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Run: 2026-07-25-01KYCQWCFGSP44YH0H50R773MA
Run Details
Model:
Claude Opus 5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
24.7s
Cost:
$0.056750
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 Ashgrove Manor since midnight, and by dawn the gravel drive resembled a shallow river. Constable Merrick arrived first, boots sinking, notebook already damp, wondering why a wealthy man would die on his own birthday. The housekeeper met him beneath the portico, wringing her apron, her thin face the exact colour of unbaked bread dough. She said nothing at all, only pointed down the corridor toward the library, where the heavy door stood half open. Inside, Sir Edmund Vale sat upright in his reading chair, eyes open, one hand curled around a silver fountain pen. A dark stain had spread across his waistcoat, and the unfinished letter beneath his fingers bore only three legible words. Merrick leaned closer, careful not to touch anything, and read the shaky message aloud twice: forgive me, she knew everything. Behind him, upstairs, a floorboard creaked once, then fell silent, and the young constable slowly realised he was not alone. Somewhere in that great sleeping house, a killer was still listening, waiting patiently for the endless storm to finally end.
created_at
"2026-07-25T13:36:52.219Z"
7/25/2026, 1:36:52 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4164
moderation_latency
(null)
generation_time
24499
tokens_prompt
46
tokens_completion
653
native_tokens_prompt
60
native_tokens_completion
2258
native_tokens_completion_images
(null)
native_tokens_reasoning
379
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
0.05675
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsAnxKSeXMBKWFGQbLt"
is_byok
false
latency
1560
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-1784986612-POHjhi6RbAMIbjWhIrpJ"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784986612-POA6GPEypDKBM5uJelpn"
upstream_id
"msg_011CdNsAnxKSeXMBKWFGQbLt"
total_cost
0.05675
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
9
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20