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Run: 2026-02-16-01KHK97K58D0EW4XX7AZTW3MDF
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
26.9s
Cost:
$0.017751
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 as Detective Mara Quinn waited. The last train had departed, leaving platforms slick and deserted. Somewhere downtrack, a maintenance signal blinked like a distant heartbeat. Mara checked her watch again, though time was irrelevant tonight. The anonymous message still glowed on her phone's cracked screen. COME ALONE TO PLATFORM THREE, MIDNIGHT, OR ANOTHER COMMUTER DISAPPEARS. Wind funneled through the underpass, carrying fried onions and smoke. A fluorescent light flickered overhead, buzzing like a wasp nest. Only one other person remained, slumped on a metal bench. He wore a janitor's uniform, cap shadowing his expressionless face. Mara catalogued exits, cameras, mirrors of rain on glass doors. Her partner should have been here, cracking jokes, diffusing nerves. Instead, her messages remained unread, little gray checkmarks accusing her. The station clock clicked over to midnight with mechanical indifference. From the tunnel, a train's horn wailed, wrong and distant. Yet the timetable showed nothing scheduled, no late freight tonight. The janitor stood, stretching slowly, eyes never leaving Mara's silhouette. His mop bucket rolled, wheels rattling like teeth in darkness. You came alone, Detective, he said, voice shredded by cigarettes. Mara's hand brushed her holster, fingers finding only empty leather. Somebody laughed then, hidden among columns, echoing with cruel amusement. The sound bounced wildly, refusing to reveal its true origin. Welcome to the end of the line, Detective Quinn tonight. Behind her, the last exit door clicked shut and locked.
created_at
"2026-02-16T13:11:55.406903+00:00"
2/16/2026, 1:11:55 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4817
moderation_latency
(null)
generation_time
26639
tokens_prompt
46
tokens_completion
1215
native_tokens_prompt
41
native_tokens_completion
1770
native_tokens_completion_images
0
native_tokens_reasoning
1407
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
0.01775125
router
(null)
provider_responses
0
id
"resp_0cab3a73fc4b235c01699317803d3c819580bbf4c5e960c4f4"
status
200
is_byok
false
latency
161
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771247488-LYWT1HA7eyTpXPfPmtfd"
upstream_id
"resp_0cab3a73fc4b235c01699317803d3c819580bbf4c5e960c4f4"
total_cost
0.01775125
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