diff --git a/docs/SCHEMAS.md b/docs/SCHEMAS.md
index 8bcdf6d..af943b1 100644
--- a/docs/SCHEMAS.md
+++ b/docs/SCHEMAS.md
@@ -29,6 +29,9 @@ Required fields:
 | `host` | string | Hostname at emission time. |
 | `<event_type>` | object | Payload, under a key equal to `event_type` (e.g. `alert` holds an `enodia.alert.v1` object). |
 
+The reference encoder lives in `enodia_sentinel/event.py`
+(`build_event`, `from_alert`); `tests/test_event_envelope.py` pins the contract.
+
 ## `enodia.alert.v1`
 
 Single detection object, used inside alert snapshots and by commands such as
diff --git a/enodia_sentinel/event.py b/enodia_sentinel/event.py
index cd4d454..c8ba930 100644
--- a/enodia_sentinel/event.py
+++ b/enodia_sentinel/event.py
@@ -44,3 +44,8 @@ def build_event(
         "host": host,
         event_type: payload,
     }
+
+
+def from_alert(alert, *, host: str | None = None, timestamp: str | None = None) -> dict:
+    """Wrap an ``Alert`` (via its ``to_dict()``) in an ``alert`` event envelope."""
+    return build_event("alert", alert.to_dict(), host=host, timestamp=timestamp)
diff --git a/tests/test_event_envelope.py b/tests/test_event_envelope.py
index debeec8..e98cad8 100644
--- a/tests/test_event_envelope.py
+++ b/tests/test_event_envelope.py
@@ -42,6 +42,20 @@ class TestEventEnvelope(unittest.TestCase):
     def test_event_types_is_closed_set(self):
         self.assertEqual(event.EVENT_TYPES, frozenset({"alert", "incident", "status"}))
 
+    def test_from_alert_wraps_alert_payload(self):
+        from enodia_sentinel.alert import Alert, Severity
+        alert = Alert(
+            Severity.CRITICAL, "reverse_shell", "rsh:4242",
+            "pid=4242 peer=[8.8.8.8:4444]", (4242,),
+            sid=100010, classtype="command-and-control")
+        env = event.from_alert(alert, host="host-a")
+        self.assertEqual(env["event_type"], "alert")
+        self.assertEqual(env["host"], "host-a")
+        # Payload is the untouched enodia.alert.v1 object.
+        self.assertEqual(env["alert"], alert.to_dict())
+        self.assertEqual(env["alert"]["signature"], "reverse_shell")
+        self.assertEqual(env["alert"]["sid"], 100010)
+
 
 if __name__ == "__main__":
     unittest.main()