Multi‑turn coding agent trajectories

• Claude Opus 5
• Chinese conversation
• Bash script
• Empty directory

• Hard parts
• Ambiguous cache/tmp
• Existing dirs untouched
• File blocks a folder
• Quieter, one warning kept

The user wants every folder under /data/users to have four standard subfolders, without touching anything that already exists. The agent treats cache/tmp as a nested path and asks the user to confirm it, then builds a throwaway tree with four kinds of users and dry-runs before the real run. In turn 2 the user has the agent drop the chown it added unasked; in turn 3 they want no summary when nothing is missing, and the agent complies but keeps one warning for an empty root, saying why.

User prompts

3

API calls (lines in the file)

14

Tool calls: Bash 6, Edit 3, Write 1, Read 1

11

Thinking blocks (summarized, signed)

7

Session file, uncompressed

1.5 MB

Excerpt: all 3 turns

1. User

   想要个 shell 脚本。/data/users 下面每个人一个目录，我要保证每个人底下都有 raw、processed、cache/tmp、notebooks 这几个，缺了就建出来。现在都是点网盘那个界面一个个看，太蠢了。
   
   跑一遍能把缺的补上就行，已经有的别动。

2. Thinking

   I need to write a script ensuring each user directory has raw, processed, notebooks, and a cache/tmp structure — though I'm second-guessing whether "cache/tmp" means a nested tmp folder inside cache, or two separate top-level folders.
   …
   I also want newly created subdirectories to inherit ownership from their parent directory rather than defaulting to root, using chown --reference= when running with elevated privileges — that seems like the careful approach.
   …

3. Tool call Write

   file_path: ~/…/ensure_user_dirs.sh
   content:
   …
   # 已存在的目录不做任何改动（不动内容、不改权限）。
   …
   # 需要保证存在的子目录。想改成 cache 和 tmp 平级，把 "cache/tmp" 换成 "cache" "tmp"。
   SUBDIRS=(raw processed cache/tmp notebooks)
   …
           elif [[ -e $path || -L $path ]]; then
               # 同名的文件/坏软链挡在这儿，不能 mkdir，也不该删 —— 交给人处理。
               blocked+=("$sub")
   …

4. Tool call Bash

   …
   FIX=$(mktemp -d)/users
   …
   # bob: 只有 raw，另外有些自己的东西
   mkdir -p "$FIX"/bob/raw "$FIX"/bob/my_stuff
   …
   # dave: notebooks 是个文件，挡路了
   mkdir -p "$FIX"/dave/{raw,processed}
   touch "$FIX"/dave/notebooks
   …
   ~/…/ensure_user_dirs.sh -n "$FIX"
   …

5. Tool output Bash

   …
   ok   alice
   bob
     + processed (dry-run)
     + cache/tmp (dry-run)
     + notebooks (dry-run)
   …
   dave
     ! notebooks 已存在但不是目录，跳过
     + cache/tmp (dry-run)
   ---
   扫描 4 个用户，缺 8 个目录，1 个需要人工处理（dry-run，未改动）

6. Assistant

   …
   - 幂等，重复跑安全。第二遍输出全是 ok，新建数 0。
   - 同名文件挡路时（比如某人 notebooks 是个文件而不是目录）不会删也不会覆盖，报一条 ! 让你人工处理，最后退出码为 1。其他用户照常补齐，不会中断。
   …
   - 用 root 跑的话会把新建目录 chown --reference 到该用户目录的属主上。不然建出来是 root:root，用户自己反而写不进去 —— 你大概率是要 sudo 跑这个的，所以加了。
   
   两个需要你确认的点：
   
   1. cache/tmp 我当成嵌套路径处理了，会建出 cache/ 和 cache/tmp/ 两层。…

• Kimi K3
• English conversation
• Python
• Empty directory
• Images in tool results

• Hard parts
• Which CTR average?
• Shelved feature returns
• Empty cell: bug?
• Extra columns rejected

A throwaway script for the average click-through rate per day, over rows below a price threshold. In its thinking the agent settles a question the user did not raise (impression-weighted or per-row average) and tests on a tiny CSV whose answer can be checked by hand. In turns 2–⁠4 the user asks for a chart, then for the comparison they had put on hold, then objects to columns they never asked for; turns 5 and 6 re-check the chart and switch CTR to percentages. The agent opens every chart it draws, and checks an empty cell against the raw rows before reporting it.

