diff --git a/src/aio_fleet/alerts.py b/src/aio_fleet/alerts.py
index da73a32..7260d70 100644
--- a/src/aio_fleet/alerts.py
+++ b/src/aio_fleet/alerts.py
@@ -16,6 +16,7 @@
     "upstream-monitor",
     "upstream-update",
 }
+HTTP_USER_AGENT = "aio-fleet-alerts/1.0"
 
 
 @dataclass(frozen=True)
@@ -222,7 +223,7 @@ def send_webhook(
     request = urllib.request.Request(
         webhook_url,
         data=body,
-        headers=headers,
+        headers={**headers, "User-Agent": HTTP_USER_AGENT},
         method="POST",
     )
     with urllib.request.urlopen(request, timeout=20) as response:  # nosec B310
diff --git a/tests/test_alerts.py b/tests/test_alerts.py
index 53da032..3d4528f 100644
--- a/tests/test_alerts.py
+++ b/tests/test_alerts.py
@@ -73,6 +73,7 @@ def fake_urlopen(request: urllib.request.Request, timeout: int):
     body = json.loads(seen[0].data.decode())  # type: ignore[union-attr]
     assert body["dedupe_key"] == "registry-audit:fleet"  # nosec B101
     assert body["status"] == "failure"  # nosec B101
+    assert seen[0].headers["User-agent"] == "aio-fleet-alerts/1.0"  # nosec B101
 
 
 def test_discord_webhook_uses_discord_payload(monkeypatch) -> None:
@@ -107,6 +108,7 @@ def fake_urlopen(request: urllib.request.Request, timeout: int):
     body = json.loads(seen[0].data.decode())  # type: ignore[union-attr]
     assert body["allowed_mentions"]["parse"] == []  # nosec B101
     assert body["content"].startswith("aio-fleet: upstream updates")  # nosec B101
+    assert seen[0].headers["User-agent"] == "aio-fleet-alerts/1.0"  # nosec B101
     assert body["embeds"][0]["fields"][2]["value"] == (  # nosec B101
         "upstream-monitor:fleet:all"
     )