diff --git a/cloud/tests/test_longfunc_inventory.py b/cloud/tests/test_longfunc_inventory.py
new file mode 100644
index 0000000..45cc008
--- /dev/null
+++ b/cloud/tests/test_longfunc_inventory.py
@@ -0,0 +1,81 @@
+"""A13: >100-line method inventory (17 items, checkable in code).
+
+The split summary's section 4 listed 16 >100-line methods; the
+missing 17th is ``FullAutoMixin._full_auto_execute``
+(``cloud/handler_fullauto.py:182-304``, 123 lines). This test
+pins the full 17-method list by AST over ``cloud/handler_*.py``
+plus ``cloud/server.py`` -- no external summary document is the
+source of truth, the code itself is.
+
+Counting rule, stated because a naive AST count gives 18:
+the 17 are class methods. The 18th >100-line definition,
+``handler_support.migrate_tasks_table`` (module-level function,
+not a mixin method), is asserted separately as the ONLY
+module-level >100-line definition, so the 17/18 difference is
+explained, not hidden. No method is split by this batch:
+internal splitting stays at 0 items.
+"""
+
+import ast
+import unittest
+from pathlib import Path
+
+EXPECTED_METHODS = {
+    ("handler_admin.py", "AdminMixin._task_pr"),
+    ("handler_admin.py", "AdminMixin._metrics"),
+    ("handler_browser.py", "BrowserMixin._browser_stream"),
+    ("handler_core.py", "TaskCoreMixin._create_task"),
+    ("handler_core.py", "TaskCoreMixin._create_followup"),
+    ("handler_fullauto.py", "FullAutoMixin._full_auto_execute"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._task_thread_read"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._deliver_to_thread"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._task_wait"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._merge_task"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._loop_run"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._release_task"),
+    ("handler_lifecycle.py", "TaskLifecycleMixin._continue_task"),
+    ("handler_webhook.py", "WebhookMixin._handle_github_webhook"),
+    ("server.py", "CloudControlPlaneHandler._dispatch_task_route"),
+    ("server.py", "CloudControlPlaneHandler._dispatch"),
+    ("server.py", "CloudControlPlaneHandler._dispatch_project"),
+}
+
+
+class LongFuncInventoryTestCase(unittest.TestCase):
+    def test_seventeen_long_methods_including_full_auto_execute(self):
+        cloud_dir = Path(__file__).resolve().parents[1]
+        methods = set()
+        module_funcs = set()
+        for path in sorted(cloud_dir.glob("handler_*.py")) + [
+                cloud_dir / "server.py"]:
+            tree = ast.parse(path.read_text(encoding="utf-8"))
+            for node in tree.body:
+                if isinstance(node, ast.ClassDef):
+                    for member in node.body:
+                        if isinstance(member, (ast.FunctionDef,
+                                               ast.AsyncFunctionDef)):
+                            lines = (member.end_lineno
+                                     - member.lineno + 1)
+                            if lines > 100:
+                                methods.add(
+                                    (path.name,
+                                     "%s.%s" % (node.name, member.name)))
+                elif isinstance(node, (ast.FunctionDef,
+                                       ast.AsyncFunctionDef)):
+                    lines = node.end_lineno - node.lineno + 1
+                    if lines > 100:
+                        module_funcs.add((path.name, node.name))
+        self.assertEqual(len(EXPECTED_METHODS), 17)
+        self.assertIn(
+            ("handler_fullauto.py", "FullAutoMixin._full_auto_execute"),
+            EXPECTED_METHODS)
+        self.assertEqual(methods, EXPECTED_METHODS)
+        # The single non-method >100-line definition, documented
+        # rather than silently dropped from the count.
+        self.assertEqual(
+            module_funcs,
+            {("handler_support.py", "migrate_tasks_table")})
+
+
+if __name__ == "__main__":
+    unittest.main()