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Run: 2026-02-16-01KHKAYHE0GQRMZT00KTPHP2A6
Run Details
Model:
GPT-5 Nano
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
40.1s
Cost:
$0.001834
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
The clock in the hall struck midnight as rain hissed against the window and candles trembled in cold neglect there. A violin case lay open on the carpet, its velvet lining stained, secrets fluttering like moths within whispered corridors tonight. From the library stairs, a breath of smoke curled upward, and a body lay draped beneath a painter's lantern dimly. The detective, hooded by night and coffee, moved closer, noting torn pages, an overturned chair, and a single crimson feather. In the moonlit hall, whispers stitched themselves into the wallpaper, accusing shadows of keeping a secret no one uttered there. Outside, thunder rattled the gutted panes, and the city clock chimed twice, as if warning everyone to withhold answers tonight. The corpse wore a smile that did not belong to mourning, as if the kiss of truth numbed every witness. A rainsoaked stair led down to the kitchen, where the butler reported nothing, except the kettle singing a lonesome requiem. On the desk, a letter lay unopened, addressed to someone unnamed, the ink smeared like a map of hidden grievances. The detective drew a breath, determined to trace tremor of fear through rooms, apologies, and doors that refused to close. Somewhere, a violin string twitched, and the manor exhaled, inviting the reader to follow the first footsteps of suspicion tonight.
created_at
"2026-02-16T13:42:09.073407+00:00"
2/16/2026, 1:42:09 PM
model
"openai/gpt-5-nano-2025-08-07"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3826
moderation_latency
(null)
generation_time
39852
tokens_prompt
46
tokens_completion
1529
native_tokens_prompt
41
native_tokens_completion
4581
native_tokens_completion_images
0
native_tokens_reasoning
4288
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
0.00183445
router
(null)
provider_responses
0
id
"resp_023325c0cf27eccb0169931e88b5e8819095649ce50219cade"
status
200
is_byok
false
latency
120
endpoint_id
"50329d77-04e1-4979-a184-c33030289476"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5-nano-2025-08-07"
api_type
"completions"
id
"gen-1771249288-y8Ch3KhORQGuNRW1ksNu"
upstream_id
"resp_023325c0cf27eccb0169931e88b5e8819095649ce50219cade"
total_cost
0.00183445
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
11
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20
10
20