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Run: 2026-02-16-01KHK9X3RY40BAYBKS82PBP5EN
Run Details
Model:
GPT-5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
43.3s
Cost:
$0.027141
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 stitched the harbor's darkness, threadlike lines crossing streetlamps while gulls screamed like sirens drifting over shuttered shops at midnight. Detective Mara Kincaid arrived breathless, coat dripping, summoned by a terse call reporting disturbance at the old lighthouse just now. The keeper's door was ajar, splintered near the latch, and the wind kept tapping it like hesitant knuckles all night. Inside, lantern light wobbled across charts, spilled coffee, and a neat row of shells arranged like patient teeth on porcelain. The radio crackled with static and sea coordinates, then coughed silence, as though swallowing a confession halfway through its throat. Mara found footprints on the damp boards, two sets entering, only one leaving, smeared where something heavy had been dragged. At the base of the spiral stairs, blood threaded a curve like ink, disappearing where the shadows began their climb. The keeper lay higher, face toward the lens, eyes clouded, mouth puckered with salt, pockets turned out like pleading hands. A cracked watch ticked nearby, stubbornly faithful, though the room smelled of oil, iron, stormwater, and something newly extinguished here. There was no murder weapon in sight, only a folded letter beneath glass, beaded with spray, addressed to nobody particular. She read aloud, voice barely above the turning sea, words about debts, betrayal, and lightkeepers keeping darker secrets ashore untallied. Then the beacon shuddered, beam faltering, and distant boats answered with horns, while footsteps resumed above where no one waited.
created_at
"2026-02-16T13:23:57.200965+00:00"
2/16/2026, 1:23:57 PM
model
"openai/gpt-5-2025-08-07"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4167
moderation_latency
(null)
generation_time
43089
tokens_prompt
46
tokens_completion
1150
native_tokens_prompt
41
native_tokens_completion
2709
native_tokens_completion_images
0
native_tokens_reasoning
2368
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
0.02714125
router
(null)
provider_responses
0
id
"resp_0788ad4b2e3ea4860169931a417a5c8190b867dd5d62abe824"
status
200
is_byok
false
latency
202
endpoint_id
"7c2f859a-7890-4e8e-b1de-1cd1c0a800b4"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5-2025-08-07"
api_type
"completions"
id
"gen-1771248193-n8lXZLPpU7ItxTDJQAkM"
upstream_id
"resp_0788ad4b2e3ea4860169931a417a5c8190b867dd5d62abe824"
total_cost
0.02714125
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
12
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20
10
20
11
20