NC Bench
Overview
About
Tests
Models
Model
Claude Opus 4.6
Test
N-Length Sentences
Scenario
Write sentences with 10 words each
Run ID
2026-02-08-01KGZ050VMGXY31HRSW4VQW653
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
Messages
Meta
AI
The old mansion stood silent against the dark stormy night. Detective Morgan arrived at the scene just after midnight struck. Rain poured down heavily as she walked up the path. The front door was already open, creaking in the wind. A butler stood waiting, his face pale with visible shock. "The master is dead," he whispered with a trembling voice. She stepped inside and noticed muddy footprints across the floor. The grand hallway smelled of copper, smoke, and dying roses. A broken vase lay scattered near the winding spiral staircase. Upstairs, the body of Lord Ashworth waited in his study. He was slumped over his desk, a knife protruding deeply. The window behind him was shattered from an outside impact. Morgan pulled on her gloves and surveyed the gruesome scene. Three guests had been staying at the manor that weekend. Each one of them had a reason to want revenge. She turned to the butler and asked her first question. "Tell me exactly who was here when the screaming started." The investigation had begun, and the truth would soon emerge.
created_at
"2026-02-08T16:08:06.966824+00:00"
Sunday, February 8th, 2026 at 4:08:06 PM GMT+00:00
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1727
moderation_latency
(null)
generation_time
8204
tokens_prompt
35
tokens_completion
217
native_tokens_prompt
44
native_tokens_completion
255
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
0.006595
router
(null)
provider_responses
0
id
"msg_01HqSNWNRa28HgeezvvFdk7N"
status
200
is_byok
false
latency
1725
endpoint_id
"c926c048-563e-44b0-8434-95965bee924c"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.6-opus-20260205"
api_type
"completions"
id
"gen-1770566878-gwEncq8cFuqxTtFRII67"
upstream_id
"msg_01HqSNWNRa28HgeezvvFdk7N"
total_cost
0.006595
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
100.0000%
Matches word count
n/a
neededClean
false
sentences
18
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10
10
10
11
10
12
10
13
10
14
10
15
10
16
10
17
10