Run: 2026-10-08-01M4DAKQASWA13Z0E39KSRKY9M

Run Details

Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
3.5s
Cost:
$0.000156
Provider:
Claude Platform on AWS

Evaluation summary

Score Evaluator
Details Link
82.72% Matches word count (details)

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 rain fell harder on the silent manor tonight. Detective Morrow stepped through the mansion's creaking oak door. Gaslight flickered across portraits of the family's stern ancestors. Something about the cold foyer felt deeply, unmistakably wrong. Victoria Ashford lay motionless beside the ornate marble fireplace. Her pearl necklace had scattered across the faded Persian carpet. A single crimson droplet marked the edge of her left sleeve. Officer Hale knelt quietly, examining the shattered crystal decanter nearby. "Nobody touched anything," he whispered, avoiding Morrow's steady gaze. Morrow noticed the grandfather clock had stopped at precisely eleven fifteen. Somewhere upstairs, a door slammed shut with a hollow echo. Every suspect in this house had a reason to lie.
created_at"2026-10-08T08:38:22.305Z" 10/8/2026, 8:38:22 AM
model"anthropic/claude-haiku-5.5-20261007"
app_id182717
external_user(null)
streamedtrue
cancelledfalse
latency772
moderation_latency(null)
generation_time3464
tokens_prompt46
tokens_completion198
native_tokens_prompt62
native_tokens_completion300
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)
num_fetches(null)
web_search_engine(null)
origin"https://ncbench.com/"
is_byokfalse
finish_reason"stop"
native_finish_reason"end_turn"
service_tier"default"
usage0.0001562
router(null)
user_agent"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer(null)
request_id"req-1791448702-pO98TYzaLI5nVYPo07Jy"
session_id(null)
preset_id(null)
api_type"completions"
id"gen-1791448702-J5DzlW5pZcvtusyXqqhi"
upstream_id"msg_011CfpU5F1B9GFhyQCrmFJ9w"
provider_responses
0
endpoint_id"b6cdf493-3a61-441f-a134-e7944fddb980"
id"msg_011CfpU5F1B9GFhyQCrmFJ9w"
is_byokfalse
latency772
model_permaslug"anthropic/claude-haiku-5.5-20261007"
provider_name"Claude Platform on AWS"
status200
total_cost0.0001562
cache_discount(null)
upstream_inference_cost0
provider_name"Claude Platform on AWS"
response_cache_source_id(null)
data_region"global"
workspace_id"97e315e5-d303-487d-83c1-83180e8a13d4"

Evaluation details

Result Evaluator Details Meta Data
82.72% Matches word count n/a
neededCleanfalse
sentences12
wordCounts
09
19
29
39
49
510
611
710
89
911
1010
1110