Model

Claude Sonnet 4.5

Test

N-Length Sentences

Scenario

Write sentences with 20 words each

Run ID

2026-02-08-01KGYZK9XWSPEJWFNN1KNB8SS0

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

AI
The body lay sprawled across the mahogany desk, blood pooling beneath the chairman's silver hair in the moonlight shining through windows. Detective Sarah Chen arrived at precisely midnight, her badge glinting as she stepped over the yellow tape into the crime scene. "Victim is Robert Ashford, aged sixty-three, founder of Ashford Industries," Officer Martinez reported, consulting his notes with a grim expression on his face. The murder weapon, an ornate letter opener, rested nearby on the Persian rug, its blade still glistening with fresh crimson blood. "No signs of forced entry," Sarah observed, studying the locked windows and sealed doors with her practiced eye, noting every detail carefully. Three champagne glasses sat on the sideboard, two empty and one half-full, suggesting the victim had entertained guests before his death. The office safe stood open behind a painting, its contents apparently undisturbed despite the violence that had occurred just feet away tonight. "His secretary found him an hour ago when she returned for forgotten files," Martinez added, flipping through pages of notes. Sarah knelt beside the body, noticing defensive wounds on Ashford's hands and a peculiar expression frozen on his dying face forever. "Get me a list of everyone with building access tonight," she commanded, her mind already racing through possible suspects and motives.
created_at"2026-02-08T15:58:25.079672+00:00" Sunday, February 8th, 2026 at 3:58:25 PM GMT+00:00
model"anthropic/claude-4.5-sonnet-20250929" 
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cancelledfalse
latency1531
moderation_latency150
generation_time7036
tokens_prompt35
tokens_completion266
native_tokens_prompt44
native_tokens_completion297
native_tokens_completion_images(null)
native_tokens_reasoning0
native_tokens_cached0
num_media_prompt(null)
num_input_audio_prompt(null)
num_media_completion0
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is_byokfalse
finish_reason"stop" 
native_finish_reason"stop" 
usage0.004587
router(null)
provider_responses
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id"3574c60d-6bff-4601-bfd0-fbb1286a1021" 
status200
is_byokfalse
latency1526
endpoint_id"d8bee848-f020-454a-b2be-4a7ce868f99f" 
provider_name"Amazon Bedrock" 
model_permaslug"anthropic/claude-4.5-sonnet-20250929" 
api_type"completions" 
id"gen-1770566297-N6tSJhc26EjcJsH1qexa" 
upstream_id"3574c60d-6bff-4601-bfd0-fbb1286a1021" 
total_cost0.004587
cache_discount(null)
upstream_inference_cost0
provider_name"Amazon Bedrock" 

Evaluation details

Result Evaluator Details Meta Data
44.3899% Matches word count n/a
neededCleanfalse
sentences10
wordCounts
021
121
224
321
422
522
622
720
821
921