NC Bench
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Run: 2026-02-16-01KHK9FWJC3YC0HBNGXVNF7ZP3
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
17.8s
Cost:
$0.012221
Provider:
OpenAI
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
Rain hammered the station roof, disguising footsteps and whispered arguments. Detective Mara Kline watched commuters scatter, clutching umbrellas like shields. The last train had already left, but nobody seemed departing. Instead, a nervous crowd pressed inward, orbiting the shuttered restroom. A guard waved urgently, spotting Mara's familiar plain gray overcoat. She pushed through murmuring bodies, perfume and wet wool mingling. The restroom door gaped open, chained awkwardly to cleaning equipment. Inside, fluorescent light flickered, painting everything jaundiced and disturbingly uncertain. The corpse sat upright on the toilet, suit meticulously pressed. Only his eyes were wrong, focused upward, astonished, still calculating. Water dripped steadily from the ceiling, ticking seconds between heartbeats. Mara noted the silence first, heavier than any gathered suspicion. No one screamed now; the fear had turned inward, watchful. Somebody here knew him, Mara thought, and wasn't surprised enough. Outside, the rain intensified, trapping every witness inside with murder.
created_at
"2026-02-16T13:16:18.359777+00:00"
2/16/2026, 1:16:18 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
5058
moderation_latency
(null)
generation_time
17529
tokens_prompt
46
tokens_completion
868
native_tokens_prompt
41
native_tokens_completion
1217
native_tokens_completion_images
0
native_tokens_reasoning
988
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
0.01222125
router
(null)
provider_responses
0
id
"resp_09faeed97d2a23990169931890093881978be717803b6d365c"
status
200
is_byok
false
latency
169
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771247759-6DQYEsYzUvP0xRWtWrTH"
upstream_id
"resp_09faeed97d2a23990169931890093881978be717803b6d365c"
total_cost
0.01222125
cache_discount
(null)
upstream_inference_cost
0
provider_name
"OpenAI"
Evaluation details
Result
Evaluator
Details
Meta Data
100.0000%
Matches word count
n/a
neededClean
false
sentences
15
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10
10
10
11
10
12
10
13
10
14
10