NC Bench
Overview
About
Tests
Categories
Models
Vendors
Compare
Run: 2026-04-24-01KQ0NCQQQCYXF8NB7Y8E8XEKJ
Run Details
Model:
GPT-5.5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
13.9s
Cost:
$0.026125
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
Messages
Meta
AI
Rain hammered Blackthorn Manor as Inspector Vale arrived, finding every window lit and every servant whispering behind gloved hands nervously. In the library, Lord Ashcombe lay beneath the chandelier, a crimson letter opener buried deep in his throat, still gleaming. His daughter Eleanor stood beside the fireplace, dry-eyed, while her pearl necklace trembled against her black dress in candlelight nearby. The butler claimed the doors were locked, though muddy footprints crossed the Persian rug toward the terrace and vanished outside. Vale noticed a half-burned photograph curling in the grate, showing Ashcombe with a woman nobody named or dared remember aloud. Before anyone could speak, the grandfather clock struck midnight, and somewhere upstairs a young man screamed once, then fell silent. Vale closed the library door, pocketed the only key, and asked who had wished Lord Ashcombe dead so badly tonight.
created_at
"2026-04-24T21:12:36.351Z"
4/24/2026, 9:12:36 PM
model
"openai/gpt-5.5-20260423"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
12538
moderation_latency
(null)
generation_time
13627
tokens_prompt
46
tokens_completion
240
native_tokens_prompt
41
native_tokens_completion
864
native_tokens_completion_images
0
native_tokens_reasoning
682
native_tokens_cached
0
num_media_prompt
(null)
num_input_audio_prompt
(null)
num_media_completion
0
num_search_results
(null)
num_fetches
(null)
web_search_engine
(null)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"completed"
usage
0.026125
router
(null)
provider_responses
0
endpoint_id
"58e5b336-423e-430b-a2ab-8bc353f0c51b"
id
"resp_02d0d4254c4719890169ebdcc475fc8190b52c7092b8d79970"
is_byok
false
latency
297
model_permaslug
"openai/gpt-5.5-20260423"
provider_name
"OpenAI"
status
200
user_agent
"langchainjs-openai/1.0.0 ((node/v24.14.1; linux; x64))"
http_referer
(null)
request_id
"req-1777065156-cOc3ph2O2gSNCoHe0bXu"
session_id
(null)
api_type
"completions"
id
"gen-1777065156-A4Fg7o2iKxuFMRvvb7kX"
upstream_id
"resp_02d0d4254c4719890169ebdcc475fc8190b52c7092b8d79970"
total_cost
0.026125
cache_discount
(null)
upstream_inference_cost
0
provider_name
"OpenAI"
response_cache_source_id
(null)
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
7
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20