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Run: 2026-09-29-01M3P2K50GD1GY56WCRN5TRW9G
Run Details
Model:
Claude Sonnet 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
13.3s
Cost:
$0.018114
Provider:
Claude Platform on AWS
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
Rain hammered the windows of Blackwood Manor the night Lord Edmund Harrow was found dead in his own locked study. Inspector Mara Quill arrived at midnight, her boots muddy, her umbrella broken, and her patience worn thin by the storm. The butler, a pale man named Cobb, led her through the grand hallway without once meeting her steady, questioning eyes. Inside the study, Lord Harrow slumped over his desk, one hand still tightly clutching a torn scrap of crimson silk. The door had been bolted from inside, the window latched, and the only key rested in the dead man's pocket. Quill knelt beside the body and noticed that the brandy glass on the desk was still perfectly and suspiciously full. Somewhere upstairs a clock struck twelve, and Quill realized that someone in the house was already quietly lying to her.
created_at
"2026-09-29T07:55:42.996Z"
9/29/2026, 7:55:42 AM
model
"anthropic/claude-sonnet-5.5-20260928"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3798
moderation_latency
(null)
generation_time
13274
tokens_prompt
46
tokens_completion
483
native_tokens_prompt
62
native_tokens_completion
1799
native_tokens_completion_images
(null)
native_tokens_reasoning
1515
native_tokens_cached
0
num_media_prompt
(null)
num_input_audio_prompt
(null)
num_media_completion
0
num_search_results
(null)
num_fetches
(null)
web_search_engine
(null)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"end_turn"
service_tier
"default"
usage
0.018114
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1790668542-ohZYk4cZ8jasldoDCOvi"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790668542-Jo8h8JefXdbyltXUOsFV"
upstream_id
"msg_011CfXNYLJtuM6sTefyWPNZ7"
provider_responses
0
endpoint_id
"99aaad94-923b-4fc1-b763-271ed5486f7a"
id
"msg_011CfXNYLJtuM6sTefyWPNZ7"
is_byok
false
latency
597
model_permaslug
"anthropic/claude-sonnet-5.5-20260928"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.018114
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Claude Platform on AWS"
response_cache_source_id
(null)
data_region
"global"
workspace_id
"97e315e5-d303-487d-83c1-83180e8a13d4"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
7
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20