diff --git a/packages/misskey-js/generator/src/generator.ts b/packages/misskey-js/generator/src/generator.ts
index 4ae00a4522..88f2ae9ee9 100644
--- a/packages/misskey-js/generator/src/generator.ts
+++ b/packages/misskey-js/generator/src/generator.ts
@@ -96,15 +96,11 @@ async function generateEndpoints(
 				endpoint.request = req;
 
 				const reqType = new EndpointReqMediaType(path, req);
-				endpointReqMediaTypesSet.add(reqType.getMediaType());
-				endpointReqMediaTypes.push(reqType);
-			} else {
-				endpointReqMediaTypesSet.add('application/json');
-				endpointReqMediaTypes.push(new EndpointReqMediaType(path, undefined, 'application/json'));
+				if (reqType.getMediaType() !== 'application/json') {
+					endpointReqMediaTypesSet.add(reqType.getMediaType());
+					endpointReqMediaTypes.push(reqType);
+				}
 			}
-		} else {
-			endpointReqMediaTypesSet.add('application/json');
-			endpointReqMediaTypes.push(new EndpointReqMediaType(path, undefined, 'application/json'));
 		}
 
 		if (operation.responses && isResponseObject(operation.responses['200']) && operation.responses['200'].content) {
@@ -158,16 +154,19 @@ async function generateEndpoints(
 	endpointOutputLine.push('');
 
 	function generateEndpointReqMediaTypesType() {
-		return `Record<keyof Endpoints, ${[...endpointReqMediaTypesSet].map((t) => `'${t}'`).join(' | ')}>`;
+		return `{ [K in keyof Endpoints]?: ${[...endpointReqMediaTypesSet].map((t) => `'${t}'`).join(' | ')}; }`;
 	}
 
-	endpointOutputLine.push(`export const endpointReqTypes: ${generateEndpointReqMediaTypesType()} = {`);
+	endpointOutputLine.push(`/**
+ * NOTE: The content-type for all endpoints not listed here is application/json.
+ */`);
+	endpointOutputLine.push('export const endpointReqTypes = {');
 
 	endpointOutputLine.push(
 		...endpointReqMediaTypes.map(it => '\t' + it.toLine()),
 	);
 
-	endpointOutputLine.push('};');
+	endpointOutputLine.push(`} as const satisfies ${generateEndpointReqMediaTypesType()};`);
 	endpointOutputLine.push('');
 
 	await writeFile(endpointOutputPath, endpointOutputLine.join('\n'));
diff --git a/packages/misskey-js/src/api.ts b/packages/misskey-js/src/api.ts
index ea1df57f3d..659a29a221 100644
--- a/packages/misskey-js/src/api.ts
+++ b/packages/misskey-js/src/api.ts
@@ -56,6 +56,10 @@ export class APIClient {
 		return obj !== null && typeof obj === 'object' && !Array.isArray(obj);
 	}
 
+	private assertSpecialEpReqType(ep: keyof Endpoints): ep is keyof typeof endpointReqTypes {
+		return ep in endpointReqTypes;
+	}
+
 	public request<E extends keyof Endpoints, P extends Endpoints[E]['req']>(
 		endpoint: E,
 		params: P = {} as P,
@@ -63,9 +67,10 @@ export class APIClient {
 	): Promise<SwitchCaseResponseType<E, P>> {
 		return new Promise((resolve, reject) => {
 			let mediaType = 'application/json';
-			if (endpoint in endpointReqTypes) {
+			if (this.assertSpecialEpReqType(endpoint) && endpointReqTypes[endpoint] != null) {
 				mediaType = endpointReqTypes[endpoint];
 			}
+			
 			let payload: FormData | string = '{}';
 
 			if (mediaType === 'application/json') {
@@ -100,7 +105,7 @@ export class APIClient {
 				method: 'POST',
 				body: payload,
 				headers: {
-					'Content-Type': endpointReqTypes[endpoint],
+					'Content-Type': mediaType,
 				},
 				credentials: 'omit',
 				cache: 'no-cache',
diff --git a/packages/misskey-js/src/autogen/endpoint.ts b/packages/misskey-js/src/autogen/endpoint.ts
index be41951e4d..8fbdbbb629 100644
--- a/packages/misskey-js/src/autogen/endpoint.ts
+++ b/packages/misskey-js/src/autogen/endpoint.ts
@@ -955,384 +955,9 @@ export type Endpoints = {
 	'reversi/verify': { req: ReversiVerifyRequest; res: ReversiVerifyResponse };
 }
 
