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Run: 2026-02-16-01KHK96FDM5QNJZZQRRDWBG8YB
Run Details
Model:
GPT-5.1
Test:
N-Length Sentences
Scenario:
Write sentences with 5 words each
Duration:
46.8s
Cost:
$0.021231
Provider:
OpenAI
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 5 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
Rain smeared the city lights. Detective Mara Quinn watched silently. Patrol cars jittered with reflections. The river carried oily secrets. Tonight, one surfaced without consent. They'd found him under Pierseventeen. Not floating; nailed beneath ladders. Mara ducked beneath the tape. Cold mist pearled on eyelashes. The uniformed sergeant looked shaken. He offered gloves, avoided conversation. Mara snapped them on carefully. The body's suit was expensive. Cufflinks glinted like tiny mirrors. His throat was neatly opened. No blood stained the boards. It had been raining hours. Everything should've washed red downstream. Instead, the planks remained clean. Someone killed him somewhere else. Then brought him here ceremoniously. Mara studied the careful nails. Four spikes, equidistant, stainless steel. A crude cross, disturbingly precise. The tide lapped, whispering measurements. Somewhere above, traffic hummed obliviously. Mara finally asked the sergeant. “Who discovered him, what time?” “Fisherman, around four this morning.” “Name's on the report, Lieutenant.” She crouched, searching his pockets. Wallet missing, phone still present. Locked screen displayed one notification. Unknown number: one unanswered call. Time matched the fisherman's story. Mara pocketed the cold device. “Get me prints from pilings.” “And pull cameras along Riverside.” Her partner, Jensen, arrived breathless. He studied the arranged corpse. “You sure this isn't theater?” Mara answered without looking up. “Theater sells tickets, not coffins.” Wind shifted, carrying something sour. Jensen sniffed, face tightening slightly. “Smell that? Industrial, maybe bleach.” Mara tasted the air thoughtfully. Somewhere pipes hissed beneath concrete. “Killer cleaned him,” she murmured. “Then chose this place deliberately.” Sirens wailed farther along riverfront. Another crime scene, or ambulance. Mara felt timing coil tight. One body rarely walked alone.
created_at
"2026-02-16T13:11:38.797196+00:00"
2/16/2026, 1:11:38 PM
model
"openai/gpt-5.1-20251113"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
5009
moderation_latency
(null)
generation_time
46662
tokens_prompt
46
tokens_completion
1212
native_tokens_prompt
41
native_tokens_completion
2118
native_tokens_completion_images
0
native_tokens_reasoning
1650
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
0.02123125
router
(null)
provider_responses
0
id
"resp_0e3ba7bb16006953016993175ba73081969d80ff6576bfbb42"
status
200
is_byok
false
latency
203
endpoint_id
"764eb97f-8bab-4326-b29b-7a8799b00a70"
provider_name
"OpenAI"
model_permaslug
"openai/gpt-5.1-20251113"
api_type
"completions"
id
"gen-1771247451-AtYPionoM0tvoDwbn2cz"
upstream_id
"resp_0e3ba7bb16006953016993175ba73081969d80ff6576bfbb42"
total_cost
0.02123125
cache_discount
(null)
upstream_inference_cost
0
provider_name
"OpenAI"
Evaluation details
Result
Evaluator
Details
Meta Data
91.8367%
Matches word count
n/a
neededClean
false
sentences
49
wordCounts
0
5
1
5
2
5
3
5
4
5
5
5
6
5
7
5
8
5
9
5
10
5
11
5
12
5
13
5
14
5
15
5
16
5
17
5
18
5
19
5
20
5
21
5
22
5
23
5
24
5
25
5
26
5
27
10
28
5
29
5
30
5
31
5
32
5
33
5
34
5
35
10
36
5
37
5
38
15
39
5
40
5
41
5
42
5
43
5
44
10
45
5
46
5
47
5
48
5