r"(?<!\\):", r"\\:", query)
+
     @staticmethod
     def _validate_identifier(key: str) -> None:
         """Raise ValueError if *key* is not a safe SQL identifier."""
@@ -637,7 +642,7 @@ def keyword_search(
             table = self._vs.table
         except TableNotFoundError:
             return []  # Table not created yet — legitimately empty
-        q = table.search(query, query_type="fts")
+        q = table.search(self._escape_fts_query(query), query_type="fts")
         if where:
             q = q.where(where, prefilter=True)
         rows = q.limit(top_k).to_list()

tests/test_search.py

@@ -656,6 +656,31 @@ def test_prefilter_combined_source_and_folder():
         assert result[0].doc_id == "b.pdf"
 
 
+def test_keyword_search_escapes_time_like_tokens():
+    """FTS keyword search should handle time-like natural-language tokens."""
+    with tempfile.TemporaryDirectory() as tmpdir:
+        vec = [1.0] + [0.0] * 767
+        nodes = [
+            _make_node(
+                "appt.md",
+                "c:0",
+                "Appointment at 10:00 for the unit showing",
+                vec,
+                source_name="comm_messages",
+                status="active",
+            ),
+        ]
+        store = _build_store_with_fts(tmpdir, nodes)
+
+        hits = store.keyword_search(
+            "10:00 showing",
+            top_k=10,
+            where="lower(metadata.source_name) = 'comm_messages'",
+        )
+
+        assert [hit.doc_id for hit in hits] == ["appt.md"]
+
+
 def test_prefilter_complex_filter_ast():
     """Complex filter AST should restrict results before search scoring."""
     with tempfile.TemporaryDirectory() as tmpdir: