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Run: 2026-07-25-01KYCPMT27KTZ7R0S1GQD6YZ2J
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
8.8s
Cost:
$0.009750
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
51.23%
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 arrived at midnight, sliding down the windows of Thornfield House like fingers searching for a way inside. Constable Merrow parked his bicycle beneath the yew tree and stared up at the single lamp still burning. He had received the telephone call at half past eleven, a woman's voice, very calm, saying: come quickly, please. Nobody answered the front door, so he pushed it open and found the hallway smelling faintly of lavender polish. A grandfather clock ticked somewhere deeper in the house, patient as a heartbeat, counting out the seconds he wasted. The library door stood ajar, spilling yellow light across the black tiles in one long, narrow, trembling rectangle. Inside, Sir Hugh Thornfield sat in his leather armchair with a letter opener buried neatly below his left collarbone. His eyes were open, his reading glasses folded on the table, his glass of port untouched and still warm. Six people slept upstairs that night, and every one of them had written to him begging for money recently. Constable Merrow removed his helmet, wiped the rain from his face, and understood that his quiet career had ended.
created_at
"2026-07-25T13:15:15.404Z"
7/25/2026, 1:15:15 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1865
moderation_latency
(null)
generation_time
8713
tokens_prompt
46
tokens_completion
288
native_tokens_prompt
60
native_tokens_completion
378
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
0.00975
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqXBqJYTr68ZxyZ9hvj"
is_byok
false
latency
1865
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-1784985315-Cothh2FFAahqPEQ4JCsV"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985315-37V2dhrOzbiTskBhorDJ"
upstream_id
"msg_011CdNqXBqJYTr68ZxyZ9hvj"
total_cost
0.00975
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
51.23%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
19
1
18
2
19
3
19
4
19
5
18
6
19
7
19
8
19
9
19