diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..7621a21
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,13 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## What this is
+
+A personal notes repo documenting Homebrew-installed CLI tools. No code, no build, no tests — just markdown. Each tool gets one file at the repo root (e.g. `witr.md`, `README.md` for WhatCable).
+
+## Conventions
+
+- **Language**: docs are written in Traditional Chinese (繁體中文). Command names, flags, and code stay in English.
+- **One file per tool**, named after the tool. Structure follows the existing files: title + one-line purpose + version, upstream/project link, install (`brew install ...`), then usage / options tables / examples.
+- Options are documented as markdown tables (`| 旗標 | 說明 |`). Pro/licensed features get their own sub-table.
diff --git a/frogmouth.md b/frogmouth.md
new file mode 100644
index 0000000..8cd2f5f
--- /dev/null
+++ b/frogmouth.md
@@ -0,0 +1,64 @@
+# Frogmouth CLI 文件
+
+在終端機瀏覽 Markdown 的 TUI 工具,支援本機檔案與遠端 URL、書籤、瀏覽紀錄、目錄索引。版本 v0.9.1。
+
+專案:<https://github.com/textualize/frogmouth>
+
+## 安裝
+
+沒有 brew formula,用 pipx 安裝(官方建議方式):
+
+```sh
+pipx install frogmouth
+```
+
+> 注意:frogmouth 0.9.2 相依的舊 `httpx`/`httpcore` 在 Python 3.14 下會崩潰。若 pipx 抓到 3.14,裝完後升級這兩個套件即可修正(pip 會警告版本超出 pin,實測可正常執行):
+>
+> ```sh
+> pipx runpip frogmouth install -U httpx httpcore
+> ```
+
+## 基本用法
+
+```sh
+frogmouth                      # 開啟空白瀏覽器
+frogmouth README.md            # 開本機 Markdown
+frogmouth https://…/file.md    # 開遠端 Markdown
+```
+
+## Omnibox 指令
+
+按 `/` 或 `:` 叫出 omnibox,輸入位址或以下指令(括號為別名):
+
+| 指令 | 別名 | 說明 |
+|------|------|------|
+| `<路徑或 URL>` | | 開啟本機檔案或遠端 Markdown |
+| `contents` | `c`, `toc` | 顯示目前文件的目錄索引 |
+| `bookmarks` | | 開啟書籤清單 |
+| `history` | `h` | 開啟瀏覽紀錄 |
+| `local` | `l` | 瀏覽本機檔案 |
+| `chdir` | `cd` | 切換本機檔案瀏覽目錄 |
+| `changelog` | `cl` | 顯示 frogmouth 的變更紀錄 |
+| `about` | `a` | 關於 |
+| `help` | `?` | 說明 |
+| `quit` | `q` | 結束 |
+
+## 按鍵
+
+| 按鍵 | 說明 |
+|------|------|
+| `/`, `:` | 叫出 omnibox |
+| `Ctrl+N` | 開啟/切換左側導覽面板(目錄、書籤、紀錄) |
+| `\` | 導覽面板靠左/靠右切換 |
+| `F1` | 說明 |
+| `F2` | 關於 |
+| `Ctrl+Q` | 結束 |
+
+在書籤或紀錄清單中:`Delete` 刪除項目、`r` 重新命名書籤、`Backspace` 清空紀錄。
+
+## 範例
+
+```sh
+frogmouth witr.md              # 在終端機閱讀本機筆記
+frogmouth https://raw.githubusercontent.com/textualize/frogmouth/main/README.md
+```