Run: 2026-05-29-01KSSJXSWJWXR53KMJJ83PE7YE

Run Details

Duration:
17.5s
Cost:
$0.046550
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 cold rain fell hard against the old mansion windows, washing away the dark secrets that lived inside its walls. Detective Sarah Morgan stepped slowly through the heavy front door, her flashlight cutting across the silent, shadowed grand entrance hall. On the cold marble floor lay a man, his eyes wide open, a crimson stain spreading beneath his crumpled body. She knelt down beside the victim carefully, noting the broken glass, the spilled wine, and the single muddy footprint nearby. Upstairs, a single floorboard creaked softly, reminding her that someone else still lurked within this house of buried, deadly lies.
created_at"2026-05-29T10:01:54.33Z" 5/29/2026, 10:01:54 AM
model"anthropic/claude-4.8-opus-20260528"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency3649
moderation_latency(null)
generation_time17464
tokens_prompt46
tokens_completion294
native_tokens_prompt60
native_tokens_completion1850
native_tokens_completion_images(null)
native_tokens_reasoning131
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"
usage0.04655
router(null)
provider_responses
0
endpoint_id"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id"msg_01H71KD45URUYE8vohXoQNqC"
is_byokfalse
latency1098
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-1780048914-hQVDdaaY1L2x7yXWt9hA"
session_id(null)
api_type"completions"
id"gen-1780048914-9kgtipjppZtiaBe0mxB0"
upstream_id"msg_01H71KD45URUYE8vohXoQNqC"
total_cost0.04655
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
sentences5
wordCounts
020
120
220
320
420