-export const endpointReqTypes: Record<keyof Endpoints, 'application/json' | 'multipart/form-data'> = {
-	'admin/meta': 'application/json',
-	'admin/abuse-user-reports': 'application/json',
-	'admin/abuse-report/notification-recipient/list': 'application/json',
-	'admin/abuse-report/notification-recipient/show': 'application/json',
-	'admin/abuse-report/notification-recipient/create': 'application/json',
-	'admin/abuse-report/notification-recipient/update': 'application/json',
-	'admin/abuse-report/notification-recipient/delete': 'application/json',
-	'admin/accounts/create': 'application/json',
-	'admin/accounts/delete': 'application/json',
-	'admin/accounts/find-by-email': 'application/json',
-	'admin/ad/create': 'application/json',
-	'admin/ad/delete': 'application/json',
-	'admin/ad/list': 'application/json',
-	'admin/ad/update': 'application/json',
-	'admin/announcements/create': 'application/json',
-	'admin/announcements/delete': 'application/json',
-	'admin/announcements/list': 'application/json',
-	'admin/announcements/update': 'application/json',
-	'admin/avatar-decorations/create': 'application/json',
-	'admin/avatar-decorations/delete': 'application/json',
-	'admin/avatar-decorations/list': 'application/json',
-	'admin/avatar-decorations/update': 'application/json',
-	'admin/delete-all-files-of-a-user': 'application/json',
-	'admin/unset-user-avatar': 'application/json',
-	'admin/unset-user-banner': 'application/json',
-	'admin/drive/clean-remote-files': 'application/json',
-	'admin/drive/cleanup': 'application/json',
-	'admin/drive/files': 'application/json',
-	'admin/drive/show-file': 'application/json',
-	'admin/emoji/add-aliases-bulk': 'application/json',
-	'admin/emoji/add': 'application/json',
-	'admin/emoji/copy': 'application/json',
-	'admin/emoji/delete-bulk': 'application/json',
-	'admin/emoji/delete': 'application/json',
-	'admin/emoji/import-zip': 'application/json',
-	'admin/emoji/list-remote': 'application/json',
-	'admin/emoji/list': 'application/json',
-	'admin/emoji/remove-aliases-bulk': 'application/json',
-	'admin/emoji/set-aliases-bulk': 'application/json',
-	'admin/emoji/set-category-bulk': 'application/json',
-	'admin/emoji/set-license-bulk': 'application/json',
-	'admin/emoji/update': 'application/json',
-	'admin/federation/delete-all-files': 'application/json',
-	'admin/federation/refresh-remote-instance-metadata': 'application/json',
-	'admin/federation/remove-all-following': 'application/json',
-	'admin/federation/update-instance': 'application/json',
-	'admin/get-index-stats': 'application/json',
-	'admin/get-table-stats': 'application/json',
-	'admin/get-user-ips': 'application/json',
-	'admin/invite/create': 'application/json',
-	'admin/invite/list': 'application/json',
-	'admin/promo/create': 'application/json',
-	'admin/queue/clear': 'application/json',
-	'admin/queue/deliver-delayed': 'application/json',
-	'admin/queue/inbox-delayed': 'application/json',
-	'admin/queue/promote': 'application/json',
-	'admin/queue/stats': 'application/json',
-	'admin/relays/add': 'application/json',
-	'admin/relays/list': 'application/json',
-	'admin/relays/remove': 'application/json',
-	'admin/reset-password': 'application/json',
-	'admin/resolve-abuse-user-report': 'application/json',
-	'admin/send-email': 'application/json',
-	'admin/server-info': 'application/json',
-	'admin/show-moderation-logs': 'application/json',
-	'admin/show-user': 'application/json',
-	'admin/show-users': 'application/json',
-	'admin/suspend-user': 'application/json',
-	'admin/unsuspend-user': 'application/json',
-	'admin/update-meta': 'application/json',
-	'admin/delete-account': 'application/json',
-	'admin/update-user-note': 'application/json',
-	'admin/roles/create': 'application/json',
-	'admin/roles/delete': 'application/json',
-	'admin/roles/list': 'application/json',
-	'admin/roles/show': 'application/json',
-	'admin/roles/update': 'application/json',
-	'admin/roles/assign': 'application/json',
-	'admin/roles/unassign': 'application/json',
-	'admin/roles/update-default-policies': 'application/json',
-	'admin/roles/users': 'application/json',
-	'admin/system-webhook/create': 'application/json',
