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Run: 2026-02-18-01KHQ93WNJ9BV7FZX28AMVM5PK
Run Details
Model:
Claude Sonnet 4.6
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
7.4s
Cost:
$0.003777
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
86.88%
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 at the edge of town, its broken light casting shadows across the cold November shore. Nobody had visited the lighthouse keeper, Edmund Fray, for nearly three weeks, which struck his neighbor as deeply troubling. Margaret Hollis pushed open the rusted iron gate, her lantern flickering wildly against the sharp and unforgiving coastal wind. She had brought Edmund his usual Tuesday delivery of bread, salted fish, and the local paper he always loved. The door swung open before she could knock, revealing a dark hallway that smelled of copper and something far worse. Her lantern illuminated the stone floor where a single muddy boot print led toward the winding staircase above her head. Margaret called out Edmund's name twice, but only the groaning walls and the distant crashing waves answered her trembling voice. She climbed the narrow stairs slowly, gripping the cold rope railing, each wooden step crying out beneath her cautious feet. At the top, the lamp room door stood wide open, and Edmund Fray lay motionless beside his beloved brass telescope.
created_at
"2026-02-18T02:26:32.218635+00:00"
2/18/2026, 2:26:32 AM
model
"anthropic/claude-4.6-sonnet-20260217"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
694
moderation_latency
196
generation_time
6709
tokens_prompt
46
tokens_completion
286
native_tokens_prompt
44
native_tokens_completion
243
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
0.003777
router
(null)
provider_responses
0
id
"7301567d-1cfe-4b29-abdd-1bc229b770ef"
status
200
is_byok
false
latency
694
endpoint_id
"83d802cb-44f2-45a0-a9d5-cb9bf79777c8"
provider_name
"Amazon Bedrock"
model_permaslug
"anthropic/claude-4.6-sonnet-20260217"
api_type
"completions"
id
"gen-1771381584-NsLBjTMznpL1ixPltV61"
upstream_id
"7301567d-1cfe-4b29-abdd-1bc229b770ef"
total_cost
0.003777
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
Evaluation details
Result
Evaluator
Details
Meta Data
86.88%
Matches word count
n/a
neededClean
false
sentences
9
wordCounts
0
20
1
19
2
19
3
19
4
20
5
20
6
20
7
20
8
20