NC Bench
Overview
About
Tests
Categories
Models
Vendors
Compare
Run: 2026-09-29-01M3P2DQ65C8JBPZ7C0BQXWABZ
Run Details
Model:
Claude Sonnet 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
18.0s
Cost:
$0.026524
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
90.00%
Matches word count
(details)
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
Rain hammered Blackwood Manor on the night Lord Ashby died. Inspector Mara Finch arrived near midnight, her coat soaked through. The butler waited in the foyer, pale and visibly trembling. Lord Ashby lay face-down, a dagger buried in his back. Mara knelt beside him and noticed the window was locked. Every door and window had been bolted from the inside. Someone in this house had killed him, and remained here. Mara turned to the butler and asked who found him. "I did, madam, at eleven, and the clock had stopped." Mara glanced at the clock, frozen at ten past nine. Someone wanted the murder to seem earlier than it was.
created_at
"2026-09-29T07:52:45.002Z"
9/29/2026, 7:52:45 AM
model
"anthropic/claude-sonnet-5.5-20260928"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3665
moderation_latency
(null)
generation_time
17987
tokens_prompt
46
tokens_completion
517
native_tokens_prompt
62
native_tokens_completion
2640
native_tokens_completion_images
(null)
native_tokens_reasoning
2415
native_tokens_cached
0
num_media_prompt
(null)
num_input_audio_prompt
(null)
num_media_completion
0
num_search_results
(null)
num_fetches
(null)
web_search_engine
(null)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"end_turn"
service_tier
"default"
usage
0.026524
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1790668365-KcWDzL5ZfidzudVPjB80"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790668365-w8LxuygYVwYa3eINImBC"
upstream_id
"msg_011CfXNKDSnofrdFhA6MoJME"
provider_responses
0
endpoint_id
"99aaad94-923b-4fc1-b763-271ed5486f7a"
id
"msg_011CfXNKDSnofrdFhA6MoJME"
is_byok
false
latency
668
model_permaslug
"anthropic/claude-sonnet-5.5-20260928"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.026524
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Claude Platform on AWS"
response_cache_source_id
(null)
data_region
"global"
workspace_id
"97e315e5-d303-487d-83c1-83180e8a13d4"
Evaluation details
Result
Evaluator
Details
Meta Data
90.00%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
20
9
10