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Run: 2026-02-20-01KHY8648JHVDN9W0GDXW8BYWY
Run Details
Model:
Grok 4 Fast
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
4.5s
Cost:
$0.000480
Provider:
xAI
Evaluation summary
Score
Evaluator
Details Link
35.85%
Matches word count
(details)
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 rain-slicked streets of Victorian London gleamed under flickering gas lamps as Inspector Elias Crowe hurried toward the crime scene. A muffled scream echoed from the fog-shrouded alley, drawing curious eyes from shadowed doorways and upper windows alike. Pushing past the gathering crowd of wide-eyed onlookers, Crowe flashed his badge to the waiting uniformed constable. The body lay sprawled on cobblestones, pale face twisted in eternal surprise, blood pooling around the lifeless form. Silver-handled dagger protruded from the victim's chest, glinting coldly as thunder rumbled overhead in the stormy night. Crowe knelt beside the corpse, gloved hands probing pockets for clues amid the damp chill of early morning. No identification marked the elegant waistcoat, only a monogrammed handkerchief stained with the same crimson hue as the stones. Footprints trailed away into darkness, muddied steps leading toward the river's distant, whispering rush through the mist. A lady's scream pierced the air again, this time from a nearby carriage, shattering the tense hush of witnesses. Crowe rose swiftly, revolver drawn, heart pounding as he scanned the alley for the killer's unseen shadow lurking near.
created_at
"2026-02-20T19:24:50.337Z"
2/20/2026, 7:24:50 PM
model
"x-ai/grok-4-fast"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3141
moderation_latency
(null)
generation_time
4218
tokens_prompt
46
tokens_completion
314
native_tokens_prompt
191
native_tokens_completion
940
native_tokens_completion_images
0
native_tokens_reasoning
696
native_tokens_cached
190
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
0.0004797
router
(null)
provider_responses
0
endpoint_id
"c9586d9d-97ff-40ca-ae94-22504d6f9b7e"
id
"76a115e8-0dec-2e2c-14b9-79adc69c7a43"
is_byok
false
latency
583
model_permaslug
"x-ai/grok-4-fast"
provider_name
"xAI"
status
200
api_type
"completions"
id
"gen-1771615490-ZTkEJReTiuWiI8xeFMxT"
upstream_id
"76a115e8-0dec-2e2c-14b9-79adc69c7a43"
total_cost
0.0004797
cache_discount
0.0000285
upstream_inference_cost
0
provider_name
"xAI"
Evaluation details
Result
Evaluator
Details
Meta Data
35.85%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
21
1
19
2
18
3
18
4
18
5
18
6
19
7
17
8
19
9
19