Claude Opus 5.5 (effort default (no --effort flag) · thinking on) on Write release notes from a conventional-commit log (breaking changes, reverts, cherry-pick duplicates, semver bump)

AClaude Opus 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: $0.11
Wall time: 15s
Human step-ins: 0
Outcome: Pass

Compare with other models on this task →

Exact prompt

# Task: write the release notes `commits.txt` lists every commit since the last release, newest first, after two header lines (`previous:` = last released version, `release_date:`). Each commit is one line `<hash> <subject>`; indented lines after it are that commit's body. Write `RELEASE_NOTES.md` in this directory following these rules exactly. You may write it by hand or with a script. No network. 1. Conventional subjects look like `<type>(<scope>)!: <description> (#<PR>)`; the `(<scope>)`, the `!` and the ` (#<PR>)` suffix are each optional. A subject that does not have this shape (merge commits, "WIP ...") is excluded. 2. `feat` goes to **Features**, `fix` to **Fixes**, `perf` to **Performance**. All other types (`chore`, `docs`, `test`, `ci`, `style`, `refactor`, `build`, ...) are excluded, unless the commit is breaking. 3. A commit is breaking if it has `!` before the `:` or a body line starting with `BREAKING CHANGE: `. Breaking commits of ANY type are listed only under **Breaking changes** (not also in their type section). Their bullet text is the text after `BREAKING CHANGE: ` if there is such a line, otherwise the description. 4. A `revert:` commit whose body contains `This reverts commit <hash>.` removes itself and the commit with that hash. If that hash is not in the list, only the revert commit itself is excluded. Revert commits never appear in the notes. 5. If the same PR number appears on more than one included commit (cherry-picks), list it once, using the commit that appears first in the file. 6. Bullet format: `- **<scope>:** <text> (#<PR>)` when there is a scope, else `- <text> (#<PR>)`; leave out ` (#<PR>)` when the commit has no PR number. `<text>` is the description (or the breaking text from rule 3) with its first letter upper-cased and any trailing period removed; everything else is kept as written. 7. Inside a section, bullets with a PR number come first, sorted by PR number ascending, then bullets without a PR number in file order. 8. Version: from `previous` vX.Y.Z, bump major (to X+1.0.0) if anything breaking is included, else minor (X.Y+1.0) if any feature is included, else patch (X.Y.Z+1). 9. Layout: the first line is `# v<version> - <release_date>`. Then the non-empty sections in this order, each as a `## ` heading: `## Breaking changes`, `## Features`, `## Fixes`, `## Performance`, each followed by its bullets. The file contains only these heading lines, bullet lines and blank lines. The grader parses `RELEASE_NOTES.md` and compares the title line, the section order and every bullet line exactly (trailing spaces ignored).

Breaking footers on non-feature types, a revert that cancels a feature vs one whose target is absent, a duplicated PR, non-conventional subjects, PR-number ordering and a major bump all have one correct rendering. 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. title_and_version_correct. 2. sections_correct_and_ordered. 3. breaking_bullets_exact. 4. features_bullets_exact. 5. fixes_bullets_exact. 6. performance_bullets_exact. 7. no_extra_lines: only headings, bullets and blank lines.

Setup notes: Use Case Scout batch 7 case g07-release-notes-from-commits (offline fixture). Prepared with batch7/prepare.sh; hidden key/tests kept outside the agent's work dir. Prompt = TASK.md verbatim. Scored with the scout's 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-opus-5.5: $0.105435. 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: $0.11
Wall time: 15s
Human step-ins: 0
Turns: 3

Model usage
Model	Input tok	Output tok	Cost
AClaude Opus 5.5anthropic/claude-opus-5.5effort default (no --effort flag) · thinking on	58,288	1,448	$0.11

Reproduce this run

Use the use case prompt on the use case page.
Same setup: Claude Opus 5.5 (anthropic/claude-opus-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. title_and_version_correct. 2. sections_correct_and_ordered. 3. breaking_bullets_exact. 4. features_bullets_exact. 5. fixes_bullets_exact. 6. performance_bullets_exact. 7. no_extra_lines: only headings, bullets and blank lines.
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": 13986,
  "stop_reason": "end_turn",
  "session_id": "[REDACTED]",
  "total_cost_usd": 0.105435,
  "usage": {
   "input_tokens": 6,
   "cache_creation_input_tokens": 8307,
   "cache_read_input_tokens": 49975,
   "output_tokens": 1448,
   "output_tokens_details": {
    "thinking_tokens": 444
   },
   "server_tool_use": {
    "web_search_requests": 0,
    "web_fetch_requests": 0
   },
   "service_tier": "standard",
   "cache_creation": {
    "ephemeral_1h_input_tokens": 8307,
    "ephemeral_5m_input_tokens": 0
   },
   "inference_geo": "global",
   "iterations": [
    {
     "input_tokens": 2,
     "output_tokens": 443,
     "cache_read_input_tokens": 19435,
     "cache_creation_input_tokens": 1018,
     "cache_creation": {
      "ephemeral_5m_input_tokens": 0,
      "ephemeral_1h_input_tokens": 1018
     },
     "type": "message"
    }
   ],
   "speed": "standard",
   "fallback_credit": null
  },
  "modelUsage": {
   "claude-opus-5-5": {
    "inputTokens": 6,
    "outputTokens": 1448,
    "cacheReadInputTokens": 49975,
    "cacheCreationInputTokens": 8307,
    "webSearchRequests": 0,
    "costUSD": 0.105435,
    "contextWindow": 1000000,
    "maxOutputTokens": 128000,
    "thinkingTokens": 444,
    "canonicalModel": "claude-opus-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": 3,
  "subtype": "success",
  "api_error_status": null,
  "result": "I wrote `RELEASE_NOTES.md` by hand, without a script. The new version is **v3.0.0** (up from v2.3.1) because three breaking changes are included. I haven't run the grader against it.\n\nThe commits that needed a judgement call:\n- **Reverts:** The dark mode toggle (#420) and the revert that removes it are both left out. The revert of `9999999` names a commit that isn't in the list, so only the revert itself is dropped and the progress bar fix (#409) stays.\n- **Breaking changes:** Three commits are listed only under Breaking changes, using their `BREAKING CHANGE:` text where they have one:\n  - the `refactor(core)!` Python 3.9 change (#424), which would otherwise have been excluded as a refactor\n  - `feat(api)!` (#419)\n  - `fix(auth)` (#411), whose body has a `BREAKING CHANGE:` line\n- **Duplicate PR:** #422 appears twice and is listed once, using the commit nearer the top of the file.\n- **Excluded:** The merge commit, the WIP commit, and the chore, docs, test, ci, style and build commits.\n\nThe file has 3 breaking changes, 4 features, 7 fixes and 3 performance items. Within each section, bullets are sorted by PR number, and the ones without a PR number come last.",
  "ttft_ms": 1907,
  "type": "result",
  "duration_ms": 14264,
  "uuid": "[REDACTED]",
  "ttft_stream_ms": 1074,
  "time_to_request_ms": 224,
  "first_content_frame_ms": 1074,
  "queued_turn_count": 0,
  "result_index": 0
 }
]