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Run: 2026-07-25-01KYCR8H2DV1AWRQKBGPR4PBKX
Run Details
Model:
Claude Opus 5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
30.0s
Cost:
$0.071925
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 Ravensworth Hall since midnight, and by dawn the gravel drive resembled a shallow river. Inspector Margaret Cole parked beside the fountain, killed the engine, and sat listening to water drumming against the car roof. A young constable waited under the portico, hatless, holding an umbrella that the wind had already turned completely inside out. He said the body was in the library and nobody had touched anything, which she doubted on general principle alone. Inside, the house smelled of woodsmoke, wet wool, and the particular staleness of old rooms kept too warm too long. Sir Edmund Ravensworth lay face down across his desk, one arm extended toward a telephone that he never quite reached. Blood had dried black in his silver hair, and his reading glasses lay folded neatly beside the green leather blotter. Cole crouched, studied the wound, and decided that whoever swung the poker had done so with a terrible, unhurried patience. Nine people had slept beneath this roof last night, and one of them had washed, changed, and returned to bed. Outside, the rain kept falling, erasing footprints, tire tracks, and every small mercy an investigator might otherwise reasonably hope for. Cole straightened, wiped her hands, and asked the constable to start waking the household, one careful person at a time.
created_at
"2026-07-25T13:43:30.132Z"
7/25/2026, 1:43:30 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4188
moderation_latency
92
generation_time
29766
tokens_prompt
46
tokens_completion
655
native_tokens_prompt
60
native_tokens_completion
2865
native_tokens_completion_images
(null)
native_tokens_reasoning
320
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
0.071925
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsg7y7jJAjjKfmjMPiQ"
is_byok
false
latency
1552
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-1784987010-SGz47DGAlT0wlfQEd1te"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784987010-lixIQ4ALKbtE9gxHQQRm"
upstream_id
"msg_011CdNsg7y7jJAjjKfmjMPiQ"
total_cost
0.071925
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