Run: 2026-10-08-01M4DAN8MZTX6A04Z7VJN6P8FC

Run Details

Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
9.6s
Cost:
$0.000909
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

AI
The rain had fallen on Ashford Manor for three relentless days, and nobody inside the house could sleep soundly anymore. At dawn, the housekeeper found Lord Edmund Vale dead behind his locked study door, a half-written letter beside his hand. Detective Inspector Harriet Mace arrived within the hour, carrying nothing but a notebook and a cold, steely patience rarely shown. Every person in the manor had a motive, and Harriet intended to find the one who had reason to lie.
created_at"2026-10-08T08:39:12.81Z" 10/8/2026, 8:39:12 AM
model"anthropic/claude-haiku-5.5-20261007"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency3047
moderation_latency(null)
generation_time9600
tokens_prompt46
tokens_completion328
native_tokens_prompt62
native_tokens_completion1805
native_tokens_completion_images(null)
native_tokens_reasoning1639
native_tokens_cached0
num_media_prompt(null)
num_input_audio_prompt(null)
num_media_completion0
num_search_results(null)
num_fetches(null)
web_search_engine(null)
origin"https://ncbench.com/"
is_byokfalse
finish_reason"stop"
native_finish_reason"end_turn"
service_tier"default"
usage0.0009087
router(null)
user_agent"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer(null)
request_id"req-1791448752-beRuZ3bjvxUtXEGI7Lvy"
session_id(null)
preset_id(null)
api_type"completions"
id"gen-1791448752-FwdykGCqcQUQ9pMPAP06"
upstream_id"msg_011CfpU8xvtsTFfZE3mSHFv7"
provider_responses
0
endpoint_id"b6cdf493-3a61-441f-a134-e7944fddb980"
id"msg_011CfpU8xvtsTFfZE3mSHFv7"
is_byokfalse
latency714
model_permaslug"anthropic/claude-haiku-5.5-20261007"
provider_name"Claude Platform on AWS"
status200
total_cost0.0009087
cache_discount(null)
upstream_inference_cost0
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
neededCleanfalse
sentences4
wordCounts
020
120
220
320