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Run: 2026-07-25-01KYCPPM5W7R5SPVM5ZZZFRJDA
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
11.8s
Cost:
$0.012800
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 Ashcombe Manor for three days, and nobody thought to question why the gates stayed locked. Detective Inspector Marlowe Vance arrived at half past six, her boots sinking into gravel that smelled faintly of iron and rot. A young constable met her beneath the portico, holding an umbrella badly, his face the color of old candle wax. "Library, ma'am," he said, and then he said nothing else, because his throat closed around whatever description he had rehearsed. She walked past him without answering, because she had learned that silence made witnesses talk sooner than any question would. The hallway held forty-one portraits, and every painted eye seemed angled toward the same oak door at the corridor's cold end. Inside, the fire still burned, which meant somebody had fed it within the hour, long after the screaming reportedly stopped. Lord Ashcombe sat upright in his reading chair, hands folded, spectacles clean, a silver letter opener buried beneath his left collarbone. There was no blood on the carpet, none on his shirt, and none, remarkably, on the blade's exposed and polished handle. Vance crouched, studied the angle, and understood immediately that the old man had been arranged here rather than killed here. Behind her, the constable finally spoke: "The family's waiting in the drawing room, ma'am, all six of them, since midnight apparently." "Since midnight," she repeated, glancing at the clock, which had stopped at four, its hands frozen like a small accusation.
created_at
"2026-07-25T13:16:14.916Z"
7/25/2026, 1:16:14 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2867
moderation_latency
(null)
generation_time
11660
tokens_prompt
46
tokens_completion
387
native_tokens_prompt
60
native_tokens_completion
500
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
0.0128
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqba3ePLsyQhAXg9FiC"
is_byok
false
latency
2867
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-1784985374-n4KlRwO6gRVcvCgfNlOl"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985374-tGqwTG7gzPL2GusT85Fl"
upstream_id
"msg_011CdNqba3ePLsyQhAXg9FiC"
total_cost
0.0128
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
12
wordCounts
0
21
1
21
2
20
3
20
4
20
5
21
6
20
7
21
8
21
9
20
10
21
11
20