NC Bench
Overview
About
Tests
Models
Model
Claude Haiku 4.5
Test
N-Length Sentences
Scenario
Write sentences with 20 words each
Run ID
2026-02-08-01KGYZ01HRVJVT71EBTNWXF1TH
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 Discovery The body lay sprawled across the mahogany desk, its lifeless eyes staring blankly at the ornate ceiling above. Detective Sarah Mitchell stepped into the study, her shoes clicking softly against the polished hardwood floor of the mansion. A pool of crimson blood had begun to congeal around the victim's head, suggesting death occurred hours before discovery. The victim was identified as Victor Ashford, a wealthy businessman known for his ruthless corporate dealings and numerous enemies. His right hand still clutched a fountain pen, as if he had been signing documents when the fatal blow struck. The window behind the desk stood open, cold December air flowing freely into the room and disturbing scattered papers everywhere. Sarah surveyed the scene methodically, noting that nothing appeared stolen or disturbed except for the overturned chair beneath the body. "Who discovered the body?" she asked the uniformed officer standing silently in the doorway, waiting for answers to emerge slowly.
created_at
"2026-02-08T15:47:49.907071+00:00"
Sunday, February 8th, 2026 at 3:47:49 PM GMT+00:00
model
"anthropic/claude-4.5-haiku-20251001"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
435
moderation_latency
(null)
generation_time
2702
tokens_prompt
35
tokens_completion
190
native_tokens_prompt
44
native_tokens_completion
214
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
0.001114
router
(null)
provider_responses
0
id
"msg_01L4CQAHjwTkEzBWfhE62Bgj"
status
200
is_byok
false
latency
435
endpoint_id
"41d2915a-92e6-4993-b537-210b4e10cba8"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-haiku-20251001"
api_type
"completions"
id
"gen-1770565666-eVmXLk7bPlFT0ZPJqFfx"
upstream_id
"msg_01L4CQAHjwTkEzBWfhE62Bgj"
total_cost
0.001114
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
66.1659%
Matches word count
n/a
neededClean
false
sentences
9
wordCounts
0
3
1
18
2
19
3
19
4
19
5
20
6
20
7
20
8
20