Run: 2026-05-31-01KSYXDA7EWHSS9VZAYMQP396Y

Run Details

Duration:
20.2s
Cost:
$0.048625
Provider:
Anthropic

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 hammered against the old mansion windows as Detective Sarah Cole stepped slowly across the creaking wooden floor inside. A single candle flickered upon the marble table where the body of Lord Harrington lay perfectly still and quite cold. His glassy eyes stared toward the ceiling while crimson blood pooled around the silver dagger buried deep within his chest. Detective Cole knelt beside him, her trained eyes scanning every detail of the gruesome scene before quietly drawing her breath. Outside the storm raged louder, yet inside the silence felt heavier than any sound she had ever truly experienced before. Five guests remained trapped within these walls tonight, and one among them had clearly committed this cold, calculated brutal murder. She rose to her feet, turning toward the frightened faces gathered nervously in the doorway of the dimly lit room. Nobody moved, nobody spoke, and every single person there understood the long, terrible night had only just begun for them.
created_at"2026-05-31T11:41:20.509Z" 5/31/2026, 11:41:20 AM
model"anthropic/claude-4.8-opus-20260528"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency3589
moderation_latency(null)
generation_time20155
tokens_prompt46
tokens_completion395
native_tokens_prompt60
native_tokens_completion1933
native_tokens_completion_images(null)
native_tokens_reasoning133
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"
usage0.048625
router(null)
provider_responses
0
endpoint_id"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id"msg_01HG87z8Nu5DhohtfwriJktB"
is_byokfalse
latency1070
model_permaslug"anthropic/claude-4.8-opus-20260528"
provider_name"Anthropic"
status200
user_agent"langchainjs-openai/1.0.0 ((node/v24.16.0; linux; x64))"
http_referer(null)
request_id"req-1780227680-nbliJqTvTyPaSKXLkiPo"
session_id(null)
preset_id(null)
api_type"completions"
id"gen-1780227680-qdpo5a0VgIrMVCVLjnPY"
upstream_id"msg_01HG87z8Nu5DhohtfwriJktB"
total_cost0.048625
cache_discount(null)
upstream_inference_cost0
provider_name"Anthropic"
response_cache_source_id(null)

Evaluation details

Result Evaluator Details Meta Data
100.00% Matches word count n/a
neededCleanfalse
sentences8
wordCounts
020
120
220
320
420
520
620
720