Here’s a WordPress post_tag description for “旅行社” (旅行社) in Traditional Chinese, keeping in mind that concise and helpful descriptions are best for tags:

**Description (Traditional Chinese):**

> 涵蓋所有旅遊相關的文章，包括行程規劃、套裝行程、旅行社介紹、優惠活動及旅遊資訊分享。方便快速找到與旅行社相關的資訊，為您的旅程做好準備！
>
> (Hán gài suǒ yǒu lǚyóu xiāng guān de wénzhāng, bāo kuò xíngchéng guīhuà, tào zhuāng xíngchéng, lǚxíngshè jièshào, yōuhuì huódòng jí lǚyóu zīxùn fēnxiǎng. Fāngbiàn kuàisù zhǎodào yǔ lǚxíngshè xiāng guān de zīxùn, wèi nín de lǚchéng zuò hǎo zhǔnbèi!)

**Explanation of the Description:**

* **Concise & Clear:** The description is short and gets straight to the point.
* **Comprehensive:** It covers a range of topics commonly associated with travel agencies, including itinerary planning (行程規劃), package tours (套裝行程), agency introductions (旅行社介紹), promotions (優惠活動), and general travel information (旅游资讯分享).
* **User-Centric:** It focuses on the benefit for the reader: making it easy to find information related to travel agencies for planning their trips. (方便快速找到……).
* **Action-Oriented (Subtle):** It hints at preparedness, encouraging readers to use the information for trip planning. (為您的旅程做好準備！)
* **Includes Pinyin (in the comment):** Includes Pinyin for easier accessibility and understanding for users.

**Why this is a good description:**

* **Relevance:** Directly relates to the tag “旅行社” and its associated content.
* **Search Engine Optimization (SEO):** Uses relevant keywords like “行程規劃” (itinerary planning), “套裝行程” (package tour), and “優惠活動” (promotion), which people might search for.
* **User Experience (UX):** Helps users quickly understand what kind of content falls under this tag and encourages them to explore.
* **Focus:** Does not bloat the description with unnecessary information.

This description should effectively serve as a guide for your website visitors when they encounter the “旅行社” tag. Remember to tailor specific details in any actual post for your reader audience and website needs.