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Run: 2026-07-25-01KYCPTF0QZB8997NXQZXP40V2
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
6.9s
Cost:
$0.007575
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
95.68%
Matches word count
(details)
Model input
User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 10 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
Rain hammered the slate roof of Thornbury Hall all night. Constable Ellis Vane arrived at precisely seven in the morning. The front door stood open, swollen wood scraping wet stone. Inside, a grandfather clock ticked against the silence like accusation. Lady Margery Thornbury lay sprawled across the library's Persian carpet. Her left hand clutched a torn page of yellowed sheet music. Blood had dried around a brass letter opener's ornate handle. Vane crouched, noting the absence of any struggle whatsoever nearby. Seven crystal glasses waited on the sideboard, six of them used. Someone had rearranged the chairs into a careful, deliberate circle. Outside, six houseguests watched from the terrace, saying absolutely nothing. Vane wondered which of them had already decided to lie.
created_at
"2026-07-25T13:18:20.701Z"
7/25/2026, 1:18:20 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1631
moderation_latency
(null)
generation_time
6818
tokens_prompt
46
tokens_completion
205
native_tokens_prompt
60
native_tokens_completion
291
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
0.007575
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqkrA1rhB1k5qKEv32w"
is_byok
false
latency
1631
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-1784985500-xOw9yHvVpWdl0EUUTlaa"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985500-8mkpb5DUu2Bq6fLZJDwh"
upstream_id
"msg_011CdNqkrA1rhB1k5qKEv32w"
total_cost
0.007575
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
95.68%
Matches word count
n/a
neededClean
false
sentences
12
wordCounts
0
10
1
10
2
10
3
10
4
10
5
11
6
10
7
10
8
11
9
10
10
10
11
10