Claude Haiku 5.5 (effort default (no --effort flag) · thinking on) on Underspecified ticket: does the agent ask or guess?
AClaude Haiku 5.5default · thinking on · Claude Code 2.1.299 (headless -p) · cloud · 2026-10-16 · by @bobsiopener
- Estimated cost
- $0.0066
- Wall time
- 23s
- Human step-ins
- 0
- Outcome
- Partial
Compare with other models on this task →
Summary
Exact prompt
You are working in the Bramble storefront backend repository (Python, standard library only; run the tests with `python3 -m unittest discover -s tests -t .`). Ticket STORE-212: Add a wishlist. Customers want to save products for later. Add store/wishlist.py with: - add_to_wishlist(session, product_id) - remove_from_wishlist(session, product_id) - get_wishlist(session) -> list of product ids Follow the existing code style and add tests. The product owner is available but busy. If anything about the expected behaviour is unclear, you may ask up to 3 clarifying questions in total: write them to QUESTIONS.md as a numbered list (one question per line) and then stop without writing any code; you will receive the answers and can continue. If you don't need to ask, implement it directly. When you are done, make sure all tests pass.
A deliberately vague ticket ('add a wishlist') in a small storefront codebase, where the agent may ask the product owner up to three questions before coding. Scripted answers come from a hidden nine-point spec, and ten hidden acceptance tests reveal which assumptions were wrong. It measures whether a model asks the right questions or guesses. 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: Hidden spec acceptance tests pass; count of clarifying questions and wrong assumptions.
Setup notes: Synthetic Python storefront repo (batch2/p06/repo) with a deliberately underspecified ticket. Clarification loop is emulated: the agent may write up to 3 questions to QUESTIONS.md and stop; a script answers each question by keyword-matching it to a 9-item hidden spec (batch2/p06/hidden/spec.json; unmatched questions get 'use your best judgment') and resumes the same Claude Code session with --resume. Scored with 10 hidden acceptance tests. Tools: Read/Write/Edit/Glob/Grep/Bash, web disabled. user_interventions counts scripted answer rounds. The product-owner answers to the agent's clarifying questions were scripted in advance (not a live human). Claude Code's own reported cost for claude-haiku-5.5: $0.00664. Score: 7/10 hidden tests. 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
- $0.0066
- Wall time
- 23s
- Human step-ins
- 0
- Turns
- 10
| Model | Input tok | Output tok | Cost |
|---|---|---|---|
| AClaude Haiku 5.5anthropic/claude-haiku-5.5effort default (no --effort flag) · thinking on | 141,082 | 4,795 | $0.0066 |
Reproduce this run
- Use the use case prompt on the use case page.
- Same setup: Claude Haiku 5.5 (anthropic/claude-haiku-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: Hidden spec acceptance tests pass; count of clarifying questions and wrong assumptions.
- 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?
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
[
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"stop_reason": "end_turn",
"session_id": "[REDACTED]",
"total_cost_usd": 0.00664002,
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"cache_creation_input_tokens": 14898,
"cache_read_input_tokens": 126172,
"output_tokens": 4795,
"output_tokens_details": {
"thinking_tokens": 1161
},
"server_tool_use": {
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"web_fetch_requests": 0
},
"service_tier": "standard",
"cache_creation": {
"ephemeral_1h_input_tokens": 14898,
"ephemeral_5m_input_tokens": 0
},
"inference_geo": "global",
"iterations": [
{
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"output_tokens": 779,
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"cache_creation_input_tokens": 1072,
"cache_creation": {
"ephemeral_5m_input_tokens": 0,
"ephemeral_1h_input_tokens": 1072
},
"type": "message"
}
],
"speed": "standard",
"fallback_credit": null
},
"modelUsage": {
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"inputTokens": 12,
"outputTokens": 4795,
"cacheReadInputTokens": 126172,
"cacheCreationInputTokens": 14898,
"webSearchRequests": 0,
"costUSD": 0.00664002,
"contextWindow": 1000000,
"maxOutputTokens": 128000,
"thinkingTokens": 1161,
"canonicalModel": "claude-haiku-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": {
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"refused": {
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"by_type": {}
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"safety_stops": 0,
"is_error": false,
"num_turns": 10,
"subtype": "success",
"api_error_status": null,
"result": "Wishlist is in place and the full suite passes: 17 tests, 10 of them new.\n\n**What I added**\n- `store/wishlist.py` with `add_to_wishlist(session, product_id)`, `remove_from_wishlist(session, product_id)` and `get_wishlist(session)`, which returns a list of product ids in insertion order.\n- `store/db.py`: a `WISHLISTS` store keyed by the same owner key as carts, cleared by `reset()`.\n- `tests/test_wishlist.py`: covers add/get, idempotent add, removing a missing item, unknown products, per-session isolation, the returned list being a copy, and user wishlists persisting across sessions.\n\n**Choices I made without asking** (the ticket didn't specify these; I followed the cart module's conventions):\n- Adding an unknown product raises `NotFound`, the same as the cart.\n- Out-of-stock products can be saved. The cart blocks them, but a wishlist is for later, so I didn't copy that check.\n- Adding the same product twice is a no-op, and removing a product that isn't there does nothing.\n\n**Gap to decide on:** `auth.login` merges the guest cart into the user's cart, but it does not merge the guest wishlist. A guest who saves items and then logs in will lose them from view. I didn't change `login` because the ticket doesn't cover it. If you want the merge, it's a small addition to `login` and I can add it with a test.\n\nI haven't committed anything.",
"ttft_ms": 1346,
"type": "result",
"duration_ms": 22932,
"uuid": "[REDACTED]",
"ttft_stream_ms": 1243,
"time_to_request_ms": 243,
"first_content_frame_ms": 1243,
"queued_turn_count": 0,
"result_index": 0
}
]