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Run: 2026-07-25-01KYCPR47X1Z9Y0XT45W3K8NX5
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
10.2s
Cost:
$0.010250
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
96.07%
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 stopped by the time Inspector Halloway arrived, leaving the gravel drive slick and glittering under weak lamplight. Blackthorn House loomed above him, its seventeen windows dark except one, where a curtain twitched and then fell perfectly still. He climbed the steps slowly, counting them out of habit, and found the front door standing open exactly four inches. Inside, the hall smelled of beeswax, wet wool, and something faintly metallic that made the back of his throat tighten. A grandfather clock ticked in the corner, and beside it a woman sat rigid on a chair, holding someone's gloves. "You'll be the detective," she said, not looking up, her voice as flat and gray as the flagstones beneath them. "He's in the library, and I want it understood that nobody here has touched anything at all since half-past nine." Halloway removed his hat, noting the mud on her hem, the tremor in her hands, the absence of any tears. "And you would be?" he asked, though he already suspected, from the ring she kept turning, exactly who she was. She raised her eyes then, pale as winter water, and answered, "I'm his wife, Inspector. I'm the one who found him."
created_at
"2026-07-25T13:17:04.13Z"
7/25/2026, 1:17:04 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2664
moderation_latency
(null)
generation_time
10122
tokens_prompt
46
tokens_completion
299
native_tokens_prompt
60
native_tokens_completion
398
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
0.01025
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqfDNYrgG7QxvPNw2oV"
is_byok
false
latency
2450
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-1784985424-A8hM2xWuVwMHjGT3VKqC"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985424-qQXwjMGYF6Gm1it8W2P1"
upstream_id
"msg_011CdNqfDNYrgG7QxvPNw2oV"
total_cost
0.01025
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
96.07%
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
21