diff --git a/tests/test_rule_usage_wiring.py b/tests/test_rule_usage_wiring.py
index 952b29b..d589587 100644
--- a/tests/test_rule_usage_wiring.py
+++ b/tests/test_rule_usage_wiring.py
@@ -735,14 +735,27 @@ def test_the_hook_and_the_route_agree_on_every_parameter_name():
     import re
 
     hook = Path("plugin/hooks/scribe_tool_rules.sh").read_text()
+    defs = Path("plugin/hooks/scribe_defs.sh").read_text()
     route = Path("src/scribe/routes/plugin.py").read_text()
     handler = route.split("async def pre_tool_rules")[1].split("\n@plugin_bp")[0]
 
     sent = set(re.findall(r"[?&]([a-z_]+)=", hook))
-    assert sent == {"tool", "command", "repo", "exclude_rule_ids"}, sent
+    assert sent == {"tool", "command", "exclude_rule_ids"}, sent
 
-    # `repo` is read by the shared _project_scope() helper, not inline.
+    # The project-scope key is the shared helper's to choose (#4085): the hook
+    # splices in `scribe_scope_query`'s output, which is `repo=` inside a git
+    # repo and `project_id=` where a `.scribe` marker names the project. Both
+    # halves are one contract with the route, so both are pinned.
+    assert "scribe_scope_query" in hook, "hook no longer asks for a project scope"
+    assert set(re.findall(r"printf '([a-z_]+)=", defs)) == {"repo", "project_id"}
+
+    # Both scope keys are read by the shared _project_scope() helper, not inline.
     assert "_project_scope()" in handler
+    scope = route.split("async def _project_scope")[1].split("\n@plugin_bp")[0]
+    for arg in ("project_id", "repo"):
+        assert f'request.args.get("{arg}"' in scope, (
+            f"the hooks can send {arg!r} and the route never reads it"
+        )
     for arg in ("tool", "command", "exclude_rule_ids"):
         assert f'request.args.get("{arg}")' in handler, (
             f"the hook sends {arg!r} and the route never reads it"
diff --git a/tests/test_write_path_trigger.py b/tests/test_write_path_trigger.py
index d6dd323..84af7cd 100644
--- a/tests/test_write_path_trigger.py
+++ b/tests/test_write_path_trigger.py
@@ -931,10 +931,16 @@ def test_route_reads_every_arg_the_hook_sends():
         assert f'request.args.get("{arg}"' in src, f"route ignores {arg}"
 
     hook = HOOK.read_text()
-    for arg in ("path=", "code=", "repo=", "exclude_ids=", "exclude_sync_ids=",
-                "shapes="):
+    for arg in ("path=", "code=", "exclude_ids=", "exclude_sync_ids=", "shapes="):
         assert arg in hook, f"hook never sends {arg}"
 
+    # The project-scope key is no longer spelled in the hook: since #4085 it is
+    # whichever of `repo=` / `project_id=` scribe_scope_query picks, so the hook
+    # splices in its output and the helper is the other half of the contract.
+    assert "scribe_scope_query" in hook, "hook no longer asks for a project scope"
+    defs = (HOOK.parent / "scribe_defs.sh").read_text()
+    assert set(re.findall(r"printf '([a-z_]+)=", defs)) == {"repo", "project_id"}
+
 
 def test_route_resolves_repo_to_a_project_not_to_a_location_filter():
     """A snippet's `repo` is a label the operator typed; the hook sends a git