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Run: 2026-09-23-01M37PMTDQSYDBGTFARFNHNVGZ
Run Details
Model:
Claude Opus 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
14.4s
Cost:
$0.029268
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
100.00%
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
The storm arrived at Blackwood Manor just before midnight struck. Inside, eight guests gathered near the fireplace, sipping warm brandy. Lord Ashford stood by the window, watching lightning split clouds. His wife, Eleanor, whispered something sharp to the young butler. Nobody noticed when the old grandfather clock suddenly stopped ticking. Then every candle in the drawing room flickered and died. A woman screamed, and glass shattered somewhere in the darkness. When the lights returned, Lord Ashford lay upon the carpet. A silver letter opener protruded from his motionless, bloodied chest. Detective Mara Quinn set down her glass and sighed heavily. "Nobody leaves this room," she said, her voice perfectly calm. Outside, the storm raged on, sealing every road from town. Somewhere among these trembling guests, a killer was smiling quietly.
created_at
"2026-09-23T17:57:32.744Z"
9/23/2026, 5:57:32 PM
model
"anthropic/claude-opus-5.5-20260921"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
5074
moderation_latency
(null)
generation_time
14348
tokens_prompt
46
tokens_completion
420
native_tokens_prompt
62
native_tokens_completion
1451
native_tokens_completion_images
(null)
native_tokens_reasoning
1150
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
0.029268
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.20.0; linux; x64))"
http_referer
(null)
request_id
"req-1790186252-YNOHLbr31vfJ7omNx9ZE"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790186252-FcepyPhAAtgT8JdIk0vE"
upstream_id
"msg_011CfLoafMoJxgu5pyUXMiBk"
provider_responses
0
endpoint_id
"3a2388bc-3740-4e64-a1f5-4e301726b6b9"
id
"msg_011CfLoafMoJxgu5pyUXMiBk"
is_byok
false
latency
1449
model_permaslug
"anthropic/claude-opus-5.5-20260921"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.029268
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Claude Platform on AWS"
response_cache_source_id
(null)
data_region
"global"
workspace_id
"97e315e5-d303-487d-83c1-83180e8a13d4"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
13
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10
10
10
11
10
12
10