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Run: 2026-02-18-01KHQ926C5DHWE741J6KC3WCJA
Run Details
Model:
Claude Sonnet 4.6
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
6.3s
Cost:
$0.003702
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
21.72%
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 Dunmore Cove for nearly two hundred years without incident. Margaret Hale discovered the body just after dawn, her rubber boots sinking deep into the cold wet sand. The dead man lay face down beside the rusted iron door that led into the lighthouse base. She did not scream, which surprised her, because Margaret had always considered herself someone who would definitely scream. Instead she pulled her wool coat tighter and stared at the pale hand reaching toward the gray water. Detective Rowan Finch arrived forty minutes later, his black car cutting slowly through the thick morning coastal fog. He had seen seventeen dead bodies in his career, but something about this one felt immediately and deeply wrong. The lighthouse beam still rotated above them, casting its slow cold light across the rocky and indifferent shore. Finch crouched beside the body and noticed the small brass key clutched tightly inside the dead man's fist. Margaret watched him work and realized with a hollow certainty that she recognized the dead man's expensive brown shoes.
created_at
"2026-02-18T02:25:35.500612+00:00"
2/18/2026, 2:25:35 AM
model
"anthropic/claude-4.6-sonnet-20260217"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
763
moderation_latency
99
generation_time
6100
tokens_prompt
46
tokens_completion
291
native_tokens_prompt
44
native_tokens_completion
238
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
0.003702
router
(null)
provider_responses
0
id
"e22804f9-fa67-42ac-8f69-4be328b9f6f4"
status
200
is_byok
false
latency
762
endpoint_id
"83d802cb-44f2-45a0-a9d5-cb9bf79777c8"
provider_name
"Amazon Bedrock"
model_permaslug
"anthropic/claude-4.6-sonnet-20260217"
api_type
"completions"
id
"gen-1771381528-ywRv5OcspT0eF5hegjBK"
upstream_id
"e22804f9-fa67-42ac-8f69-4be328b9f6f4"
total_cost
0.003702
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
Evaluation details
Result
Evaluator
Details
Meta Data
21.72%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
18
1
18
2
17
3
18
4
18
5
18
6
19
7
18
8
18
9
19