Run: 2026-04-24-01KQ0MV6GDJADNZ6SMGMA8GHJH

Run Details

Duration:
17.6s
Cost:
$0.028855
Provider:
OpenAI

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
At midnight, the bell above Blackthorn Manor's library door rang once, though everyone swore the house was empty that night. Inspector Vale found Lord Ashcombe seated beside the cold hearth, a silver letter opener buried beneath his ribs at dawn. Rain crawled down the tall windows, blurring the gardens where fresh footprints vanished into the yew maze before sunrise entirely. On the desk lay five teacups, four still warm, and one stained dark with bitter almond poison around its rim. His widow stood in the doorway without tears, twisting a pearl necklace until the clasp snapped open in her hands. Behind her, the nephew laughed too loudly, while the governess watched him with a face like thin paper in candlelight. Vale noticed mud on the Persian rug, smelling faintly of river silt and crushed greenhouse lilies near the corpse alone. Then the dead man's pocket watch chimed thirteen times, and someone upstairs began to scream his name again and again.
created_at"2026-04-24T21:03:01.654Z" 4/24/2026, 9:03:01 PM
model"openai/gpt-5.5-20260423"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency16189
moderation_latency(null)
generation_time17509
tokens_prompt46
tokens_completion253
native_tokens_prompt41
native_tokens_completion955
native_tokens_completion_images0
native_tokens_reasoning756
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"completed"
usage0.028855
router(null)
provider_responses
0
endpoint_id"58e5b336-423e-430b-a2ab-8bc353f0c51b"
id"resp_0508d58ff1d7e14a0169ebda85baf88196861d1893bea263be"
is_byokfalse
latency313
model_permaslug"openai/gpt-5.5-20260423"
provider_name"OpenAI"
status200
user_agent"langchainjs-openai/1.0.0 ((node/v24.14.1; linux; x64))"
http_referer(null)
request_id"req-1777064581-xTa9gz2SwJKdSHSDudHj"
session_id(null)
api_type"completions"
id"gen-1777064581-NtouPYpICCQK2AMIxRxy"
upstream_id"resp_0508d58ff1d7e14a0169ebda85baf88196861d1893bea263be"
total_cost0.028855
cache_discount(null)
upstream_inference_cost0
provider_name"OpenAI"
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