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Run: 2026-02-08-01KGZ0BE4M717DA8V0XZSD7478
Run Details
Model:
Claude Opus 4.5
Test:
N-Length Sentences
Scenario:
Write sentences with 5 words each
Duration:
7.5s
Cost:
$0.005195
Provider:
Anthropic
Evaluation summary
Score
Evaluator
Details Link
100.00%
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 eerily silent. Detective Morgan approached the door. Rain pelted her worn coat. She knocked three sharp times. No answer came from within. The door creaked slowly open. Darkness swallowed the grand foyer. Her flashlight cut through shadows. A chandelier hung above, shattered. Glass crunched beneath her boots. The smell hit her hard. Death had visited this place. She found him near stairs. Lord Ashworth lay quite still. Blood pooled on marble floors. His eyes stared at nothing. A knife protruded from chest. Someone wanted him very dead. Morgan knelt beside the body. This was no simple robbery. The victim's watch remained intact. Diamond cufflinks still adorned sleeves. She noticed something clutched tight. His fist held torn fabric. Red silk, expensive and rare. The killer left evidence behind. Morgan smiled ever so slightly. This case would prove interesting.
created_at
"2026-02-08T16:11:36.198422+00:00"
2/8/2026, 4:11:36 PM
model
"anthropic/claude-4.5-opus-20251124"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1638
moderation_latency
(null)
generation_time
7390
tokens_prompt
35
tokens_completion
182
native_tokens_prompt
44
native_tokens_completion
199
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
0.005195
router
(null)
provider_responses
0
id
"msg_01Tt8TYdpiWa5xQLvb9AX2QF"
status
200
is_byok
false
latency
1638
endpoint_id
"be883404-eb42-4b2d-b6e4-c7daa3aa8d62"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-opus-20251124"
api_type
"completions"
id
"gen-1770567088-HSiQxzIihF0PyEKIjpAd"
upstream_id
"msg_01Tt8TYdpiWa5xQLvb9AX2QF"
total_cost
0.005195
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
28
wordCounts
0
5
1
5
2
5
3
5
4
5
5
5
6
5
7
5
8
5
9
5
10
5
11
5
12
5
13
5
14
5
15
5
16
5
17
5
18
5
19
5
20
5
21
5
22
5
23
5
24
5
25
5
26
5
27
5