diff --git a/tests/test_knowledge_base_ast.py b/tests/test_knowledge_base_ast.py
new file mode 100644
index 00000000..287b7d00
--- /dev/null
+++ b/tests/test_knowledge_base_ast.py
@@ -0,0 +1,43 @@
+import sys
+from pathlib import Path
+
+sys.path.insert(0, str(Path(__file__).resolve().parent.parent / "scripts"))
+
+from knowledge_base import KnowledgeBase
+
+
+def test_ingest_python_file_extracts_ast_facts(tmp_path: Path) -> None:
+    source = tmp_path / "demo_module.py"
+    source.write_text(
+        "import os\n"
+        "from pathlib import Path\n\n"
+        "CONSTANT = 7\n\n"
+        "def helper(x):\n"
+        "    return x + 1\n\n"
+        "class Demo:\n"
+        "    def method(self):\n"
+        "        return helper(CONSTANT)\n"
+    )
+
+    kb = KnowledgeBase()
+    facts = kb.ingest_python_file(source)
+
+    assert facts, "AST ingestion should add symbolic facts"
+    assert kb.query("defines_function", "demo_module", "helper") == [{}]
+    assert kb.query("defines_class", "demo_module", "Demo") == [{}]
+    assert kb.query("defines_method", "Demo", "method") == [{}]
+    assert kb.query("imports", "demo_module", "os") == [{}]
+    assert kb.query("imports", "demo_module", "pathlib.Path") == [{}]
+    assert kb.query("defines_constant", "demo_module", "CONSTANT") == [{}]
+
+
+def test_ingest_python_file_rejects_invalid_syntax(tmp_path: Path) -> None:
+    broken = tmp_path / "broken.py"
+    broken.write_text("def nope(:\n    pass\n")
+
+    kb = KnowledgeBase()
+    try:
+        kb.ingest_python_file(broken)
+    except SyntaxError:
+        return
+    raise AssertionError("Expected SyntaxError for invalid Python source")