Claude Code 2.1.206

你把任務丟給背景代理（background agent，讓 Claude 在背景幫你跑活、你先去忙別的的功能）之後，現在可以放心走開了。以前它有一堆怪毛病：在 macOS 上開啟或切換要莫名卡 15 到 20 秒、內部通行證（session token，系統認人用的臨時憑證）過期後整隻永遠叫不醒、回到列表畫面還會偷偷把跑到一半的子任務砍掉從頭重來；這批毛病一次修完，斷線還會自己接回來。就像洗衣店以前偶爾弄丟衣服、或把洗到一半的整批重洗，現在每件衣服的進度都記得牢牢的，你隨時回來拿都對得上。

覺得 Claude Code 哪裡怪怪的，現在打一句 /doctor 就能做全身健檢，而且它不只診斷、還會動手修；順口的別名 /checkup 也通。健檢項目也變多：會建議你精簡塞太肥的 CLAUDE.md（專案說明檔，Claude 每次開工都要先讀的備忘錄）——凡是 Claude 自己看程式碼就推得出來的內容都可以刪掉省空間；用 Homebrew 裝的人，更新檢查也改成對正確的更新頻道。就像健檢中心從「只印報告」升級成「當場幫你拔智齒」。

Windows 使用者這條要看：以前清理工作樹（worktree，讓同一個專案多開幾份平行工作副本的 git 功能）時，如果裡面藏著 NTFS 目錄捷徑（junction，Windows 上把一個資料夾指向另一個位置的分身），刪除會順著捷徑刪到工作樹外面的真檔案；現在修好了，刪除只動工作樹自己的東西。就像拆違建時以前會順著水管拆到隔壁鄰居家，現在確實只拆自己這一戶。

有裝 MCP 伺服器（Model Context Protocol，讓 Claude 外接其他工具服務的插座標準）的人，這輪有兩個修復。一是你在設定裡寫的單一伺服器逾時秒數（request_timeout_ms）以前會被無視、新對話一律用預設 60 秒就砍線，跑比較久的工具老是被斷頭，現在真的照你設的來；二是走 OAuth 登入（把登入委託給原服務認證的機制）的伺服器，以前只要一次換證失敗就逼你手動重新登入，現在小失誤會自己重試接上。就像延長線以前標示耐重 10 公斤、實際 6 公斤就跳電，現在標多少就耐多少。

打 /model 挑模型時，價格標籤不再張冠李戴。以前清單有時會把 A 模型的單價印在 B 模型那一列，害你以為換了個便宜的、其實更貴；順帶也不再對「根本不照官方定價收費」的第三方供應商硬印官方牌價。就像菜單以前會把牛排的價錢印在義大利麵旁邊，現在每道菜對準自己的標價，代售的菜也不再亂掛別家的價目。

Once you hand a job to a background agent (a feature that lets Claude keep working on a task while you go do something else), you can now actually walk away. It used to have a pile of quirks: opening or switching sessions on macOS could stall for 15–20 seconds, an expired internal session token (the temporary pass the system uses to recognize you) could leave a session permanently unresponsive, and returning to the list view could silently kill half-finished subagents and restart them from scratch. All of these are fixed, and dropped sessions now reconnect on their own. It's like a laundry service that used to occasionally lose your clothes or rewash a half-done load; now every item's progress is tracked, and whenever you come back, it all checks out.

When Claude Code feels off, one /doctor now runs a full checkup — and it doesn't just diagnose, it can fix what it finds; /checkup works as an alias. The checkup also covers more ground: it can propose trimming an overweight CLAUDE.md (the project memo Claude reads before every work session) by cutting anything Claude could figure out from the code itself, and Homebrew installs now get their update check compared against the right release channel. It's like a health clinic upgrading from "here's your report" to "let's pull that wisdom tooth right now."

Windows users, this one's for you: removing a worktree (a git feature that gives one project several parallel working copies) used to follow any NTFS junction or directory symlink (a Windows shortcut that points a folder at another location) hiding inside it and delete real files outside the worktree; that's fixed, and removal now touches only the worktree's own files. Like a demolition crew that used to follow the plumbing into the neighbor's house — now it strictly tears down only your unit.

If you run MCP servers (Model Context Protocol, the socket standard that lets Claude plug into outside tools), two fixes this round. First, the per-server timeout you set (request_timeout_ms) used to be ignored — fresh sessions cut every call off at the default 60 seconds, beheading long-running tools; it now honors your setting. Second, OAuth-based servers (which delegate sign-in to the original service) used to demand a full manual re-login after a single failed token refresh; small hiccups now retry and reconnect on their own. Like a power strip that claimed a 10 kg rating but tripped at 6 — now it holds exactly what the label says.

When you open /model to pick a model, price tags no longer land on the wrong row. The list could print one model's price next to another model's name, letting you "switch to something cheaper" that wasn't; it also stops quoting first-party list prices for third-party providers that don't bill by them at all. Like a menu that used to print the steak's price next to the pasta — every dish now wears its own tag, and consignment dishes stop borrowing another shop's price list.