Run: 2026-05-29-01KSSJEWTMB6C41VFZ506R3N0T

Run Details

Duration:
27.8s
Cost:
$0.076100
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 through the creaking rusted iron gate. Inside the dimly lit foyer, a single chandelier flickered weakly above the lifeless body sprawled across the cold marble floor. The victim, wealthy industrialist Marcus Thorne, lay completely motionless with one hand still clutching a torn fragment of yellowed paper. Sarah knelt down beside him, carefully studying the strange symbol drawn in crimson ink across his pale, frozen left cheek. Footsteps echoed somewhere far upstairs, and she suddenly froze, realizing the killer might still be hiding within these shadowed walls. Gripping her flashlight tightly, Sarah slowly rose to her feet and began climbing the grand, creaking staircase toward certain danger.
created_at"2026-05-29T09:53:45.823Z" 5/29/2026, 9:53:45 AM
model"anthropic/claude-4.8-opus-20260528"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency4222
moderation_latency(null)
generation_time27777
tokens_prompt46
tokens_completion414
native_tokens_prompt60
native_tokens_completion3032
native_tokens_completion_images(null)
native_tokens_reasoning207
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"
usage0.0761
router(null)
provider_responses
0
endpoint_id"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id"msg_01YZ5K8vAfaLQkuze75sBAFL"
is_byokfalse
latency2068
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-1780048425-QTjExrOYlOz97gjz2sVi"
session_id(null)
api_type"completions"
id"gen-1780048425-EbBW7VbWsQBfS2eM2ZFR"
upstream_id"msg_01YZ5K8vAfaLQkuze75sBAFL"
total_cost0.0761
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
sentences6
wordCounts
020
120
220
320
420
520