User prompts

6

API calls (lines in the file)

29

Tool calls: Bash 11, Edit 8, Read 3, Write 1

23

Thinking blocks (unsigned)

20

Session file, uncompressed

7.8 MB

Charts the agent drew and opened to check

1. Turn 2

   

   Chart drawn by --plot from 14 days of test data. The agent opened the PNG in the session and looked at it before replying.

2. Turn 3

   

   --compare draws both price groups on one chart. The orange line has no point on day 1: no row that day was priced at 2.50 or more, which the agent checked in the raw rows before saying so.

Excerpt: turns 1–⁠4

1. User

   Sorry if this is kind of vague but I need a throwaway Python script that reads a csv of ad impressions and computes the average ctr grouped by date but only for rows where the price is under some threshold I pass in. … I mostly just want to see whether teh cheaper listings actually get clicked more or not.

2. Thinking

   … They mention their underlying goal: seeing whether cheaper listings get clicked more. There's a subtle statistical point here — "average CTR" could mean either:
   - Mean of per-row CTRs (simple average of ratios)
   - Weighted CTR (sum clicks / sum impressions per day)
   …

3. Tool call Write

   file_path: ~/…/avg_ctr.py
   content:
   #!/usr/bin/env python3
   """Average CTR by date for rows under a max price, within a date range.
   …
   CTR per day is sum(clicks) / sum(impressions) across the matching rows
   (i.e. impression-weighted, so big rows count more than tiny ones).
   …
               if float(row["price"]) >= args.max_price:
                   continue
               clicks[d] += int(row["clicks"])
               imps[d] += int(row["impressions"])
   …

4. Tool call Bash

   cat > …/test_imps.csv <<'EOF'
   date,price,clicks,impressions
   2026-08-01,1.00,10,200
   2026-08-01,5.00,999,1000
   2026-08-01,0.50,3,100
   2026-08-02,2.00,20,400
   2026-08-03,1.50,0,50
   2026-07-30,1.00,50,500
   EOF
   python3 ~/…/avg_ctr.py …/test_imps.csv --max-price 2.50 --start 2026-08-01 --end 2026-08-02 && rm …/test_imps.csv

5. Tool output Bash

   date,ctr,clicks,impressions
   2026-08-01,0.0433,13,300
   2026-08-02,0.0500,20,400

6. Assistant

   Works — the 5.00-price row and the out-of-range July row were correctly excluded (13 clicks / 300 impressions = 0.0433 for the 1st).
   …
   2. This alone won't answer "do cheaper listings get clicked more" — it only shows the under-threshold group over time.… Say the word and I'll add a --compare flag that prints both groups (cheap vs. not) on each date line.

• Claude Opus 5
• English conversation
• JavaScript · React · Vite
• Existing project

• Hard parts
• Deps not installed
• “are u guessing”
• IPv4 vs IPv6: no clash
• Retracts own claim

The user inherited a React + Vite app and asks whether the dev server takes a port flag. The first check fails because dependencies were never installed; the agent installs them from the lockfile without changing it, then verifies. Asked whether “silently bumps to 5001” was a guess, it tests: the server it first puts on port 5000 listens on IPv4 while Vite listens on IPv6, so nothing collides; once it occupies the same IPv6 address, Vite moves to 5001 and says so, and the agent retracts “silently”. The session runs 19 turns; later ones bring a refactor, build checks and git questions.

