diff --git a/cloud/src/Ingest/EventValidator.php b/cloud/src/Ingest/EventValidator.php
index a119935..9f26d07 100644
--- a/cloud/src/Ingest/EventValidator.php
+++ b/cloud/src/Ingest/EventValidator.php
@@ -22,6 +22,16 @@ final class EventValidator
         elseif (count($snaps) > 3) $errors[] = 'too_many:snapshots';
         else foreach ($snaps as $s) if (!is_string($s)) { $errors[] = 'bad:snapshot_item'; break; }
 
+        // Type guards for required fields
+        if (!is_string($p['device_id'])) $errors[] = 'bad:device_id';
+        if (!is_string($p['camera_id'])) $errors[] = 'bad:camera_id';
+        if (!is_numeric($p['occurred_at'])) $errors[] = 'bad:occurred_at';
+
+        // Type guards for optional fields
+        if (isset($p['track_id']) && !is_numeric($p['track_id'])) $errors[] = 'bad:track_id';
+        if (isset($p['zone_id']) && !is_string($p['zone_id'])) $errors[] = 'bad:zone_id';
+        if (isset($p['duration_s']) && !is_numeric($p['duration_s'])) $errors[] = 'bad:duration_s';
+
         if ($errors) return ['ok' => false, 'errors' => $errors, 'clean' => []];
 
         $clean = [
diff --git a/cloud/tests/EventValidatorTest.php b/cloud/tests/EventValidatorTest.php
index 0bcfcca..d1612d3 100644
--- a/cloud/tests/EventValidatorTest.php
+++ b/cloud/tests/EventValidatorTest.php
@@ -31,4 +31,24 @@ final class EventValidatorTest extends TestCase
         $p = $this->valid(); $p['snapshots'] = ['a', 'b', 'c', 'd'];
         $this->assertFalse(EventValidator::validate($p)['ok']);
     }
+    public function testRejectsNonNumericOccurredAt(): void {
+        $p = $this->valid(); $p['occurred_at'] = ['bad'];
+        $this->assertFalse(EventValidator::validate($p)['ok']);
+    }
+    public function testRejectsNonStringDeviceId(): void {
+        $p = $this->valid(); $p['device_id'] = ['x'];
+        $this->assertFalse(EventValidator::validate($p)['ok']);
+    }
+    public function testRejectsNonArraySnapshots(): void {
+        $p = $this->valid(); $p['snapshots'] = 'notarray';
+        $this->assertFalse(EventValidator::validate($p)['ok']);
+    }
+    public function testRejectsNonStringSnapshotItem(): void {
+        $p = $this->valid(); $p['snapshots'] = [123];
+        $this->assertFalse(EventValidator::validate($p)['ok']);
+    }
+    public function testRejectsNonStringZoneId(): void {
+        $p = $this->valid(); $p['zone_id'] = ['z'];
+        $this->assertFalse(EventValidator::validate($p)['ok']);
+    }
 }