Model

Claude Haiku 4.5

Test

N-Length Sentences

Scenario

Write sentences with 10 words each

Run ID

2026-02-08-01KGYYXCJJ3RP8AMZCVF7P3N62

Model input

User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 10 words. Please make sure that each sentence has the same length. Only return the opening itself.

Model response

AI
# The Body in the Library The rain fell hard against the Victorian mansion's windows. Detective Sarah Chen stepped out of her unmarked sedan. The grand house loomed dark except for upstairs lights. A uniformed officer met her at the iron gates. "The victim is Margaret Ashford, age seventy-two," he said. Her body was discovered this morning by the maid. The scene is preserved upstairs in the east wing. Sarah climbed the spiral staircase with practiced, careful steps. The bedroom door stood open, revealing an unsettling, quiet scene. Margaret lay motionless upon her four-poster mahogany bed frame. Her silk nightgown was stained deep crimson with blood. An empty teacup sat on the nightstand beside her. The window behind her was open to the rain. Sarah's eyes narrowed as she surveyed the silent room. Something about this murder didn't feel quite right somehow. She turned to the officer waiting nervously in doorway. "Tell me everything you know about Margaret Ashford's life."
created_at"2026-02-08T15:46:23.534108+00:00" Sunday, February 8th, 2026 at 3:46:23 PM GMT+00:00
model"anthropic/claude-4.5-haiku-20251001" 
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency395
moderation_latency(null)
generation_time3154
tokens_prompt35
tokens_completion205
native_tokens_prompt44
native_tokens_completion227
native_tokens_completion_images(null)
native_tokens_reasoning0
native_tokens_cached0
num_media_prompt(null)
num_input_audio_prompt(null)
num_media_completion0
num_search_results(null)
origin"https://ncbench.com/" 
is_byokfalse
finish_reason"stop" 
native_finish_reason"stop" 
usage0.001179
router(null)
provider_responses
0
id"msg_01NPJLVEUJykecfkbxLgZvGb" 
status200
is_byokfalse
latency395
endpoint_id"41d2915a-92e6-4993-b537-210b4e10cba8" 
provider_name"Anthropic" 
model_permaslug"anthropic/claude-4.5-haiku-20251001" 
api_type"completions" 
id"gen-1770565579-Bk4xmz9FpgTmo1CdjdNj" 
upstream_id"msg_01NPJLVEUJykecfkbxLgZvGb" 
total_cost0.001179
cache_discount(null)
upstream_inference_cost0
provider_name"Anthropic" 

Evaluation details

Result Evaluator Details Meta Data
74.3316% Matches word count n/a
neededCleanfalse
sentences18
wordCounts
06
19
29
39
49
510
69
79
89
910
1010
119
129
139
149
159
169
179