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Run: 2026-02-24-01KJ8WZEVB25E04AAQNRCC0JWB
Run Details
Model:
Claude Opus 4.6 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
19.1s
Cost:
$0.033155
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
94.24%
Matches word count
(details)
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 10 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 silent against the dark cold winter sky. Detective Harris stepped through the heavy front door without knocking. A body lay crumpled at the bottom of the stairs. Blood had pooled beneath the victim's head like dark wine. She knelt beside the man and studied his pale face. His expression held surprise, as if death came without warning. The grandfather clock in the hallway had stopped at midnight. Five guests had been staying in the house that night. Each one claimed to have been sleeping through the murder. No one had heard a thing, or so they claimed. Harris pulled her notebook out and began writing detailed notes. The dead man was Richard Cole, owner of this estate. His wife stood weeping softly at the top of the stairs. Someone in this house was lying, and she would know. The truth always revealed itself if you asked enough questions. She looked up at the frightened faces watching from above. One of you knows exactly what happened here tonight, she said. The silence that followed told her more than any words could.
created_at
"2026-02-24T22:40:36.214Z"
2/24/2026, 10:40:36 PM
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1417
moderation_latency
213
generation_time
18790
tokens_prompt
46
tokens_completion
540
native_tokens_prompt
61
native_tokens_completion
1314
native_tokens_completion_images
(null)
native_tokens_reasoning
261
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
0.033155
router
(null)
provider_responses
0
endpoint_id
"a8708fb9-08ea-43bb-a3b1-165c87ef09df"
id
"12bc654f-e851-4935-8fb6-0f331898d695"
is_byok
false
latency
1329
model_permaslug
"anthropic/claude-4.6-opus-20260205"
provider_name
"Amazon Bedrock"
status
200
api_type
"completions"
id
"gen-1771972836-22LFoKIz3CBhR9Nm3Qku"
upstream_id
"12bc654f-e851-4935-8fb6-0f331898d695"
total_cost
0.033155
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
Evaluation details
Result
Evaluator
Details
Meta Data
94.24%
Matches word count
n/a
neededClean
false
sentences
18
wordCounts
0
11
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10
10
10
11
10
12
11
13
10
14
10
15
10
16
11
17
11