diff --git a/trio/_core/_mock_clock.py b/trio/_core/_mock_clock.py
index fe35298631..27a5829076 100644
--- a/trio/_core/_mock_clock.py
+++ b/trio/_core/_mock_clock.py
@@ -150,7 +150,7 @@ def deadline_to_sleep_time(self, deadline: float) -> float:
         else:
             return 999999999
 
-    def jump(self, seconds) -> None:
+    def jump(self, seconds: float) -> None:
         """Manually advance the clock by the given number of seconds.
 
         Args:
diff --git a/trio/_tests/verify_types.json b/trio/_tests/verify_types.json
index 9c71ddd58a..55ba3b32d7 100644
--- a/trio/_tests/verify_types.json
+++ b/trio/_tests/verify_types.json
@@ -7,11 +7,11 @@
     "warningCount": 0
   },
   "typeCompleteness": {
-    "completenessScore": 0.9170653907496013,
+    "completenessScore": 0.9186602870813397,
     "exportedSymbolCounts": {
       "withAmbiguousType": 0,
-      "withKnownType": 575,
-      "withUnknownType": 52
+      "withKnownType": 576,
+      "withUnknownType": 51
     },
     "ignoreUnknownTypesFromImports": true,
     "missingClassDocStringCount": 1,
@@ -46,12 +46,11 @@
     ],
     "otherSymbolCounts": {
       "withAmbiguousType": 3,
-      "withKnownType": 600,
-      "withUnknownType": 63
+      "withKnownType": 602,
+      "withUnknownType": 61
     },
     "packageName": "trio",
     "symbols": [
-      "trio._core._mock_clock.MockClock.jump",
       "trio._core._run.Nursery.start",
       "trio._core._run.Nursery.start_soon",
       "trio._core._run.TaskStatus.__repr__",