Model

Claude Sonnet 4.5

Test

N-Length Sentences

Scenario

Write sentences with 20 words each

Run ID

2026-02-08-01KGYZNTBV9TBENM659W92TW8H

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 Thornwood Affair The morning fog clung to Thornwood Manor like a shroud, obscuring the gardens where Lord Pemberton lay quite dead. Detective Sarah Chen arrived at precisely eight o'clock, her coat damp from the mist that refused to lift properly. The butler, Harrison, stood rigid by the entrance hall, his face pale as the marble columns flanking the doorway. "I discovered him at dawn, Detective," Harrison said, his voice trembling with emotion he struggled to carefully contain within. Lord Pemberton's body rested face-down in the rose garden, his evening clothes soaked through with morning dew and blood. A single champagne flute lay shattered nearby, its crystal fragments catching what little light penetrated the oppressive grey morning. The household staff gathered in nervous clusters, whispering anxiously about the events of last night's dinner party gone wrong. Lady Pemberton remained upstairs in her chambers, sedated by the family physician after her hysterical screaming woke the servants. Chen knelt beside the body, noting the distinctive bruising around the neck and the odd angle of the head. "Who was the last person to see Lord Pemberton alive?" she asked, surveying the faces of the assembled staff. Three people stepped forward simultaneously: the secretary, the gardener, and Lord Pemberton's own estranged daughter, Victoria, newly arrived from abroad.
created_at"2026-02-08T15:59:48.134553+00:00" Sunday, February 8th, 2026 at 3:59:48 PM GMT+00:00
model"anthropic/claude-4.5-sonnet-20250929" 
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moderation_latency146
generation_time7519
tokens_prompt35
tokens_completion278
native_tokens_prompt44
native_tokens_completion314
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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" 
usage0.004842
router(null)
provider_responses
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id"32a09c30-c556-42c5-ae65-ac184fb416d0" 
status200
is_byokfalse
latency1562
endpoint_id"d8bee848-f020-454a-b2be-4a7ce868f99f" 
provider_name"Amazon Bedrock" 
model_permaslug"anthropic/claude-4.5-sonnet-20250929" 
api_type"completions" 
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total_cost0.004842
cache_discount(null)
upstream_inference_cost0
provider_name"Amazon Bedrock" 

Evaluation details

Result Evaluator Details Meta Data
62.1565% Matches word count n/a
neededCleanfalse
sentences12
wordCounts
04
119
219
319
419
520
619
719
819
919
1019
1120