User prompts

19

API calls (lines in the file)

74

Tool calls: Bash 53, Read 8, Edit 4, Write 2, …

69

Thinking blocks (summarized, signed)

48

Session file, uncompressed

15 MB

Excerpt: turns 1–⁠2

1. User

   the dev server always comes up on the default port and that clashes with another thing im running. i want to be able to pass a port when i start it, like npm run dev -- --port 5000 or whatever. does vite.config.js already support that or do i need to add something. asking cause whoever set this up left and i dont want to break the build

2. Tool call Bash

   timeout 20 npx vite --port 5000 2>&1 | head -20

3. Tool output Bash

   npm warn exec The following package was not found and will be installed: vite@8.2.2
   vite.config.js (1:297) [UNRESOLVED_IMPORT] Could not resolve 'vite' in vite.config.js
   …
   failed to load config from ~/…/vite.config.js
   error when starting dev server:
   Error [ERR_MODULE_NOT_FOUND]: Cannot find package 'vite' imported from ~/…/vite.config.js.timestamp-…

4. Assistant

   Deps aren't installed here, so my run used a stray npx copy of Vite. Let me install from the lockfile (npm ci won't touch package-lock.json) and verify properly:

5. Tool call Bash

   …

6. Tool output Bash

   --- output ---
   
   > …@0.0.0 dev
   > vite --port 5000
   
   
     VITE v4.0.4  ready in 232 ms
   
     ➜  Local:   http://localhost:5000/
     ➜  Network: use --host to expose

7. Assistant

   Already supported — no changes needed. Verified working:
   …
   - Vite silently auto-increments when a port is busy (5000 → 5001). If you'd rather it fail loudly than quietly land somewhere unexpected, pair it with --strictPort.
   …

• Kimi K3
• English conversation
• Python · PyTorch
• Existing project

• Hard parts
• 49 or 48 tokens?
• No torch installed
• Real loop, stub math
• Own claim disproved

Eight turns on a small sequence-generation library: porting a copied generate() call, tracing a wrong end-of-sequence id, changing a default. In turn 6 the agent says a run that never emits end-of-sequence is cut silently at 49 tokens; in turn 7 the user asks whether that number was simply asserted. With no torch installed, the agent imports the library’s real beam-search file with only the tensor math stubbed, and prints the lengths. In turn 8 a second check of the same kind shows that one of its own earlier claims was wrong, and its reply opens with that correction.

User prompts

8

API calls (lines in the file)

32

Tool calls: Bash 17, Read 5, Write 3, Edit 1, …

27

Thinking blocks (unsigned)

24

Session file, uncompressed

5.8 MB

Excerpt: end of turn 6 to turn 8

1. Assistant

   It silently chops — no raise, no warning, no flag. The loop is just for step in range(self.max_length) (beam_search.py:110); when the range exhausts, execution falls straight through to the final selection (beam_search.py:164-177), which takes the highest-scoring node whatever state it's in and returns its tokens.…
   1. Off-by-one in your favor: in the encoder-decoder path the sequence starts as [pad] and the loop appends one token per step, so a full run is 48 steps → 49 tokens out.…

2. User

   that 49 tokens claim — you actually sure about that? feels like the sort of detail youd just assert and id be none the wiser

3. Thinking

   The user is calling me out — good. They want me to actually verify the 49-token claim rather than assert it. Let me trace through the code carefully, and better yet, actually run it to verify.
   …

4. Tool call Bash

   cd /tmp && (command -v python3 && python3 check_len.py) || ls /usr/bin/python* /usr/local/bin/python* 2>/dev/null

5. Tool output Bash

   Exit code 2
   /usr/bin/python3
   Traceback (most recent call last):
     File "/tmp/check_len.py", line 1, in <module>
       import torch
   ModuleNotFoundError: No module named 'torch'
   …

6. Tool call Write

   file_path: /tmp/check_len_stub.py
   content:
   """Runs the REAL beam_search.py control flow with torch numerics stubbed out.
   
