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Run: 2026-02-16-01KHK9B02PKN7TDTXZ6P5T731S
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
25.7s
Cost:
$0.013571
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 stained glass windows as the guests assembled in Ashcroft Manor, pretending civility over simmering resentments that evening. I had not planned to attend, yet Sir Lionel's cryptic telegram promised revelations impossible for any investigator ignoring this summons. The drawing room smelled of cigar smoke, expensive perfume, and something metallic beneath, faint yet persistent like a guilty memory. Lady Beatrice drifted between conversations, smile brittle, pearls twitching whenever her gaze brushed the locked study at the landing door. Colonel Hargrove monopolized the fireplace, booming anecdotes from forgotten campaigns, though his watchful eyes measured every entrance and exit carefully. Near the piano, Reverend Cole shuffled hymn sheets he would never play, glancing repeatedly at the decanter of whisky nearby. Only Marianne, Sir Lionel's ward, seemed genuinely cheerful, though her laughter stopped whenever footsteps sounded overhead in corridors above us. The butler, Pritchard, announced dinner precisely at eight, his gloved hands trembling as though the silver cloche concealed dynamite tonight. We had barely taken our seats when a thunderclap shook the chandeliers and extinguished three candles nearest Sir Lionel himself. When the lights flickered back, Sir Lionel slumped forward into his soup, a dark ribbon spreading silently across porcelain surface.
created_at
"2026-02-16T13:13:45.737551+00:00"
2/16/2026, 1:13:45 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
5267
moderation_latency
(null)
generation_time
25589
tokens_prompt
46
tokens_completion
1029
native_tokens_prompt
41
native_tokens_completion
1352
native_tokens_completion_images
0
native_tokens_reasoning
1078
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
0.01357125
router
(null)
provider_responses
0
id
"resp_0bb56778e878064201699317efca388195ac07d737f4731ad2"
status
200
is_byok
false
latency
159
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771247599-UzafVwt9EXfqgQ5mJGX0"
upstream_id
"resp_0bb56778e878064201699317efca388195ac07d737f4731ad2"
total_cost
0.01357125
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