NC Bench
Overview
About
Tests
Models
Model
Claude Sonnet 4.5
Test
N-Length Sentences
Scenario
Write sentences with 20 words each
Run ID
2026-02-08-01KGYZKN1DEPF1NTJ7FFPV73EM
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 Last Symphony Rain hammered the conservatory windows while Detective Sarah Chen stood over the body of renowned conductor Victor Ashford, still clutching his baton tightly. Blood pooled beneath the piano, mixing with scattered sheet music that now bore crimson stains instead of musical notes alone. The orchestra members huddled together near the stage entrance, their elegant concert attire contrasting sharply with the horror etched upon faces. "Nobody leaves this building until I get answers," Sarah announced firmly, her voice cutting through the shocked silence like a knife. First violinist Margaret Winters stepped forward nervously, her hands trembling as she struggled to speak through tears streaming down her pale cheeks. "He was alive fifteen minutes ago, yelling at us during rehearsal as usual, demanding perfection for tomorrow night's prestigious performance," she whispered. Sarah's partner, Detective James Rodriguez, examined the conductor's podium carefully, noting the overturned music stand and suspicious wine glass nearby. The stage lights flickered ominously overhead, casting dancing shadows across the crime scene while thunder rolled menacingly through the darkening evening sky. Someone in this room had silenced Victor Ashford's demanding voice forever, and Sarah intended to discover exactly who and why tonight.
created_at
"2026-02-08T15:58:37.132844+00:00"
Sunday, February 8th, 2026 at 3:58:37 PM GMT+00:00
model
"anthropic/claude-4.5-sonnet-20250929"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1773
moderation_latency
147
generation_time
7756
tokens_prompt
35
tokens_completion
239
native_tokens_prompt
44
native_tokens_completion
274
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
0.004242
router
(null)
provider_responses
0
id
"2d00ab2c-51c8-473c-8f5e-513c05cb8c3c"
status
200
is_byok
false
latency
1772
endpoint_id
"d8bee848-f020-454a-b2be-4a7ce868f99f"
provider_name
"Amazon Bedrock"
model_permaslug
"anthropic/claude-4.5-sonnet-20250929"
api_type
"completions"
id
"gen-1770566308-rdLmSevroZCptXQMlWZP"
upstream_id
"2d00ab2c-51c8-473c-8f5e-513c05cb8c3c"
total_cost
0.004242
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
Evaluation details
Result
Evaluator
Details
Meta Data
42.3671%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
4
1
23
2
20
3
21
4
21
5
22
6
22
7
20
8
22
9
21