diff --git a/CHANGELOG.md b/CHANGELOG.md
index 99b51ffb9..ac4b6f05a 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -80,6 +80,7 @@
 - Feat: Playで直接投稿フォームを埋め込めるように(`Ui:C:postForm`)
 - Feat: クライアントを起動している間、デバイスの画面が自動でオフになるのを防ぐオプションを追加
 - Feat: 新しい実績を追加
+- Feat: リモートサーバーのAPIを叩く用の関数を追加（`Mk:apiExternal`）
 - Enhance: ノート詳細ページでリノート一覧、リアクション一覧タブを追加
 	- ノートのメニューからは当該項目は消えました
 - Enhance: センシティブなメディアを目立たせる設定を追加
diff --git a/packages/frontend/src/os.ts b/packages/frontend/src/os.ts
index 8aed5797e..8093335a2 100644
--- a/packages/frontend/src/os.ts
+++ b/packages/frontend/src/os.ts
@@ -5,8 +5,8 @@
 
 // TODO: なんでもかんでもos.tsに突っ込むのやめたいのでよしなに分割する
 
-import { pendingApiRequestsCount, api, apiGet } from '@/scripts/api.js';
-export { pendingApiRequestsCount, api, apiGet };
+import { pendingApiRequestsCount, api, apiExternal, apiGet } from '@/scripts/api.js';
+export { pendingApiRequestsCount, api, apiExternal, apiGet };
 import { Component, markRaw, Ref, ref, defineAsyncComponent } from 'vue';
 import { EventEmitter } from 'eventemitter3';
 import insertTextAtCursor from 'insert-text-at-cursor';
diff --git a/packages/frontend/src/scripts/aiscript/api.ts b/packages/frontend/src/scripts/aiscript/api.ts
index 9f60e52ce..f049a51b9 100644
--- a/packages/frontend/src/scripts/aiscript/api.ts
+++ b/packages/frontend/src/scripts/aiscript/api.ts
@@ -48,6 +48,16 @@ export function createAiScriptEnv(opts) {
 				return values.ERROR('request_failed', utils.jsToVal(err));
 			});
 		}),
+		'Mk:apiExternal': values.FN_NATIVE(async ([host, ep, param, token]) => {
+			utils.assertString(host);
+			utils.assertString(ep);
+			if (token) utils.assertString(token);
+			return os.apiExternal(host.value, ep.value, utils.valToJs(param), token?.value).then(res => {
+				return utils.jsToVal(res);
+			}, err => {
+				return values.ERROR('request_failed', utils.jsToVal(err));
+			});
+		}),
 		'Mk:save': values.FN_NATIVE(([key, value]) => {
 			utils.assertString(key);
 			miLocalStorage.setItem(`aiscript:${opts.storageKey}:${key.value}`, JSON.stringify(utils.valToJs(value)));
diff --git a/packages/frontend/src/scripts/api.ts b/packages/frontend/src/scripts/api.ts
index 9259c8801..080977e5e 100644
--- a/packages/frontend/src/scripts/api.ts
+++ b/packages/frontend/src/scripts/api.ts
@@ -11,6 +11,7 @@ export const pendingApiRequestsCount = ref(0);
 
 // Implements Misskey.api.ApiClient.request
 export function api<E extends keyof Misskey.Endpoints, P extends Misskey.Endpoints[E]['req']>(endpoint: E, data: P = {} as any, token?: string | null | undefined, signal?: AbortSignal): Promise<Misskey.Endpoints[E]['res']> {
+	if (endpoint.includes('://')) throw new Error('invalid endpoint');
 	pendingApiRequestsCount.value++;
 
 	const onFinally = () => {
@@ -23,7 +24,50 @@ export function api<E extends keyof Misskey.Endpoints, P extends Misskey.Endpoin
 		if (token !== undefined) (data as any).i = token;
 
 		// Send request
-		window.fetch(endpoint.indexOf('://') > -1 ? endpoint : `${apiUrl}/${endpoint}`, {
+		window.fetch(`${apiUrl}/${endpoint}`, {
+			method: 'POST',
+			body: JSON.stringify(data),
+			credentials: 'omit',
+			cache: 'no-cache',
+			headers: {
+				'Content-Type': 'application/json',
+			},
+			signal,
+		}).then(async (res) => {
+			const body = res.status === 204 ? null : await res.json();
+
+			if (res.status === 200) {
+				resolve(body);
+			} else if (res.status === 204) {
+				resolve();
+			} else {
+				reject(body.error);
+			}
+		}).catch(reject);
+	});
+
+	promise.then(onFinally, onFinally);
+
+	return promise;
+}
+
+export function apiExternal<E extends keyof Misskey.Endpoints, P extends Misskey.Endpoints[E]['req']>(hostUrl: string, endpoint: E, data: P = {} as any, token?: string | null | undefined, signal?: AbortSignal): Promise<Misskey.Endpoints[E]['res']> {
+	if (!/^https?:\/\//.test(hostUrl)) throw new Error('invalid host name');
+	if (endpoint.includes('://')) throw new Error('invalid endpoint');
+	pendingApiRequestsCount.value++;
+
+	const onFinally = () => {
+		pendingApiRequestsCount.value--;
+	};
+
+	const promise = new Promise<Misskey.Endpoints[E]['res'] | void>((resolve, reject) => {
+		// Append a credential
+		(data as any).i = token;
+
+		const fullUrl = (hostUrl.slice(-1) === '/' ? hostUrl.slice(0, -1) : hostUrl)
+				+ '/api/' + (endpoint.slice(0, 1) === '/' ? endpoint.slice(1) : endpoint);
+		// Send request
+		window.fetch(fullUrl, {
 			method: 'POST',
 			body: JSON.stringify(data),
 			credentials: 'omit',