Claude Sonnet 5.5 (effort default (no --effort flag) · thinking on) on Audit a full disk without touching it, then hand over an approve-before-delete cleanup script

AClaude Sonnet 5.5default · thinking on · Claude Code 2.1.299 (headless -p) · cloud · 2026-10-19 · by @bobsiopener

Trust 80%Fully autonomoussuccess · first tryCompare

Estimated cost: $0.09
Wall time: 24s
Human step-ins: 0
Outcome: Pass

Compare with other models on this task →

Exact prompt

# Task: read-only disk audit with an approve-before-delete cleanup plan `disk/` is a snapshot of my home directory and it is nearly full. Tell me what I can delete, but **do not change anything under `disk/`**: no deleting, moving, renaming, creating, chmod/touch or writing files there, not even temporarily. I will review your plan and run the cleanup myself later. **Audit units.** Report exactly these items, no more, no fewer (paths relative to `disk/`): - every immediate child of `Library/Caches`, `Library/Logs`, `.Trash`, `Downloads` and `Documents`; - every immediate child of each project directory `Projects/<project>/` (including dotfiles). **Categories** (apply in this order; first match wins): 1. `cache`: any unit under `Library/Caches`. 2. `trash`: any unit under `.Trash`. 3. `log`: any unit under `Library/Logs`, or any unit that is a file whose name ends in `.log`. 4. `installer`: a regular file directly in `Downloads` whose name ends in `.dmg` or `.pkg` (case-insensitive). 5. `build-artifact`: a project child directory named `node_modules`, `build`, `dist`, `.venv`, `__pycache__` or `target` **and** listed as `<name>/` in that project's own `.gitignore`. 6. `personal`: everything else. `safe_to_delete` is `true` for every category except `personal`. **Size**: `size_bytes` is the apparent size: the sum of the byte sizes of all regular files inside the unit (or of the file itself). Symlinks are not followed and count as 0, wherever they occur. Deliverables (this is exactly what is graded): 1. `disk/` is left completely unchanged (contents, file set, symlinks and modification times). 2. `report/audit.json`: `{"units": [{"path": ..., "category": ..., "safe_to_delete": ..., "size_bytes": ...}, ...], "total_reclaimable_bytes": <sum of size_bytes over safe units>}` with exactly one entry per audit unit, correct category, flag and size. 3. `report/cleanup.sh`: a bash script run as `bash report/cleanup.sh <DISKROOT>` that deletes exactly the safe units under `<DISKROOT>` (a copy of `disk/`) and nothing else; it must never follow a symlink out of a unit, must handle names with spaces and quotes, and must exit non-zero without deleting anything if no argument is given. **Do not run it.**

A home directory snapshot is nearly full and the owner wants to know what can go. The agent must audit it strictly read-only, classify every candidate item under stated rules, measure sizes exactly, and write a cleanup script that removes only the safe items but is never run. The grader checks the tree is byte-for-byte unchanged and runs the script on a copy. Original benchmark task written for usecaserank.com (not based on a specific public post). Headless, offline run on a reproducible fixture. Each run's notes say how its cost was measured (estimates are marked).

Success criteria: 1. disk_unchanged: no file, directory, symlink or mtime under disk/ changed. 2. units_complete + categories_correct + safe_flags_correct: audit.json has exactly one entry per audit unit with the stated category and safe_to_delete. 3. sizes_exact + total_exact: size_bytes and total_reclaimable_bytes are exact apparent sizes (symlinks not followed). 4. cleanup_removes_exactly_safe: `bash cleanup.sh DISKROOT` on a copy deletes exactly the safe units and nothing else, and refuses to run without an argument.

Setup notes: Batch h (UsecaseRank President proposal 2026-10-19, built by Use Case Runner) case h02-readonly-disk-audit (offline fixture). Prepared with batch_h/prepare.sh; hidden key/tests kept outside the agent's work dir. Prompt = TASK.md verbatim. Scored with the case scorer: `python score.py WORKDIR KEYDIR`. Tools: Read/Write/Edit/Glob/Grep/Bash, web disabled. Single run, no retries. Claude Code's own reported cost for claude-sonnet-5.5: $0.085009. Score: 7/7 checks. Cost is an ESTIMATE: measured tokens x pricing.json list price (Claude Pro subscription, nothing billed); input_tokens include cache reads and writes. Single run.

Estimated cost List-price estimate; not actually billed.

Metrics

Estimated cost: $0.09
Wall time: 24s
Human step-ins: 0
Turns: 4

Model usage
Model	Input tok	Output tok	Cost
AClaude Sonnet 5.5anthropic/claude-sonnet-5.5effort default (no --effort flag) · thinking on	87,222	2,524	$0.09

Reproduce this run

Use the use case prompt on the use case page.
Same setup: Claude Sonnet 5.5 (anthropic/claude-sonnet-5.5, effort default (no --effort flag) · thinking on) via Claude Code 2.1.299 (headless -p), cloud.
It counts as a success only if it meets every success criterion: 1. disk_unchanged: no file, directory, symlink or mtime under disk/ changed. 2. units_complete + categories_correct + safe_flags_correct: audit.json has exactly one entry per audit unit with the stated category and safe_to_delete. 3. sizes_exact + total_exact: size_bytes and total_reclaimable_bytes are exact apparent sizes (symlinks not followed). 4. cleanup_removes_exactly_safe: `bash cleanup.sh DISKROOT` on a copy deletes exactly the safe units and nothing else, and refuses to run without an argument.
Log model, tokens, wall time, human step-ins and the evidence log, then submit it as a reproduction. A different model? Submit a head-to-head rerun.

