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Run: 2026-02-18-01KHQ91M9HJ2B571GNC0D25EK7
Run Details
Model:
Claude Sonnet 4.6
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
6.1s
Cost:
$0.003462
Provider:
Anthropic
Evaluation summary
Score
Evaluator
Details Link
1.11%
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 old lighthouse stood alone on the cliff, its beam cutting through the fog like a warning. Detective Sarah Morse arrived at the scene just after midnight, her boots crunching on the wet gravel. She had seen many crime scenes before, but something about this one made her stomach turn uncomfortably. The body of a man lay sprawled across the lighthouse steps, one arm reaching toward the door. His expensive suit suggested wealth, yet his empty pockets told an entirely different and more troubling story. A single red rose had been placed deliberately on his chest, still fresh and impossibly, disturbingly perfect. Sarah pulled her coat tighter and studied the cliffs, certain that someone nearby was watching her carefully. The lighthouse keeper, an elderly woman named Ruth, stood trembling by the gate with frightened, hollow eyes. She claimed she had found him there at ten, but her shaking hands suggested something else entirely. Sarah made a note and looked out at the dark sea, knowing this night had just begun.
created_at
"2026-02-18T02:25:17.001731+00:00"
2/18/2026, 2:25:17 AM
model
"anthropic/claude-4.6-sonnet-20260217"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
409
moderation_latency
(null)
generation_time
6081
tokens_prompt
46
tokens_completion
263
native_tokens_prompt
44
native_tokens_completion
222
native_tokens_completion_images
(null)
native_tokens_reasoning
0
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
"stop"
usage
0.003462
router
(null)
provider_responses
0
id
"msg_01U1PFjiY2ndHTPnJuW8UGB7"
status
200
is_byok
false
latency
409
endpoint_id
"6d408764-7dd7-4626-bb87-a6cc1589bc86"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.6-sonnet-20260217"
api_type
"completions"
id
"gen-1771381510-0u5yigGzRc3I3vjBqX0z"
upstream_id
"msg_01U1PFjiY2ndHTPnJuW8UGB7"
total_cost
0.003462
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
1.11%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
17
1
17
2
17
3
17
4
17
5
17
6
17
7
17
8
17
9
17