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Run: 2026-09-23-01M37PJPAYD7X6B6ND30PWQYD6
Run Details
Model:
Claude Opus 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
17.2s
Cost:
$0.034028
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 had raged over Blackwood Manor since early evening. Inside, the guests gathered near the fire, sipping warm brandy. Lord Ashworth had summoned them all with an urgent letter. Yet their host had not appeared since the dinner bell. Margaret, his niece, paced nervously beside the tall bay window. Colonel Hastings checked his pocket watch for the third time. Suddenly, a piercing scream echoed down the long east corridor. Everyone froze, their glasses suspended halfway between table and lips. The young maid, Elsie, stumbled into the room, trembling violently. "He is dead," she whispered, pointing toward the dark study. They rushed down the hallway, candles flickering against the walls. Lord Ashworth lay slumped across his desk, eyes wide open. A silver letter opener protruded from between his shoulder blades. The window was latched, the key still inside the lock. Somewhere in this house, a murderer was watching them all.
created_at
"2026-09-23T17:56:23.027Z"
9/23/2026, 5:56:23 PM
model
"anthropic/claude-opus-5.5-20260921"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4338
moderation_latency
(null)
generation_time
17147
tokens_prompt
46
tokens_completion
437
native_tokens_prompt
62
native_tokens_completion
1689
native_tokens_completion_images
(null)
native_tokens_reasoning
1367
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
0.034028
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.20.0; linux; x64))"
http_referer
(null)
request_id
"req-1790186183-zvrjYWh1WxmYB8gR0mIH"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790186183-UOXtzRaHxJ5OdlD2yUJl"
upstream_id
"msg_011CfLoVWgGkBPp2yExvVyQa"
provider_responses
0
endpoint_id
"3a2388bc-3740-4e64-a1f5-4e301726b6b9"
id
"msg_011CfLoVWgGkBPp2yExvVyQa"
is_byok
false
latency
1205
model_permaslug
"anthropic/claude-opus-5.5-20260921"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.034028
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
15
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
13
10
14
10