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Run: 2026-09-23-01M37Q50G2M84AFC3C2PHG302R
Run Details
Model:
Claude Opus 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
20.1s
Cost:
$0.039248
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 fog rolled over Blackwood Manor like a gray shroud. Inspector Clara Hayes stepped from her car into the mud. A single candle burned in the highest window above her. The butler waited at the door, his face deathly pale. "Lord Ashford is in the library," he whispered to her. Clara followed him down a corridor lined with old portraits. Their painted eyes seemed to track every step she took. The library doors stood open, and cold air spilled out. Lord Ashford sat slumped in his chair by the fire. A silver letter opener was buried deep in his chest. Strangely, the fire was dead and the ashes stone cold. Clara knelt beside the body and noticed something even stranger. In his rigid fingers lay the torn queen of spades. Behind her, the butler spoke in a low, trembling voice. "That is the third card this month, Inspector," he said.
created_at
"2026-09-23T18:06:23.254Z"
9/23/2026, 6:06:23 PM
model
"anthropic/claude-opus-5.5-20260921"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4700
moderation_latency
(null)
generation_time
20085
tokens_prompt
46
tokens_completion
590
native_tokens_prompt
62
native_tokens_completion
1950
native_tokens_completion_images
(null)
native_tokens_reasoning
1663
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
0.039248
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.20.0; linux; x64))"
http_referer
(null)
request_id
"req-1790186783-M63jVxFZyIMhNX1u7HRu"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790186783-M2Dy3yHysBoWPJs1rTE3"
upstream_id
"msg_011CfLpFko4cvt8uNmL9W9Qf"
provider_responses
0
endpoint_id
"3a2388bc-3740-4e64-a1f5-4e301726b6b9"
id
"msg_011CfLpFko4cvt8uNmL9W9Qf"
is_byok
false
latency
1270
model_permaslug
"anthropic/claude-opus-5.5-20260921"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.039248
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