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Run: 2026-02-24-01KJ8VTZ0T5Q3856AMCNYX4KJZ
Run Details
Model:
Claude Opus 4.6 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
54.7s
Cost:
$0.113155
Provider:
Amazon Bedrock
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 old mansion stood at the end of Blackwood Lane, its windows dark and empty like the eyes of death. Detective Sarah Cole stepped out of her car and stared at the crime scene tape fluttering in the cold wind. She had seen many bodies in her career, but the call tonight had carried an unusual urgency in its tone. The victim was found in the library, slumped over a mahogany desk with a single gunshot wound to the head. His name was Edward Holloway, a wealthy collector of rare books and a man with no shortage of enemies around. Blood had pooled beneath his chair and dripped slowly onto a first edition novel that was now worth absolutely nothing. A half-empty glass of whiskey sat beside his hand, and the room smelled of gunpowder, leather, and something sickeningly sweet. Officer Daniels met her at the front door, his young face drained of color and his hands trembling with nerves. He explained that the housekeeper discovered the body at nine and had been screaming in the hallway ever since then. Sarah knelt beside the body, studying the wound, the angle of entry, and the peculiar expression frozen on his face. It was not fear she saw there, nor surprise, but something closer to recognition, as if he knew his killer. Every door had been locked from within, and each window was latched tight against the bitter cold of the night. Someone had killed Edward Holloway in a perfectly sealed room, and Detective Cole already knew this case would be different. She stood slowly, pulled on her gloves, and whispered to herself that the dead always find a way to speak.
created_at
"2026-02-24T22:20:40.354Z"
2/24/2026, 10:20:40 PM
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1494
moderation_latency
121
generation_time
54524
tokens_prompt
46
tokens_completion
1244
native_tokens_prompt
61
native_tokens_completion
4514
native_tokens_completion_images
(null)
native_tokens_reasoning
847
native_tokens_cached
0
num_media_prompt
(null)
num_input_audio_prompt
(null)
num_media_completion
0
num_search_results
(null)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"stop"
usage
0.113155
router
(null)
provider_responses
0
endpoint_id
"a8708fb9-08ea-43bb-a3b1-165c87ef09df"
id
"0f6758c3-55a9-42ee-983f-104b91683ebe"
is_byok
false
latency
1465
model_permaslug
"anthropic/claude-4.6-opus-20260205"
provider_name
"Amazon Bedrock"
status
200
api_type
"completions"
id
"gen-1771971640-b602JpZ2eJjFw3XEb0m9"
upstream_id
"0f6758c3-55a9-42ee-983f-104b91683ebe"
total_cost
0.113155
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
14
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20
10
20
11
20
12
20
13
20