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Run: 2026-07-25-01KYCPXJ2QXVYZZYYSGP4TK92Y
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
10.1s
Cost:
$0.010025
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
68.52%
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
Rain hammered the slate roof of Thornbury Hall while the guests pretended not to notice the empty chair at dinner. Lady Margaret Ashcombe raised her glass, and the candlelight caught a tremor she had never permitted anyone to witness. "He is merely delayed," she announced, though the storm had closed the only road three hours before the soup arrived. Across the table, Dr. Elias Wren studied his reflection in a silver spoon and decided the truth could wait. The butler, Havers, entered without knocking, which in thirty-one years of faithful service he had never once done before. He bent to whisper, and Lady Margaret's glass met the tablecloth with a sound like a small bone breaking. Nobody spoke, because the words had already arrived in the room ahead of him, uninvited, wearing everyone's private suspicions. "The boathouse," Havers said finally, and his voice cracked open on the second syllable like ice under a boot. Six people rose together, and six shadows lurched across the portraits of ancestors who had kept far better secrets. Outside, the rain washed the gravel path clean of every footprint except the ones leading down toward the water.
created_at
"2026-07-25T13:20:02.14Z"
7/25/2026, 1:20:02 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2311
moderation_latency
(null)
generation_time
10012
tokens_prompt
46
tokens_completion
297
native_tokens_prompt
60
native_tokens_completion
389
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
0.010025
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqtKpMXLpaSVNUVPhkM"
is_byok
false
latency
2299
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-1784985602-bw7glaxbdxx6PbDMYU3R"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985602-YmEFwJXrrmzGBPu1wW0c"
upstream_id
"msg_011CdNqtKpMXLpaSVNUVPhkM"
total_cost
0.010025
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
68.52%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
20
1
19
2
20
3
19
4
19
5
19
6
19
7
19
8
19
9
19