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Run: 2026-07-25-01KYCPNBAYG3EEK53N278JX8M8
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
15.8s
Cost:
$0.009525
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
80.33%
Matches word count
(details)
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 rain had been falling on Whitmore Hall for three days, turning the gravel drive into a river of mud. Inspector Deborah Vance parked her car beneath the dripping yews and studied the house through her streaked, fogging windshield. Every window on the eastern wing blazed with light, though the hour had crawled well past two in the morning. A young constable met her at the door, his face the color of the wet stone beneath his boots. "He's in the library, ma'am," the boy said, and swallowed hard, unable to look directly at her steady gray eyes. Inside, the house smelled of woodsmoke, old paper, and something faintly metallic that she recognized before she saw anything. Lord Alistair Whitmore lay across his desk with a letter opener buried neatly between his fourth and fifth ribs. Seven people waited in the drawing room, each of them soaked to the skin, and each one telling a different story. None of them had left the estate that night, which meant the killer was still sitting on the velvet furniture. Vance removed her gloves, one finger at a time, and decided that the truth would arrive before the morning did.
created_at
"2026-07-25T13:15:33.094Z"
7/25/2026, 1:15:33 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1843
moderation_latency
142
generation_time
15586
tokens_prompt
46
tokens_completion
289
native_tokens_prompt
60
native_tokens_completion
369
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)
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
0.009525
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqYWHM31bxUhiiK1rFt"
is_byok
false
latency
1843
model_permaslug
"anthropic/claude-opus-5-20260723"
provider_name
"Amazon Bedrock"
status
200
user_agent
"langchainjs-openai/1.0.0 ((node/v24.18.0; linux; x64))"
http_referer
(null)
request_id
"req-1784985333-U6e1vndI6lGJ0YPqIj7D"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985333-vnoLTnudkUG7Aw60z7p1"
upstream_id
"msg_011CdNqYWHM31bxUhiiK1rFt"
total_cost
0.009525
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
response_cache_source_id
(null)
data_region
"global"
Evaluation details
Result
Evaluator
Details
Meta Data
80.33%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
20
1
19
2
20
3
19
4
20
5
19
6
19
7
21
8
20
9
20