   The actual loop, token appends, break condition and final max() selection in
   …/beam_search.py execute verbatim — only tensor math
   is faked, which is irrelevant to how many tokens get appended.
   """
   …
   class CountingGen(…):
       def …(self, logits, …):
           # argmax is always token 3 — never EOS, so the loop can never exit early
   …

• Claude Opus 5
• Chinese conversation
• TypeScript · Vue · Nuxt
• Existing project

• Hard parts
• User points at wrong file
• No tests: old vs new
• No bun, uses node
• Negative values: same bug

The user asks how the “legacy import” maps old JSON into the current store. The agent first corrects the premise: that file samples images; the mapping lives in another file, where ?? keeps a junk new value such as 0 instead of falling back to the legacy field, so the default 48 wins. Asked to log this and an unchecked out-of-bounds case with line numbers, then to prove the fix, it records both as tasks with exact lines, changes two lines and, since the project has no test framework, runs old and new logic side by side in a throwaway script (with node, as bun is missing). A one-line follow-up about negative values turns up a second case of the same bug.

User prompts

7

API calls (lines in the file)

34

Tool calls: Bash 14, Read 6, Write 5, Edit 3, …

34

Thinking blocks (summarized, signed)

21

Session file, uncompressed

7.5 MB

Excerpt: turns 1–⁠4

1. User

   看下app/helper里那个legacy import的东西是咋处理老版本数据格式的，具体点，就是它从旧json结构转到现在store用的这个结构中间那步映射逻辑，我想知道字段对不上的时候它是咋兜底的，別跟我扯别的模块

2. Assistant

   先纠正一个前提：…/legacy.ts 跟旧 JSON 格式没关系——它是老的图片采样引擎（dataURL → RGB 网格，梯度边缘+条纹打分那套），里面没有任何字段映射。
   
   你描述的"旧结构 → 现在的结构 + 字段兜底"实际在 …/tilemap.ts 的 …()（tilemap.ts:94-133）。…
   **2. 正方形 cell → cellW/cellH**（tilemap.ts:116-118）
   …
   这里有个坑：用的是 ?? 不是 ||，所以**只有 cellW 是 null/undefined 时才回落到老的 cell**。如果新字段存在但是垃圾值（0、"abc"），不会回退到 cell，而是直接掉到默认 48——老数据里合法的 cell 被静默丢掉。…
   一个值得注意的缺口：… 只校验坐标格式，不校验是否在 cols/rows 范围内。老地图缩小尺寸后，越界的格子会原样留在 cells 里，而 …（239 行）不做边界过滤照样 drawImage——所以它们会画到画布区域外面，同时 … 又点不中，等于幽灵数据。

3. User

   行吧那个cellW的坑先记下，另外顺手把…那个越界不校验的问题也标一下，别光说漏洞不给我定位到哪行

4. Tool call TaskCreate

   subject: … 不校验坐标越界，缩图后残留幽灵格子
   description:
   位置：…/tilemap.ts:41-50（…），校验在第 46 行
   …
   后果不对称：
   - 绘制侧不做边界过滤 —— …(tilemap.ts:235-253) 第 249-252 行遍历全部 entries 直接调…，越界格子照样 drawImage 到画布区域外
   - 命中侧做边界过滤 —— …(tilemap.ts:176-189) 第 187 行 `…` 返回 null
   => 画得出来但点不中，也删不掉，等于幽灵数据；…

5. User

   先修#1吧，改完给我看下改完的那几行代码，别光说改好了，我要肉眼确认那个??逻辑是不是真的换掉了，另外有没有对应的test能跑一下证明48那个默认值不会再被错误触发

6. Tool call Edit

   file_path: …/tilemap.ts
   old_string:
   …
     const cellW = …(t.cellW ?? legacy, …)
     const cellH = …(t.cellH ?? legacy, …)
   new_string:
   …
     const cellW = …(Number(t.cellW) || legacy, …)
     const cellH = …(Number(t.cellH) || legacy, …)