Run: 2026-05-31-01KSYX8107H6E02M7NTW6HM4W1

Run Details

Duration:
29.7s
Cost:
$0.081750
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 hammered against the old manor windows as Detective Sarah Morgan stepped carefully across the creaking wooden floor. A single lifeless body lay sprawled before the grand fireplace, blood pooling slowly beneath the cold form of Lord Ashworth. His wide eyes stared blankly toward the high ceiling, frozen forever in an expression of pure, unmistakable terror and disbelief. Sarah crouched down beside the victim, carefully noting the silver letter opener buried deep within his chest, glinting in firelight. Behind her, the six remaining guests huddled together in nervous silence, each harboring secrets that might explain this brutal crime. Outside, the violent storm raged even louder, trapping everyone inside the isolated old estate until morning brought answers and justice.
created_at"2026-05-31T11:38:27.437Z" 5/31/2026, 11:38:27 AM
model"anthropic/claude-4.8-opus-20260528"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency3670
moderation_latency(null)
generation_time29079
tokens_prompt46
tokens_completion407
native_tokens_prompt60
native_tokens_completion3258
native_tokens_completion_images(null)
native_tokens_reasoning209
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"
usage0.08175
router(null)
provider_responses
0
endpoint_id"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id"msg_013qn7Rz73bY4ZkYoyUq3Sro"
is_byokfalse
latency1089
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-1780227507-35gxWoO5jPpEpURsUOoK"
session_id(null)
preset_id(null)
api_type"completions"
id"gen-1780227507-edmtU2Azq6tS6oCeC1co"
upstream_id"msg_013qn7Rz73bY4ZkYoyUq3Sro"
total_cost0.08175
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