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Run: 2026-02-16-01KHKAP4EPTP54JY9R26V20KRV
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
35.4s
Cost:
$0.021141
Provider:
OpenAI
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
Rain battered the sleepy harbor town as the night ferry arrived late, its horn echoing across fog-choked water and alleys. Detective Mara Leland stepped onto the slick pier, collar raised, already regretting answering the chief's midnight summons from her apartment. The ferry's gangway groaned downward, revealing anxious passengers clustered together, faces lit ghostly by swaying bulbs and emergency exit signs. At the edge of the crowd, Captain Rourke waited alone, white-knuckled grip crushing his cap, eyes avoiding Mara's approach entirely. She smelled copper beneath diesel fumes even before seeing the stretcher, sheeted shape too small for the fussing paramedics nearby. Rourke's voice cracked as he explained the passenger list showed thirty names, yet thirty-one bodies now waited onshore for identification. The extra corpse, uncovered with reluctant ceremony, displayed a single puncture beneath the ribs, shirt soaked black despite torrential rain. According to Rourke, every cabin door had been bolted from inside at docking, security cameras looping harmless seascapes all night. Mara studied the shivering line of travelers, calculating alibis and grudges while gulls screamed overhead like impatient, hungry jurors nearby. Somewhere among them, she knew, stood a killer who murdered in a locked room and added themselves to nobody's list.
created_at
"2026-02-16T13:37:29.221507+00:00"
2/16/2026, 1:37:29 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
32065
moderation_latency
(null)
generation_time
34741
tokens_prompt
46
tokens_completion
449
native_tokens_prompt
41
native_tokens_completion
2109
native_tokens_completion_images
0
native_tokens_reasoning
1821
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
"completed"
usage
0.02114125
router
(null)
provider_responses
0
id
"resp_0e3dda7655f1135b0169931d7552bc81968c116a59a8ed0b66"
status
200
is_byok
false
latency
177
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771249013-J2MiiZNTFjysPiqj0ysb"
upstream_id
"resp_0e3dda7655f1135b0169931d7552bc81968c116a59a8ed0b66"
total_cost
0.02114125
cache_discount
(null)
upstream_inference_cost
0
provider_name
"OpenAI"
Evaluation details
Result
Evaluator
Details
Meta Data
88.1959%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
21
1
20
2
20
3
21
4
20
5
21
6
20
7
20
8
20
9
20