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Run: 2026-07-25-01KYCR51GZ22ZNMJACYF4Q1ZRK
Run Details
Model:
Claude Opus 5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
25.4s
Cost:
$0.058175
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 Marlowe House since midnight, and by dawn the gravel drive resembled a shallow river. Mrs. Ada Pemberton, who never slept past five, discovered the library door standing wide open, which had never happened before. Inside, the fire had died to grey ash, and the tall clock on the landing counted seconds with terrible patience. Sir Edmund Vale sat in his reading chair, facing the window, one hand open upon the arm as though gesturing. She said good morning twice before noticing the dark stain spreading beneath him, black as spilled ink on the carpet. The letter knife from the desk lay six feet away, wiped clean, resting neatly parallel to the fallen fireplace poker. Ada did not scream, because screaming was for women in novels, and she had a household of eleven to consider. Instead she noted the time, half past six, and that both French windows had been bolted firmly from the inside. Whoever had done this thing was therefore still asleep upstairs, or pretending, beneath the roof she had polished for decades. She closed the door, turned the key, and walked slowly to the telephone with the steady gait of long service. The operator asked which service she required, and Ada answered police, twice, so that there would be no possible mistake.
created_at
"2026-07-25T13:41:35.91Z"
7/25/2026, 1:41:35 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4234
moderation_latency
(null)
generation_time
25291
tokens_prompt
46
tokens_completion
625
native_tokens_prompt
60
native_tokens_completion
2315
native_tokens_completion_images
(null)
native_tokens_reasoning
304
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
0.058175
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsXh6vKuhCX4N1H1dQb"
is_byok
false
latency
1495
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-1784986895-cl44uAqdAs7T2acfETQ3"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784986895-rjvNBmEosbhVI6Awh59H"
upstream_id
"msg_011CdNsXh6vKuhCX4N1H1dQb"
total_cost
0.058175
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
11
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20
10
20