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Run: 2026-10-08-01M4DYEENZY6RTAD9H462T5KK4
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Max)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
1m 14s
Cost:
$0.010223
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 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 over Blackmoor Manor since dusk, turning the gravel drive into a river of silver mud. Inside the dim study, the tall grandfather clock struck eleven just as Inspector Helen Marsh stepped quietly across the threshold. The body of Lord Edmund Ashworth lay sprawled beside the cold fireplace, one hand still clutching a broken crystal tumbler. Seven guests were stranded within the manor tonight, and every single one of them had a strong motive for murder. Helen knelt beside the corpse, carefully noting the faint smell of bitter almonds that clung to his slightly parted lips. Behind her, the butler swore that nobody had left the house since dinner, though his trembling hands told another story. Tucked neatly beside an empty decanter lay a single white glove, its twin nowhere to be found in the mansion. Helen promptly sealed the glove in an evidence bag, certain that the killer had made one fatal mistake that night. Then, from somewhere high above them, a door slammed shut, and a woman's terrified scream echoed through the silent halls.
created_at
"2026-10-08T14:25:01.129Z"
10/8/2026, 2:25:01 PM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
45413
moderation_latency
(null)
generation_time
73746
tokens_prompt
46
tokens_completion
2542
native_tokens_prompt
62
native_tokens_completion
20434
native_tokens_completion_images
(null)
native_tokens_reasoning
20068
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
0.0102232
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791469501-UiTS5190LyoHMHgBxAkF"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791469501-C3LusA1biytBy6AiHMwc"
upstream_id
"msg_011CfpvWR1QbKwUpZkVATRy5"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpvWR1QbKwUpZkVATRy5"
is_byok
false
latency
831
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0102232
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
9
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20