diff --git a/app/Util/ActivityPub/Validator/StoryValidator.php b/app/Util/ActivityPub/Validator/StoryValidator.php
new file mode 100644
index 000000000..362b121ca
--- /dev/null
+++ b/app/Util/ActivityPub/Validator/StoryValidator.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace App\Util\ActivityPub\Validator;
+
+use Validator;
+use Illuminate\Validation\Rule;
+
+class StoryValidator {
+
+	public static function validate($payload)
+	{
+		$valid = Validator::make($payload, [
+			'@context' => 'required',
+			'id' => 'required|string',
+			'type' => [
+				'required',
+				Rule::in(['Story'])
+			],
+			'to' => 'required',
+			'attributedTo' => 'required|url',
+			'published' => 'required|date',
+			'expiresAt' => 'required|date',
+			'duration' => 'required|integer|min:1|max:300',
+			'can_react' => 'required|boolean',
+			'can_reply' => 'required|boolean',
+			'attachment' => 'required',
+			'attachment.type' => 'required|in:Image,Video',
+			'attachment.url' => 'required|url',
+			'attachment.mediaType' => 'required'
+		])->passes();
+
+		return $valid;
+	}
+}
diff --git a/tests/Unit/ActivityPub/StoryValidationTest.php b/tests/Unit/ActivityPub/StoryValidationTest.php
new file mode 100644
index 000000000..0dd756f16
--- /dev/null
+++ b/tests/Unit/ActivityPub/StoryValidationTest.php
@@ -0,0 +1,84 @@
+<?php
+
+namespace Tests\Unit\ActivityPub;
+
+use PHPUnit\Framework\TestCase;
+use App\Util\ActivityPub\Validator\StoryValidator;
+
+class StoryValidationTest extends TestCase
+{
+	public function setUp(): void
+	{
+		parent::setUp();
+
+		$this->activity = json_decode('{"@context":"https://www.w3.org/ns/activitystreams","id":"https://pixelfed.test/stories/dansup/338581222496276480","type":"Story","to":["https://pixelfed.test/users/dansup/followers"],"cc":[],"attributedTo":"https://pixelfed.test/users/dansup","published":"2021-09-01T07:20:53+00:00","expiresAt":"2021-09-02T07:21:04+00:00","duration":3,"can_reply":true,"can_react":true,"attachment":{"type":"Image","url":"https://pixelfed.test/storage/_esm.t3/xV9/R2LF1xwhAA/011oqKVPDySG3WCPW7yIs2wobvccoITMnG/yT_FZX04f2DCzTA3K8HD2OS7FptXTHPiE1c_ZkHASBQ8UlPKH4.jpg","mediaType":"image/jpeg"}}', true);
+	}
+
+	/** @test */
+	public function schemaTest()
+	{
+		$this->assertTrue(StoryValidator::validate($this->activity));
+	}
+
+	/** @test */
+	public function invalidContext()
+	{
+		$activity = $this->activity;
+		unset($activity['@context']);
+		$activity['@@context'] = 'https://www.w3.org/ns/activitystreams';
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function missingContext()
+	{
+		$activity = $this->activity;
+		unset($activity['@context']);
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function missingId()
+	{
+		$activity = $this->activity;
+		unset($activity['id']);
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function missingType()
+	{
+		$activity = $this->activity;
+		unset($activity['type']);
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function invalidType()
+	{
+		$activity = $this->activity;
+		$activity['type'] = 'Store';
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function missingTo()
+	{
+		$activity = $this->activity;
+		unset($activity['to']);
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+	/** @test */
+	public function missingTimestamps()
+	{
+		$activity = $this->activity;
+		unset($activity['published']);
+		$this->assertFalse(StoryValidator::validate($activity));
+
+		$activity = $this->activity;
+		unset($activity['expiresAt']);
+		$this->assertFalse(StoryValidator::validate($activity));
+	}
+
+}