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Run: 2026-10-08-01M4DA15C53MSAYX79SSGC1M3M
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
12.2s
Cost:
$0.001181
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
100.00%
Matches word count
(details)
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 20 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
The rain had fallen without pause across the harbor town since Tuesday, and nobody in Westbrook remembered a colder November. Detective Inspector Helen Marsh stood beneath the dripping awning of the Gull and Lantern pub, watching officers unroll yellow tape. Inside, the body of Gerald Ashworth, the town's most generous benefactor, lay slumped forward across his old mahogany writing desk. Nobody had heard a shot, and the only witness, a nervous housekeeper, insisted she had seen nothing whatsoever that night. Marsh crouched beside the victim, noting the half-empty decanter, the scattered letters, and the faint, sweet scent of cloves lingering. Her sergeant, Tom Reilly, hovered at the doorway, clutching a damp notebook he had not yet begun to fill properly. Whoever had killed Gerald Ashworth had known exactly where he kept his secrets, and that frightened her most of all.
created_at
"2026-10-08T08:28:14.093Z"
10/8/2026, 8:28:14 AM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2773
moderation_latency
(null)
generation_time
12172
tokens_prompt
46
tokens_completion
509
native_tokens_prompt
62
native_tokens_completion
2349
native_tokens_completion_images
(null)
native_tokens_reasoning
2028
native_tokens_cached
0
num_media_prompt
(null)
num_input_audio_prompt
(null)
num_media_completion
0
num_search_results
(null)
num_fetches
(null)
web_search_engine
(null)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"end_turn"
service_tier
"default"
usage
0.0011807
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791448094-AdaQLKQdenBwLDVziPT5"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791448094-2iq7IEUSnT4RyPEaxEHI"
upstream_id
"msg_011CfpTJQfLrMKH5JYzTqjjB"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpTJQfLrMKH5JYzTqjjB"
is_byok
false
latency
714
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0011807
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Claude Platform on AWS"
response_cache_source_id
(null)
data_region
"global"
workspace_id
"97e315e5-d303-487d-83c1-83180e8a13d4"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
7
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20