Run: 2026-06-01-01KT1GEDZAP00J8PDNK9STCD6Y

Run Details

Duration:
29.9s
Cost:
$0.081525
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 carefully across the creaking, rotting wooden floorboards. A single oil lamp flickered weakly in the corner, casting long, eerie shadows over the cold body near the fireplace. Lord Pemberton lay sprawled and motionless, his glassy eyes wide open, a crimson stain spreading across his white evening shirt. Sarah knelt beside him, pressing two fingers against his neck, though she already knew the terrible truth about this night. Outside, thunder rumbled ominously while seven frightened guests waited upstairs, unaware that one of them was certainly a cold killer. She rose slowly, scanning the dim room for clues, noting the shattered wine glass beside the victim's outstretched right hand.
created_at"2026-06-01T11:52:28.911Z" 6/1/2026, 11:52:28 AM
model"anthropic/claude-4.8-opus-20260528"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency3660
moderation_latency(null)
generation_time29852
tokens_prompt46
tokens_completion437
native_tokens_prompt60
native_tokens_completion3249
native_tokens_completion_images(null)
native_tokens_reasoning235
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"
usage0.081525
router(null)
provider_responses
0
endpoint_id"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id"msg_01BAyZovgD5pakU2TVwpoUqH"
is_byokfalse
latency944
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-1780314748-OVAp9zxENkxclgkFZzQt"
session_id(null)
preset_id(null)
api_type"completions"
id"gen-1780314748-8F4AFNWIbllPYJkpu3kG"
upstream_id"msg_01BAyZovgD5pakU2TVwpoUqH"
total_cost0.081525
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