-	'admin/system-webhook/delete': 'application/json',
-	'admin/system-webhook/list': 'application/json',
-	'admin/system-webhook/show': 'application/json',
-	'admin/system-webhook/update': 'application/json',
-	'announcements': 'application/json',
-	'announcements/show': 'application/json',
-	'antennas/create': 'application/json',
-	'antennas/delete': 'application/json',
-	'antennas/list': 'application/json',
-	'antennas/notes': 'application/json',
-	'antennas/show': 'application/json',
-	'antennas/update': 'application/json',
-	'ap/get': 'application/json',
-	'ap/show': 'application/json',
-	'app/create': 'application/json',
-	'app/show': 'application/json',
-	'auth/accept': 'application/json',
-	'auth/session/generate': 'application/json',
-	'auth/session/show': 'application/json',
-	'auth/session/userkey': 'application/json',
-	'blocking/create': 'application/json',
-	'blocking/delete': 'application/json',
-	'blocking/list': 'application/json',
-	'channels/create': 'application/json',
-	'channels/featured': 'application/json',
-	'channels/follow': 'application/json',
-	'channels/followed': 'application/json',
-	'channels/owned': 'application/json',
-	'channels/show': 'application/json',
-	'channels/timeline': 'application/json',
-	'channels/unfollow': 'application/json',
-	'channels/update': 'application/json',
-	'channels/favorite': 'application/json',
-	'channels/unfavorite': 'application/json',
-	'channels/my-favorites': 'application/json',
-	'channels/search': 'application/json',
-	'charts/active-users': 'application/json',
-	'charts/ap-request': 'application/json',
-	'charts/drive': 'application/json',
-	'charts/federation': 'application/json',
-	'charts/instance': 'application/json',
-	'charts/notes': 'application/json',
-	'charts/user/drive': 'application/json',
-	'charts/user/following': 'application/json',
-	'charts/user/notes': 'application/json',
-	'charts/user/pv': 'application/json',
-	'charts/user/reactions': 'application/json',
-	'charts/users': 'application/json',
-	'clips/add-note': 'application/json',
-	'clips/remove-note': 'application/json',
-	'clips/create': 'application/json',
-	'clips/delete': 'application/json',
-	'clips/list': 'application/json',
-	'clips/notes': 'application/json',
-	'clips/show': 'application/json',
-	'clips/update': 'application/json',
-	'clips/favorite': 'application/json',
-	'clips/unfavorite': 'application/json',
-	'clips/my-favorites': 'application/json',
-	'drive': 'application/json',
-	'drive/files': 'application/json',
-	'drive/files/attached-notes': 'application/json',
-	'drive/files/check-existence': 'application/json',
+/**
+ * NOTE: The content-type for all endpoints not listed here is application/json.
+ */
+export const endpointReqTypes = {
 	'drive/files/create': 'multipart/form-data',
-	'drive/files/delete': 'application/json',
-	'drive/files/find-by-hash': 'application/json',
-	'drive/files/find': 'application/json',
-	'drive/files/show': 'application/json',
-	'drive/files/update': 'application/json',
-	'drive/files/upload-from-url': 'application/json',
-	'drive/folders': 'application/json',
-	'drive/folders/create': 'application/json',
-	'drive/folders/delete': 'application/json',
-	'drive/folders/find': 'application/json',
-	'drive/folders/show': 'application/json',
-	'drive/folders/update': 'application/json',
-	'drive/stream': 'application/json',
-	'email-address/available': 'application/json',
-	'endpoint': 'application/json',
-	'endpoints': 'application/json',
-	'export-custom-emojis': 'application/json',
-	'federation/followers': 'application/json',
-	'federation/following': 'application/json',
-	'federation/instances': 'application/json',
-	'federation/show-instance': 'application/json',
-	'federation/update-remote-user': 'application/json',
-	'federation/users': 'application/json',
-	'federation/stats': 'application/json',
-	'following/create': 'application/json',
-	'following/delete': 'application/json',
-	'following/update': 'application/json',
-	'following/update-all': 'application/json',
-	'following/invalidate': 'application/json',
-	'following/requests/accept': 'application/json',
-	'following/requests/cancel': 'application/json',
-	'following/requests/list': 'application/json',
