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Run: 2026-07-25-01KYCPQ9XYDDSSV7Q4KGC6W489
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
9.2s
Cost:
$0.008750
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
80.33%
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 it showed no intention whatsoever of stopping before dawn. Inspector Halloran stood beneath the dripping portico, watching the constable fumble with a lantern that refused to stay lit. "He's in the library, sir," the young man said, finally abandoning the lantern and gesturing toward the half-open oak door. Inside, the smell hit first: gun smoke, brandy, and something older, like coins left too long in a closed fist. Lord Bramwell Ashgrove lay across his writing desk, one hand extended toward a letter that had been torn precisely in half. Halloran counted seven people crowded into the doorway behind him, each wearing an expression carefully arranged into appropriate grief. The clock on the mantelpiece had stopped at eleven forty-three, though the inspector noticed its key lying three feet away. "Nobody leaves this house tonight," he said quietly, and watched to see which of the seven faces betrayed relief.
created_at
"2026-07-25T13:16:37.187Z"
7/25/2026, 1:16:37 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2144
moderation_latency
115
generation_time
8976
tokens_prompt
46
tokens_completion
251
native_tokens_prompt
60
native_tokens_completion
338
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
0.00875
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqdEAcXhRTAg28vyBuV"
is_byok
false
latency
2144
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-1784985397-UKMmxqY6p0TBsPQgG02H"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985397-ERstsuXmcwetVozTuxFT"
upstream_id
"msg_011CdNqdEAcXhRTAg28vyBuV"
total_cost
0.00875
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
80.33%
Matches word count
n/a
neededClean
false
sentences
8
wordCounts
0
20
1
19
2
20
3
20
4
21
5
19
6
20
7
19