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Run: 2026-07-25-01KYCQQ2MNCFKAS5AZ3BZH6F16
Run Details
Model:
Claude Opus 5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
41.3s
Cost:
$0.101350
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 cold rain had been falling on Marlow Hall for three days, and the gravel drive shone like wet coal. Inside, the housekeeper Agnes Pryor lit the lamps at four o'clock because the winter dark arrived early and stayed late. She counted seven faces at dinner, though only six would still be breathing when the grandfather clock struck eleven tonight. The body was discovered in the library, face down on the Turkish carpet beside an overturned decanter of good brandy. Sir Edmund Marlow had swallowed something bitter, and the doctor arrived much too late to argue about the exact cause. Agnes stood in the doorway with her ring of keys pressed hard against her palm, saying absolutely nothing at all. She had seen who carried the last glass upstairs, and she fully intended to keep that knowledge entirely for herself. Outside, the rain kept falling steadily, washing the long drive clean of every tyre track and every single hurried footprint. By morning the police would arrive, ask their careful questions, and find six people offering six identical answers already polished. One of those six answers was a lie, and Agnes Pryor was the only person in the house who knew.
created_at
"2026-07-25T13:33:58.301Z"
7/25/2026, 1:33:58 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4459
moderation_latency
(null)
generation_time
41205
tokens_prompt
46
tokens_completion
878
native_tokens_prompt
60
native_tokens_completion
4042
native_tokens_completion_images
(null)
native_tokens_reasoning
577
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
0.10135
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNrwxnoH48ZB3BCmPXLw"
is_byok
false
latency
1875
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-1784986438-RA7dp3abSAoiMrfKS4FT"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784986438-YmLaFhCUpcKOd77Dyrvc"
upstream_id
"msg_011CdNrwxnoH48ZB3BCmPXLw"
total_cost
0.10135
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