-	'following/requests/reject': 'application/json',
-	'gallery/featured': 'application/json',
-	'gallery/popular': 'application/json',
-	'gallery/posts': 'application/json',
-	'gallery/posts/create': 'application/json',
-	'gallery/posts/delete': 'application/json',
-	'gallery/posts/like': 'application/json',
-	'gallery/posts/show': 'application/json',
-	'gallery/posts/unlike': 'application/json',
-	'gallery/posts/update': 'application/json',
-	'get-online-users-count': 'application/json',
-	'get-avatar-decorations': 'application/json',
-	'hashtags/list': 'application/json',
-	'hashtags/search': 'application/json',
-	'hashtags/show': 'application/json',
-	'hashtags/trend': 'application/json',
-	'hashtags/users': 'application/json',
-	'i': 'application/json',
-	'i/2fa/done': 'application/json',
-	'i/2fa/key-done': 'application/json',
-	'i/2fa/password-less': 'application/json',
-	'i/2fa/register-key': 'application/json',
-	'i/2fa/register': 'application/json',
-	'i/2fa/update-key': 'application/json',
-	'i/2fa/remove-key': 'application/json',
-	'i/2fa/unregister': 'application/json',
-	'i/apps': 'application/json',
-	'i/authorized-apps': 'application/json',
-	'i/claim-achievement': 'application/json',
-	'i/change-password': 'application/json',
-	'i/delete-account': 'application/json',
-	'i/export-blocking': 'application/json',
-	'i/export-following': 'application/json',
-	'i/export-mute': 'application/json',
-	'i/export-notes': 'application/json',
-	'i/export-clips': 'application/json',
-	'i/export-favorites': 'application/json',
-	'i/export-user-lists': 'application/json',
-	'i/export-antennas': 'application/json',
-	'i/favorites': 'application/json',
-	'i/gallery/likes': 'application/json',
-	'i/gallery/posts': 'application/json',
-	'i/import-blocking': 'application/json',
-	'i/import-following': 'application/json',
-	'i/import-muting': 'application/json',
-	'i/import-user-lists': 'application/json',
-	'i/import-antennas': 'application/json',
-	'i/notifications': 'application/json',
-	'i/notifications-grouped': 'application/json',
-	'i/page-likes': 'application/json',
-	'i/pages': 'application/json',
-	'i/pin': 'application/json',
-	'i/read-all-unread-notes': 'application/json',
-	'i/read-announcement': 'application/json',
-	'i/regenerate-token': 'application/json',
-	'i/registry/get-all': 'application/json',
-	'i/registry/get-detail': 'application/json',
-	'i/registry/get': 'application/json',
-	'i/registry/keys-with-type': 'application/json',
-	'i/registry/keys': 'application/json',
-	'i/registry/remove': 'application/json',
-	'i/registry/scopes-with-domain': 'application/json',
-	'i/registry/set': 'application/json',
-	'i/revoke-token': 'application/json',
-	'i/signin-history': 'application/json',
-	'i/unpin': 'application/json',
-	'i/update-email': 'application/json',
-	'i/update': 'application/json',
-	'i/move': 'application/json',
-	'i/webhooks/create': 'application/json',
-	'i/webhooks/list': 'application/json',
-	'i/webhooks/show': 'application/json',
-	'i/webhooks/update': 'application/json',
-	'i/webhooks/delete': 'application/json',
-	'invite/create': 'application/json',
-	'invite/delete': 'application/json',
-	'invite/list': 'application/json',
-	'invite/limit': 'application/json',
-	'meta': 'application/json',
-	'emojis': 'application/json',
-	'emoji': 'application/json',
-	'miauth/gen-token': 'application/json',
-	'mute/create': 'application/json',
-	'mute/delete': 'application/json',
-	'mute/list': 'application/json',
-	'renote-mute/create': 'application/json',
-	'renote-mute/delete': 'application/json',
-	'renote-mute/list': 'application/json',
-	'my/apps': 'application/json',
-	'notes': 'application/json',
-	'notes/children': 'application/json',
-	'notes/clips': 'application/json',
-	'notes/conversation': 'application/json',
-	'notes/create': 'application/json',
-	'notes/delete': 'application/json',
-	'notes/favorites/create': 'application/json',
-	'notes/favorites/delete': 'application/json',
-	'notes/featured': 'application/json',
-	'notes/global-timeline': 'application/json',
-	'notes/hybrid-timeline': 'application/json',
-	'notes/local-timeline': 'application/json',
-	'notes/mentions': 'application/json',
