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Run: 2026-07-25-01KYCR8SMPGEMBB17QWPDV454K
Run Details
Model:
Claude Opus 5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
24.3s
Cost:
$0.052000
Provider:
Amazon Bedrock
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 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 Bellhaven since Thursday, and by Sunday morning the churchyard had become a shallow swamp. Constable Merrow arrived first, boots sinking, torch beam trembling across the headstones like a man searching for something long lost. The body lay face down beside the vicar's toolshed, one arm outstretched, fingers closed around a handful of wet gravel. He recognised the coat immediately, green wax with a torn shoulder, because he had admired it in the pub Friday. It belonged to Alec Prine, who owned half of the valley and was loathed, quietly and thoroughly, by nearly everyone. Merrow crouched, felt for a pulse he knew was absent, and noticed the wound at the base of the skull. Something narrow and heavy had struck twice, perhaps three times, and the rain had washed the evidence into the mud. Behind him, the church bell began its call to service, indifferent, and the first parishioners came through the iron gate. He stood, spread his arms, and told them all to stop walking, though nobody at the front seemed to hear. Twelve people crossed the grass toward him, and one of them, he would later learn, had already killed twice before.
created_at
"2026-07-25T13:43:38.91Z"
7/25/2026, 1:43:38 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
5506
moderation_latency
(null)
generation_time
24231
tokens_prompt
46
tokens_completion
498
native_tokens_prompt
60
native_tokens_completion
2068
native_tokens_completion_images
(null)
native_tokens_reasoning
205
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
0.052
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsgmT7ivghXakPH8bxZ"
is_byok
false
latency
2848
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-1784987018-527SdqyXrtla0pWBikSj"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784987018-eQoBef790Zckq9nYjz7s"
upstream_id
"msg_011CdNsgmT7ivghXakPH8bxZ"
total_cost
0.052
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
100.00%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20