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Run: 2026-02-08-01KGYYXXM3AKRWG82ZNP0MXJYM
Run Details
Model:
Claude Opus 4.5
Test:
N-Length Sentences
Scenario:
Write sentences with 5 words each
Duration:
8.0s
Cost:
$0.005770
Provider:
Anthropic
Evaluation summary
Score
Evaluator
Details Link
88.89%
Matches word count
(details)
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 5 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
The mansion stood in darkness. Rain pelted the old windows. Detective Harris approached the door. Her badge felt unusually heavy. Something terrible had happened here. A butler answered her knock. His face showed visible distress. "She's in the library, ma'am." Blood stained his white gloves. Harris noticed but said nothing. The library smelled like copper. Countess Morrison lay quite still. A knife pierced her chest. Her eyes stared at nothing. Pearls scattered across the floor. "Who discovered the body first?" Harris pulled out her notebook. The butler cleared his throat. "I did, around midnight, ma'am." His hands trembled quite visibly. Three suspects waited in chairs. Each one avoided eye contact. The widow's nephew looked pale. Her business partner seemed nervous. The young maid wept softly. Harris studied the crime scene. The window was slightly open. Muddy footprints marked the carpet. Someone had struggled here violently. The truth would emerge eventually.
created_at
"2026-02-08T15:46:45.449462+00:00"
2/8/2026, 3:46:45 PM
model
"anthropic/claude-4.5-opus-20251124"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1732
moderation_latency
(null)
generation_time
7874
tokens_prompt
35
tokens_completion
200
native_tokens_prompt
44
native_tokens_completion
222
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
0.00577
router
(null)
provider_responses
0
id
"msg_01Kj28uexYY9RJGna8aXzzuG"
status
200
is_byok
false
latency
1727
endpoint_id
"be883404-eb42-4b2d-b6e4-c7daa3aa8d62"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-opus-20251124"
api_type
"completions"
id
"gen-1770565596-nWvbqmW5QSavZbpJZ5Gz"
upstream_id
"msg_01Kj28uexYY9RJGna8aXzzuG"
total_cost
0.00577
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
88.89%
Matches word count
n/a
neededClean
false
sentences
27
wordCounts
0
5
1
5
2
5
3
5
4
5
5
5
6
5
7
10
8
5
9
5
10
5
11
5
12
5
13
5
14
10
15
5
16
10
17
5
18
5
19
5
20
5
21
5
22
5
23
5
24
5
25
5
26
5