-	'notes/polls/recommendation': 'application/json',
-	'notes/polls/vote': 'application/json',
-	'notes/reactions': 'application/json',
-	'notes/reactions/create': 'application/json',
-	'notes/reactions/delete': 'application/json',
-	'notes/renotes': 'application/json',
-	'notes/replies': 'application/json',
-	'notes/search-by-tag': 'application/json',
-	'notes/search': 'application/json',
-	'notes/show': 'application/json',
-	'notes/state': 'application/json',
-	'notes/thread-muting/create': 'application/json',
-	'notes/thread-muting/delete': 'application/json',
-	'notes/timeline': 'application/json',
-	'notes/translate': 'application/json',
-	'notes/unrenote': 'application/json',
-	'notes/user-list-timeline': 'application/json',
-	'notifications/create': 'application/json',
-	'notifications/flush': 'application/json',
-	'notifications/mark-all-as-read': 'application/json',
-	'notifications/test-notification': 'application/json',
-	'page-push': 'application/json',
-	'pages/create': 'application/json',
-	'pages/delete': 'application/json',
-	'pages/featured': 'application/json',
-	'pages/like': 'application/json',
-	'pages/show': 'application/json',
-	'pages/unlike': 'application/json',
-	'pages/update': 'application/json',
-	'flash/create': 'application/json',
-	'flash/delete': 'application/json',
-	'flash/featured': 'application/json',
-	'flash/like': 'application/json',
-	'flash/show': 'application/json',
-	'flash/unlike': 'application/json',
-	'flash/update': 'application/json',
-	'flash/my': 'application/json',
-	'flash/my-likes': 'application/json',
-	'ping': 'application/json',
-	'pinned-users': 'application/json',
-	'promo/read': 'application/json',
-	'roles/list': 'application/json',
-	'roles/show': 'application/json',
-	'roles/users': 'application/json',
-	'roles/notes': 'application/json',
-	'request-reset-password': 'application/json',
-	'reset-db': 'application/json',
-	'reset-password': 'application/json',
-	'server-info': 'application/json',
-	'stats': 'application/json',
-	'sw/show-registration': 'application/json',
-	'sw/update-registration': 'application/json',
-	'sw/register': 'application/json',
-	'sw/unregister': 'application/json',
-	'test': 'application/json',
-	'username/available': 'application/json',
-	'users': 'application/json',
-	'users/clips': 'application/json',
-	'users/followers': 'application/json',
-	'users/following': 'application/json',
-	'users/gallery/posts': 'application/json',
-	'users/get-frequently-replied-users': 'application/json',
-	'users/featured-notes': 'application/json',
-	'users/lists/create': 'application/json',
-	'users/lists/delete': 'application/json',
-	'users/lists/list': 'application/json',
-	'users/lists/pull': 'application/json',
-	'users/lists/push': 'application/json',
-	'users/lists/show': 'application/json',
-	'users/lists/favorite': 'application/json',
-	'users/lists/unfavorite': 'application/json',
-	'users/lists/update': 'application/json',
-	'users/lists/create-from-public': 'application/json',
-	'users/lists/update-membership': 'application/json',
-	'users/lists/get-memberships': 'application/json',
-	'users/notes': 'application/json',
-	'users/pages': 'application/json',
-	'users/flashs': 'application/json',
-	'users/reactions': 'application/json',
-	'users/recommendation': 'application/json',
-	'users/relation': 'application/json',
-	'users/report-abuse': 'application/json',
-	'users/search-by-username-and-host': 'application/json',
-	'users/search': 'application/json',
-	'users/show': 'application/json',
-	'users/achievements': 'application/json',
-	'users/update-memo': 'application/json',
-	'fetch-rss': 'application/json',
-	'fetch-external-resources': 'application/json',
-	'retention': 'application/json',
-	'bubble-game/register': 'application/json',
-	'bubble-game/ranking': 'application/json',
-	'reversi/cancel-match': 'application/json',
-	'reversi/games': 'application/json',
-	'reversi/match': 'application/json',
-	'reversi/invitations': 'application/json',
-	'reversi/show-game': 'application/json',
-	'reversi/surrender': 'application/json',
-	'reversi/verify': 'application/json',
-};
+} as const satisfies { [K in keyof Endpoints]?: 'multipart/form-data'; };