NC Bench
Overview
About
Tests
Models
Vendors
Run: 2026-02-16-01KHK95SHC12X9WNE27MQTQJ62
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
30.6s
Cost:
$0.017781
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 stitched silver lines across Harrowgate Station's cracked glass roof. Detective Mara Lyle arrived late, carrying yesterday's unsolved headlines folded. On platform three, the body lay arranged with unnatural precision. Commuters pressed backward, clutching umbrellas like shields against contagious misfortune. The stationmaster's whistle trembled, refusing duty, dangling from shaking fingers. Mara knelt beside the corpse, avoiding smeared chalk directional arrows. Someone had traced messages around him, letters looping through puddles. They glowed faintly beneath emergency lights, spelling nothing yet unsettling. The victim wore evening clothes unsuited for dawn's commuter train. A red carnation decorated his lapel, petals crisp despite weather. No blood marred the flower; everything else seemed meticulously ruined. Ticket inspector Holloway cleared his throat, words marching out reluctantly. "He arrived alone, Detective, bought return fare, never boarded anything." Mara studied Holloway's eyes, finding lies carefully tidied away somewhere. Somewhere behind announcements, a child laughed, bright and inappropriate here. The sound skittered across tracks, chased off by distant thunder. She checked the corpse's pockets, finding only sugar packets, receipts. Each receipt bore identical time stamps, different vendors, same signature. The signature matched the chalk letters curving sorrowfully around him. Behind Mara, platform speakers crackled, announcing a delay for investigations. Travelers groaned, yet nobody complained about sharing space with death. They only watched Mara, silently appointing her keeper of explanations. Rain thickened outside, turning station windows into mirrors of suspicion. Mara's reflection met the dead man's, neither offering helpful answers.
created_at
"2026-02-16T13:11:00.249444+00:00"
2/16/2026, 1:11:00 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
6343
moderation_latency
(null)
generation_time
30033
tokens_prompt
46
tokens_completion
1251
native_tokens_prompt
41
native_tokens_completion
1773
native_tokens_completion_images
0
native_tokens_reasoning
1409
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
0.01778125
router
(null)
provider_responses
0
id
"resp_06db7416180a2d75016993174594a88193b8390ddb4ad9dae0"
status
200
is_byok
false
latency
167
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771247429-Wzn43Zc4pXlYfdnGO9XZ"
upstream_id
"resp_06db7416180a2d75016993174594a88193b8390ddb4ad9dae0"
total_cost
0.01778125
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
24
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
15
10
16
10
17
10
18
10
19
10
20
10
21
10
22
10
23
10