NC Bench
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Run: 2026-02-20-01KHY8AKH65AFGKMWXJTMBA45N
Run Details
Model:
Grok 4.1 Fast
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
14.3s
Cost:
$0.000661
Provider:
xAI
Evaluation summary
Score
Evaluator
Details Link
100.00%
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 thick fog shrouded the ancient mansion on the hilltop. Lightning flashed, illuminating the dark grand hall through cracked windows. Sir Reginald Harrington lay sprawled on the fine Persian rug. A pool of blood spread from beneath his lifeless head. Lady Eleanor screamed, her voice echoing through the vast house. The stern Inspector Blackwood arrived just as thunder crashed loudly. His keen eyes scanned the room for any vital clues. Guests nervously gathered, whispering about who could have done it. The storm raged fiercely, sealing everyone inside the old mansion.
created_at
"2026-02-20T19:27:17.042Z"
2/20/2026, 7:27:17 PM
model
"x-ai/grok-4.1-fast"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
469
moderation_latency
(null)
generation_time
14228
tokens_prompt
46
tokens_completion
377
native_tokens_prompt
191
native_tokens_completion
1288
native_tokens_completion_images
0
native_tokens_reasoning
1174
native_tokens_cached
341
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
0.00066105
router
(null)
provider_responses
0
endpoint_id
"9821aa0e-dce3-4c27-9716-161359123d0b"
id
"b4646bd4-626b-c1d8-c0f9-a2872ac80cbb"
is_byok
false
latency
133
model_permaslug
"x-ai/grok-4.1-fast"
provider_name
"xAI"
status
200
api_type
"completions"
id
"gen-1771615637-ovRJHVMKDg22VSE2LkSA"
upstream_id
"b4646bd4-626b-c1d8-c0f9-a2872ac80cbb"
total_cost
0.00066105
cache_discount
0.00002115
upstream_inference_cost
0
provider_name
"xAI"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
9
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10