diff --git a/eagle-twitter-tags.user.js b/eagle-twitter-tags.user.js
new file mode 100644
index 0000000..0e94708
--- /dev/null
+++ b/eagle-twitter-tags.user.js
@@ -0,0 +1,135 @@
+// ==UserScript==
+// @name                Eagle 自動 Twitter 標籤
+// @version             1.0.0
+// @description         Eagle 自動 Twitter 標籤
+// @author              Shiaupiau
+// @namespace           https://github.com/stu43005
+// @match               *://twitter.com/*
+// @match               *://x.com/*
+// @run-at              document-end
+// @noframes
+// @grant               GM_xmlhttpRequest
+// ==/UserScript==
+// @ts-check
+/// <reference types="tampermonkey" />
+"use strict";
+
+class EagleApi {
+    // Eagle API URL
+    static EAGLE_SERVER_URL = "http://localhost:41595";
+    static TAG_LIST_API_URL = `${this.EAGLE_SERVER_URL}/api/tag/list`;
+
+    /** @type {Promise<EagleTagItem[]> | null} */
+    static tagListPromise = null;
+    /** @type {string[] | null} */
+    static tags = null;
+
+    /**
+     * @template T
+     * @typedef {Object} EagleApiResult<T>
+     * @prop {string} status
+     * @prop {T} data
+     */
+    /**
+     * @typedef {Object} EagleTagItem
+     * @prop {string} name
+     * @prop {number} imageCount
+     * @prop {string[]} groups
+     * @prop {string} pinyin
+     */
+
+    /**
+     * fetch tag list
+     * @returns {Promise<EagleTagItem[]>}
+     */
+    static fetchTagList() {
+        return new Promise((resolve, reject) => {
+            GM_xmlhttpRequest({
+                url: this.TAG_LIST_API_URL,
+                method: "GET",
+                onload: (response) => {
+                    try {
+                        /** @type {EagleApiResult<EagleTagItem[]>} */
+                        const result = JSON.parse(response.response);
+                        if (result.status === "success" && result.data) {
+                            console.log(`Eagle tag list:`, result.data);
+                            resolve(result.data);
+                        } else {
+                            reject(result);
+                        }
+                    } catch (err) {
+                        reject(err);
+                    }
+                },
+            });
+        });
+    }
+
+    static async getTags() {
+        try {
+            if (!this.tags) {
+                this.tagListPromise ??= EagleApi.fetchTagList();
+                this.tags = (await this.tagListPromise).map((item) => item.name);
+            }
+            return this.tags;
+        } catch (error) {
+            this.tagListPromise = null;
+            console.log(`Unable to fetch Eagle tag list`);
+            throw error;
+        }
+    }
+}
+
+/**
+ * @param {Element} article
+ */
+async function eagleAttributes(article) {
+    try {
+        const tweetPhotos = Array.from(
+            article.querySelectorAll(`[data-testid="tweetPhoto"] img`)
+        ).filter((img) => !img.hasAttribute("eagle-tags"));
+        const hashtags = Array.from(article.querySelectorAll(`a[href^="/hashtag/"]`))
+            .map((element) => element.textContent?.replace(/^#/, ""))
+            .filter((text) => text !== undefined);
+        if (tweetPhotos.length > 0 && hashtags.length > 0) {
+            const eagleTags = await EagleApi.getTags();
+            const addTags = eagleTags.filter((tag) =>
+                hashtags.find((hashtag) => tag.toLowerCase() === hashtag.toLowerCase())
+            );
+
+            for (const img of tweetPhotos) {
+                img.setAttribute("eagle-tags", addTags.join(","));
+            }
+        }
+    } catch (error) {
+        console.log(error);
+    }
+}
+
+const ARTICLE_SELECTOR = `article[data-testid="tweet"]`;
+
+const observer = new MutationObserver((mutationList) => {
+    for (const mutation of mutationList) {
+        for (const addedNode of mutation.addedNodes) {
+            if (addedNode instanceof Element) {
+                if (addedNode.matches(ARTICLE_SELECTOR)) {
+                    eagleAttributes(addedNode);
+                } else {
+                    const closestArticle = addedNode.closest(ARTICLE_SELECTOR);
+                    if (closestArticle) {
+                        eagleAttributes(closestArticle);
+                    } else {
+                        const articles = Array.from(addedNode.querySelectorAll(ARTICLE_SELECTOR));
+                        for (const article of articles) {
+                            eagleAttributes(article);
+                        }
+                    }
+                }
+            }
+        }
+    }
+});
+observer.observe(document.body, {
+    childList: true,
+    subtree: true,
+});