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Run: 2026-07-25-01KYCQXZ611935VMD4YF0NT5Z2
Run Details
Model:
Claude Opus 5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
32.3s
Cost:
$0.079950
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. Inspector Della Hart parked beside the fountain, killed the engine, and watched water spill from a cracked stone lion's mouth. A young constable waited under the portico, holding an umbrella that had already surrendered to the wind an hour earlier. He looked pale, and Della decided the body inside must be worse than the sergeant's careful telephone call had suggested. The library smelled of woodsmoke, spilled brandy, and something metallic that she recognized long before she saw its actual source. Sir Edmund Voss lay face down across the hearthrug, one arm outstretched toward the fireplace and its cold gray ashes. A brass letter opener stood upright between his shoulder blades, driven deep by someone who had very clearly meant it. Six houseguests sat in the drawing room across the hall, each insisting they had heard nothing at all unusual overnight. Della took out her notebook, wrote the time, and understood that at least one of them was almost certainly lying. Outside, the rain kept falling, patiently washing away whatever evidence the killer had been careless enough to leave out there.
created_at
"2026-07-25T13:37:44.136Z"
7/25/2026, 1:37:44 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4069
moderation_latency
(null)
generation_time
32109
tokens_prompt
46
tokens_completion
721
native_tokens_prompt
60
native_tokens_completion
3186
native_tokens_completion_images
(null)
native_tokens_reasoning
416
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
0.07995
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsEcE1iZQF2nQBNaidY"
is_byok
false
latency
1515
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-1784986664-qD7GgpHjISByUyPMMaE1"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784986664-QlQXUlu8C6prEfDVfgzM"
upstream_id
"msg_011CdNsEcE1iZQF2nQBNaidY"
total_cost
0.07995
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