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Run: 2026-10-08-01M4DAMYE14D1BES557JC897K7
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
12.5s
Cost:
$0.001264
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
93.44%
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 fallen across Blackwood Manor since midnight, washing the gravel paths clean of every single footprint left behind. Detective Inspector Harold Finch arrived at dawn, his umbrella dripping onto the cold marble steps of the grand entrance hall. Lady Vivienne Ashworth lay motionless beside the fireplace, one hand still clutching a half-empty crystal glass of rare vintage sherry. Nobody in the household had heard a scream, and every guest swore they had been sound asleep in their beds. Finch knelt beside the body, noticing three oddities: a muddy boot, a torn letter, and one missing silver key. Somewhere above, a door creaked open, and footsteps began descending the long oak staircase slowly, deliberately, toward the hall below.
created_at
"2026-10-08T08:39:02.345Z"
10/8/2026, 8:39:02 AM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2614
moderation_latency
(null)
generation_time
12463
tokens_prompt
46
tokens_completion
473
native_tokens_prompt
62
native_tokens_completion
2515
native_tokens_completion_images
(null)
native_tokens_reasoning
2253
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
0.0012637
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791448742-d8KJJZ1m66MJKdhnwQiY"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791448742-RYZsCTLqWEYHddNbSPBj"
upstream_id
"msg_011CfpU8C1vNRPoYqEzeqYoc"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpU8C1vNRPoYqEzeqYoc"
is_byok
false
latency
805
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0012637
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
93.44%
Matches word count
n/a
neededClean
false
sentences
6
wordCounts
0
20
1
20
2
20
3
20
4
19
5
20