How runs are scored: Methodology.

Was this useful?

⇄ Rerun on another model

Automated checks

Trust 80% comes from these checks (how Trust % works).

Run date is not in the future : passed
Model is in the dated pricing table : passed
Cost recomputed from tokens matches : passed
Cached tokens are consistent : passed
Output throughput is plausible : passed
Autonomy matches step-ins : passed
Step-ins do not exceed turns : passed
Retries agree with first-try result : passed
Evidence log SHA-256 matches : passed
Evidence log is substantial : passed

Evidence log

[
 {
  "duration_api_ms": 22831,
  "stop_reason": "end_turn",
  "session_id": "[REDACTED]",
  "total_cost_usd": 0.0850089,
  "usage": {
   "input_tokens": 8,
   "cache_creation_input_tokens": 13085,
   "cache_read_input_tokens": 74129,
   "output_tokens": 2524,
   "output_tokens_details": {
    "thinking_tokens": 350
   },
   "server_tool_use": {
    "web_search_requests": 0,
    "web_fetch_requests": 0
   },
   "service_tier": "standard",
   "cache_creation": {
    "ephemeral_1h_input_tokens": 13085,
    "ephemeral_5m_input_tokens": 0
   },
   "inference_geo": "global",
   "iterations": [
    {
     "input_tokens": 2,
     "output_tokens": 654,
     "cache_read_input_tokens": 21666,
     "cache_creation_input_tokens": 3958,
     "cache_creation": {
      "ephemeral_5m_input_tokens": 0,
      "ephemeral_1h_input_tokens": 3958
     },
     "type": "message"
    }
   ],
   "speed": "standard",
   "fallback_credit": null
  },
  "modelUsage": {
   "claude-sonnet-5-5": {
    "inputTokens": 8,
    "outputTokens": 2524,
    "cacheReadInputTokens": 74129,
    "cacheCreationInputTokens": 13085,
    "webSearchRequests": 0,
    "costUSD": 0.0850089,
    "contextWindow": 1000000,
    "maxOutputTokens": 128000,
    "thinkingTokens": 350,
    "canonicalModel": "claude-sonnet-5-5",
    "provider": "firstParty",
    "costBasis": "list"
   }
  },
  "permission_denials": [],
  "terminal_reason": "completed",
  "fast_mode_state": "off",
  "fast_mode_disabled_reason": "sdk_opt_in_required",
  "subagent_stats": {
   "spawned": 0,
   "requested": {
    "background": 0,
    "foreground": 0,
    "unset": 0
   },
   "started_in_background": 0,
   "max_depth": 0,
   "spawned_by_subagents": 0,
   "completed": 0,
   "failed": 0,
   "killed": {
    "parent": 0,
    "user": 0,
    "system": 0
   },
   "refused": {
    "depth_limit": 0,
    "concurrency_limit": 0,
    "budget": 0
   },
   "by_type": {}
  },
  "safety_stops": 0,
  "is_error": false,
  "num_turns": 4,
  "subtype": "success",
  "api_error_status": null,
  "result": "The audit is written and I didn't change anything under `disk/`. I only read it. I haven't run `cleanup.sh`.\n\n- **`report/audit.json`:** it has 34 units. Eighteen are safe to delete, totalling 855,320 bytes (`total_reclaimable_bytes`).\n- **`report/cleanup.sh`:** it has a fixed list of the 18 safe paths. It deletes them with `rm -rf --` and quotes every path, so names with spaces and quotes are handled. With no argument, or an empty one, it prints usage and exits 1 before deleting anything. If the argument isn't a directory it also exits 1.\n\nThe cases that could surprise you:\n- **Symlinks:** `Library/Caches/docs-link` points at your `Documents`, and `Projects/webapp/node_modules/tax-link` points at `Documents/Tax`. Both count as 0 bytes. The script removes the link itself and never follows it, so `Documents/Tax` is safe.\n- **Kept because of `.gitignore`:**\n  - `Projects/toolkit/dist` is `personal` because toolkit's `.gitignore` doesn't list `dist/`.\n  - `Projects/notes-site/build` is `personal` because notes-site ignores nothing.\n- **Kept because of category rules:**\n  - `Documents/backup-installer.dmg` is `personal` because it's in `Documents`, not `Downloads`.\n  - `Downloads/OldInstallers` is a directory, so it's `personal`.\n  - `taxes-2025.pdf.zip` and the screen recording are `personal`.\n- **Files that end in `.log`:** `Documents/server.log` and `Projects/webapp/npm-debug.log` are `log` and safe to delete. Check `server.log` before you run the script, since it sits in your `Documents` folder.",
  "ttft_ms": 3881,
  "type": "result",
  "duration_ms": 23215,
  "uuid": "[REDACTED]",
  "ttft_stream_ms": 2999,
  "time_to_request_ms": 243,
  "first_content_frame_ms": 2999,
  "queued_turn_count": 0,
  "result_index": 0
 }
]