NC Bench
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Run: 2026-02-20-01KHY93TJS5Z90QJ7CG6GMYZKY
Run Details
Model:
Grok 4 Fast
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
2.9s
Cost:
$0.000273
Provider:
xAI
Evaluation summary
Score
Evaluator
Details Link
34.52%
Matches word count
(details)
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 10 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
The grand old Victorian mansion stood silently under the moonlit sky tonight. Fog rolled thickly in from the river, cloaking the estate's winding drive. Inspector Hale arrived swiftly after the butler's frantic late-night telephone call. He parked his sedan and stepped out onto the gravel path. The front door creaked open as thunder rumbled ominously in the distance. Inside the dimly lit hall, shadows danced across the ornate wooden walls. A scream echoed from the drawing room, piercing the heavy, tense silence. Hale rushed forward, his hand gripping the holstered pistol at his side. There, sprawled lifeless on the bloodstained Persian rug, lay Sir Reginald Blackwood. The victim's eyes stared blankly at the chandelier above, frozen in terror.
created_at
"2026-02-20T19:41:03.46Z"
2/20/2026, 7:41:03 PM
model
"x-ai/grok-4-fast"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1728
moderation_latency
(null)
generation_time
2325
tokens_prompt
46
tokens_completion
200
native_tokens_prompt
191
native_tokens_completion
527
native_tokens_completion_images
0
native_tokens_reasoning
367
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
0.0002732
router
(null)
provider_responses
0
endpoint_id
"c9586d9d-97ff-40ca-ae94-22504d6f9b7e"
id
"c977e40d-a29d-d362-5553-60a168bf0f56"
is_byok
false
latency
61
model_permaslug
"x-ai/grok-4-fast"
provider_name
"xAI"
status
200
api_type
"completions"
id
"gen-1771616463-pObxxPilZtMtwrtty6RW"
upstream_id
"c977e40d-a29d-d362-5553-60a168bf0f56"
total_cost
0.0002732
cache_discount
0.0000285
upstream_inference_cost
0
provider_name
"xAI"
Evaluation details
Result
Evaluator
Details
Meta Data
34.52%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
12
1
12
2
12
3
11
4
12
5
12
6
12
7
12
8
12
9
12