NC Bench
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Run: 2026-02-20-01KHY7N9AV5MJWGKD1YTQHMXWZ
Run Details
Model:
Grok 4 Fast
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
4.7s
Cost:
$0.000264
Provider:
xAI
Evaluation summary
Score
Evaluator
Details Link
0.25%
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 grand Victorian manor loomed dark against the stormy night sky over the quiet English village. Inside the drawing room, guests gathered around the crackling fire, sharing stories of local legends and lore. Lady Eleanor Harrington, the elegant hostess, poured aged brandy into crystal glasses for her assembled friends. Suddenly, a sharp cry echoed from the upstairs corridor, freezing everyone in their elegant evening attire. Sir Reginald, her husband, rose quickly from his armchair and dashed toward the winding oak staircase. The group followed hesitantly, their footsteps thudding softly on the polished hardwood floors below. At the bedroom door, they found it ajar, with shadows dancing wildly from the flickering candlelight. Pushing it open, Sir Reginald gasped at the sight of blood pooling on the antique Persian rug. Lady Eleanor's lifeless body lay sprawled across the four-poster bed, her throat slashed deeply open. Detective Inspector Harrow arrived soon after, his keen eyes scanning the room for any telling clues.
created_at
"2026-02-20T19:15:38.472Z"
2/20/2026, 7:15:38 PM
model
"x-ai/grok-4-fast"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3066
moderation_latency
(null)
generation_time
4612
tokens_prompt
46
tokens_completion
271
native_tokens_prompt
191
native_tokens_completion
498
native_tokens_completion_images
0
native_tokens_reasoning
293
native_tokens_cached
152
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
0.0002644
router
(null)
provider_responses
0
endpoint_id
"c9586d9d-97ff-40ca-ae94-22504d6f9b7e"
id
"30beb738-348c-acdc-80f9-142d73ff22e2"
is_byok
false
latency
87
model_permaslug
"x-ai/grok-4-fast"
provider_name
"xAI"
status
200
api_type
"completions"
id
"gen-1771614938-a8mGE1W6BmSzM7U5VbFe"
upstream_id
"30beb738-348c-acdc-80f9-142d73ff22e2"
total_cost
0.0002644
cache_discount
0.0000228
upstream_inference_cost
0
provider_name
"xAI"
Evaluation details
Result
Evaluator
Details
Meta Data
0.25%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
16
1
17
2
16
3
16
4
16
5
14
6
16
7
17
8
16
9
16