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Run: 2026-07-25-01KYCRARDAWFASY9K0TV38QPBS
Run Details
Model:
Claude Opus 5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
31.0s
Cost:
$0.075025
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
88.89%
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 Marguerite Vance parked beside the stone fountain, killed the engine, and listened to rain drumming steadily on the roof. A constable waited under the portico, hunched inside a dripping cape, holding a black umbrella that had long since surrendered. "He's still inside the library, ma'am," the pale young constable said quietly, "and nobody has touched a single thing yet." Vance nodded, drew her coat tighter, and followed him through doors carved with grapevines into a vast cold marble hall. The house smelled of woodsmoke, lilies, and something faintly metallic that she recognized at once and chose not to mention. Sir Edmund Larkspur lay across the hearthrug, one arm outstretched, fingers still curled around the snapped stem of a wineglass. Blood had dried black in his silver hair, and beside him the fire had burned down to sullen orange embers. Six overnight guests sat in the drawing room across the corridor, drinking tea nobody wanted and saying nothing at all. One of them had killed him, and Vance intended to know which before the storm finally broke over the moor.
created_at
"2026-07-25T13:44:43.186Z"
7/25/2026, 1:44:43 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4409
moderation_latency
(null)
generation_time
30808
tokens_prompt
46
tokens_completion
632
native_tokens_prompt
60
native_tokens_completion
2989
native_tokens_completion_images
(null)
native_tokens_reasoning
330
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
0.075025
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsmW825Vrkowwef4coZ"
is_byok
false
latency
1549
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-1784987083-zDT5zom2jHKlmOz7CDqL"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784987083-Wt0TxMjp1UP8r06LhP7k"
upstream_id
"msg_011CdNsmW825Vrkowwef4coZ"
total_cost
0.075025
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
88.89%
Matches word count
n/a
neededClean
false
sentences
9
wordCounts
0
20
1
20
2
20
3
40
4
20
5
20
6
20
7
20
8
20