diff --git a/edb/server/protocol/auth_ext/config.py b/edb/server/protocol/auth_ext/config.py
index 40561e9f38c4..90105d044a85 100644
--- a/edb/server/protocol/auth_ext/config.py
+++ b/edb/server/protocol/auth_ext/config.py
@@ -87,6 +87,7 @@ class MagicLinkProviderConfig(ProviderConfig):
     name: Literal["builtin::local_magic_link"]
     token_time_to_live: statypes.Duration
 
+
 @dataclass
 class WebhookConfig:
     events: list[str]
diff --git a/edb/server/protocol/auth_ext/webhook.py b/edb/server/protocol/auth_ext/webhook.py
index 261d2d6ed056..6ae756b496a6 100644
--- a/edb/server/protocol/auth_ext/webhook.py
+++ b/edb/server/protocol/auth_ext/webhook.py
@@ -139,4 +139,11 @@ async def send(
     )
     result = json.loads(result_json)
 
-    return result[0]["id"]
+    match result[0]["id"]:
+        case str(id):
+            return id
+        case _:
+            raise ValueError(
+                "Expected single result with 'id' string property, got "
+                f"{result[0]!r}"
+            )