diff --git a/packages/backend/src/server/api/endpoints/channels/create.ts b/packages/backend/src/server/api/endpoints/channels/create.ts
index 4962bd3da..1a55cebe4 100644
--- a/packages/backend/src/server/api/endpoints/channels/create.ts
+++ b/packages/backend/src/server/api/endpoints/channels/create.ts
@@ -7,6 +7,8 @@ import { ApiError } from '../../error.js';
 export const meta = {
 	tags: ['channels'],
 
+	description: 'Creates a new channel with the current user as its administrator.',
+
 	requireCredential: true,
 
 	kind: 'write:channels',
@@ -32,14 +34,13 @@ export const paramDef = {
 
 // eslint-disable-next-line import/no-default-export
 export default define(meta, paramDef, async (ps, user) => {
-	let banner = null;
 	if (ps.bannerId != null) {
-		banner = await DriveFiles.findOneBy({
+		const bannerExists = await DriveFiles.countBy({
 			id: ps.bannerId,
 			userId: user.id,
 		});
 
-		if (banner == null) throw new ApiError('NO_SUCH_FILE');
+		if (!bannerExists) throw new ApiError('NO_SUCH_FILE');
 	}
 
 	const channel = await Channels.insert({
@@ -47,8 +48,8 @@ export default define(meta, paramDef, async (ps, user) => {
 		createdAt: new Date(),
 		userId: user.id,
 		name: ps.name,
-		description: ps.description || null,
-		bannerId: banner ? banner.id : null,
+		description: ps.description,
+		bannerId: ps.bannerId,
 	} as Channel).then(x => Channels.findOneByOrFail(x.identifiers[0]));
 
 	return await Channels.pack(channel, user);