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Run: 2026-02-16-01KHKB0YHZJC2YSFJBR2G3R963
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
22.8s
Cost:
$0.015211
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 hammered the boarded windows as Detective Mara Quinn stepped into Ashcroft Manor, boots leaving nervous echoes behind her tonight. The electricity had failed hours earlier, leaving the vast house reliant on candles that guttered like frightened, watchful eyes everywhere. In the drawing room, ten guests clustered around a cold fireplace, their whispered accusations soft as ash on porcelain mantelshelf. On the Persian carpet between them lay Victor Harrow, party host, his tuxedo immaculate, his throat impossibly, surgically opened wide. Blood had stopped flowing long before Mara arrived, congealed into dark petals that framed his head like corrupted laurels tonight. Beside the body, someone had arranged three white chess pawns in a triangle, their bases touching, their meanings opaque deliberately. Mara noted muddy footprints near the French doors, each print sharply defined, then abruptly vanishing before reaching the bloodless corpse. Lightning flashed, illuminating every anxious face, and for an instant all eyes reflected the same guilty, hunted expression back inward. Outside, thunder rolled across the cliffs and swallowed the sound of distant sirens inching toward the manor through flooded roads. Until they arrived, Mara knew, everyone remained both witness and suspect, trapped together with the dead man and his secret.
created_at
"2026-02-16T13:43:11.147736+00:00"
2/16/2026, 1:43:11 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3713
moderation_latency
(null)
generation_time
22605
tokens_prompt
46
tokens_completion
1012
native_tokens_prompt
41
native_tokens_completion
1516
native_tokens_completion_images
0
native_tokens_reasoning
1250
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
0.01521125
router
(null)
provider_responses
0
id
"resp_0fb353f8eee35d740169931ed7af888190879a68f91df04a01"
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-1771249367-xodvP5sWKTFH7vhAJDCF"
upstream_id
"resp_0fb353f8eee35d740169931ed7af888190879a68f91df04a01"
total_cost
0.01521125
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
10
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20