Model

Claude Opus 4.6

Test

N-Length Sentences

Scenario

Write sentences with 10 words each

Run ID

2026-02-08-01KGYWZQA0TAPRD6PH4CV3DGH3

Model input

User/Human
Please write the opening scene of a murder mystery where each sentence has exactly 10 words. Please make sure that each sentence has the same length. Only return the opening itself.

Model response

AI
The old mansion stood silently at the end of town. Detective Morgan arrived just as the clock struck midnight sharp. Rain poured down heavily, soaking the gravel path leading inside. A single light flickered behind the curtain on floor two. The butler opened the door with trembling hands and spoke. "Sir, the master of the house is dead," he said. Morgan stepped inside and noticed muddy footprints on the floor. The chandelier above cast long shadows across the grand hallway. A broken wine glass lay shattered near the spiral staircase. Upstairs, the body of Lord Ashworth waited in cold silence.
created_at"2026-02-08T15:12:45.969327+00:00" Sunday, February 8th, 2026 at 3:12:45 PM GMT+00:00
model"anthropic/claude-4.6-opus-20260205" 
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency2432
moderation_latency(null)
generation_time6654
tokens_prompt35
tokens_completion120
native_tokens_prompt44
native_tokens_completion146
native_tokens_completion_images(null)
native_tokens_reasoning0
native_tokens_cached0
num_media_prompt(null)
num_input_audio_prompt(null)
num_media_completion0
num_search_results(null)
origin"https://ncbench.com/" 
is_byokfalse
finish_reason"stop" 
native_finish_reason"stop" 
usage0.00387
router(null)
provider_responses
0
id"msg_01VXsrxcW32GRzepoCFuw2T2" 
status200
is_byokfalse
latency2432
endpoint_id"c926c048-563e-44b0-8434-95965bee924c" 
provider_name"Anthropic" 
model_permaslug"anthropic/claude-4.6-opus-20260205" 
api_type"completions" 
id"gen-1770563558-LIya5lxIK8K0TCjAfIva" 
upstream_id"msg_01VXsrxcW32GRzepoCFuw2T2" 
total_cost0.00387
cache_discount(null)
upstream_inference_cost0
provider_name"Anthropic" 

Evaluation details

Result Evaluator Details Meta Data
100.0000% Matches word count n/a
neededCleanfalse
sentences10
wordCounts
010
110
210
310
410
510
610
710
810
910