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Run: 2026-02-24-01KJ8VDFA2B6SVWSKJ95RAVFY0
Run Details
Model:
Claude Sonnet 4.6 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
1m 10s
Cost:
$0.118248
Provider:
Anthropic
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 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 had stood at the edge of Harrow Bay for nearly two hundred years without a single incident. Tonight, that quiet record finally ended, as Detective Clara Marsh stepped carefully around the body sprawled on the stone floor. The victim, a well dressed man in his early fifties, lay face down with both his arms stretched wide apart. A single white candle still flickered on the windowsill, casting long shadows that danced like nervous fingers across the walls. Clara knelt beside the body and found a small folded note tucked very carefully beneath the dead man's right hand. She did not dare touch it just yet, knowing fully that the hours ahead would demand her very sharpest attention. Outside, the bitter wind screamed through the jagged rocks below, and the dark sea churned with wild and furious energy. Someone had committed this terrible crime with care, with patience, and with a cold calculating intelligence that Clara almost admired.
created_at
"2026-02-24T22:13:18.281Z"
2/24/2026, 10:13:18 PM
model
"anthropic/claude-4.6-sonnet-20260217"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
741
moderation_latency
(null)
generation_time
69846
tokens_prompt
46
tokens_completion
1954
native_tokens_prompt
61
native_tokens_completion
7871
native_tokens_completion_images
(null)
native_tokens_reasoning
1713
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
0.118248
router
(null)
provider_responses
0
endpoint_id
"6d408764-7dd7-4626-bb87-a6cc1589bc86"
id
"msg_01V1fTTM2w7bwymaQ3dmSDsf"
is_byok
false
latency
719
model_permaslug
"anthropic/claude-4.6-sonnet-20260217"
provider_name
"Anthropic"
status
200
api_type
"completions"
id
"gen-1771971198-uu9MoobUP6lxGGwBVfIB"
upstream_id
"msg_01V1fTTM2w7bwymaQ3dmSDsf"
total_cost
0.118248
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
8
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20