fix(cron): clarify schedule is required for create in tool schema

tests/cron/test_cronjob_schema.py

@@ -0,0 +1,41 @@
+"""Tests for the cronjob tool schema shape.
+
+Guards the description text that flags ``schedule`` (and ``prompt``) as
+REQUIRED for ``action=create`` — the load-bearing fix for description-driven
+models (e.g. Grok) that omit schedule when the schema only lists ``action``
+in ``required[]``. See issue #32427 / PR #32448.
+"""
+
+from __future__ import annotations
+
+
+def test_cronjob_schema_action_description_flags_create_requirements():
+    """`action` description must state schedule + prompt are required for create."""
+    from tools.cronjob_tools import CRONJOB_SCHEMA
+
+    action_desc = CRONJOB_SCHEMA["parameters"]["properties"]["action"]["description"]
+    assert "action=create" in action_desc
+    assert "schedule" in action_desc
+    assert "REQUIRED" in action_desc
+
+
+def test_cronjob_schema_schedule_description_flags_required_for_create():
+    """`schedule` description must explicitly state REQUIRED for action=create."""
+    from tools.cronjob_tools import CRONJOB_SCHEMA
+
+    schedule_desc = CRONJOB_SCHEMA["parameters"]["properties"]["schedule"]["description"]
+    assert "REQUIRED" in schedule_desc
+    assert "action=create" in schedule_desc
+
+
+def test_cronjob_schema_required_array_unchanged():
+    """`required[]` stays minimal — `action` only.
+
+    The schema intentionally does NOT promote schedule/prompt into the
+    top-level required array because they're only mandatory for
+    action=create, not for list/remove/pause/etc. The description text
+    carries the conditional requirement instead.
+    """
+    from tools.cronjob_tools import CRONJOB_SCHEMA
+
+    assert CRONJOB_SCHEMA["parameters"]["required"] == ["action"]

tools/cronjob_tools.py

@@ -706,7 +706,7 @@ def cronjob(
         "properties": {
             "action": {
                 "type": "string",
-                "description": "One of: create, list, update, pause, resume, remove, run"
+                "description": "One of: create, list, update, pause, resume, remove, run. When action=create, the 'schedule' and 'prompt' fields are REQUIRED."
             },
             "job_id": {
                 "type": "string",
@@ -718,7 +718,7 @@ def cronjob(
             },
             "schedule": {
                 "type": "string",
-                "description": "For create/update: '30m', 'every 2h', '0 9 * * *', or ISO timestamp"
+                "description": "REQUIRED for action=create. For create/update: '30m', 'every 2h', '0 9 * * *', or ISO timestamp. Examples: '30m' (every 30 minutes), 'every 2h' (every 2 hours), '0 9 * * *' (daily at 9am), '2026-06-01T09:00:00' (one-shot). You MUST include this field when action=create."
             },
             "name": {
                 "type": "string",