NC Bench
Overview
About
Tests
Categories
Models
Vendors
Compare
Run: 2026-07-25-01KYCR9GXV5339HW7NFE87TXBD
Run Details
Model:
Claude Opus 5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
19.9s
Cost:
$0.044175
Provider:
Amazon Bedrock
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 10 words. Please make sure that each sentence has the same length. Only return the opening itself.
Model response
Messages
Meta
AI
Rain hammered the slate roof of Ashcombe Hall all night. By dawn the storm had passed, leaving the gardens drowned. Mrs. Pell found the library door locked from the inside. She knocked twice, then a third time, calling his name. Nothing answered her but the tall clock in the corridor. The gardener came with tools and forced the brass lock. Wood splintered, hinges groaned, and the heavy door swung inward. Sir Edmund Ashcombe sat upright in his tall leather chair. His fountain pen rested neatly beside an unfinished letter, uncapped. A single red thread of blood crossed his starched collar. The windows were latched, the chimney cold, the curtains undisturbed. Footprints, dried to grey mud, led away from the desk. They stopped halfway across the room and simply went nowhere. Mrs. Pell screamed once and then grew terribly, carefully quiet. The gardener stared at the carpet and said one word. Murder, he whispered, though nobody else had used that word. Outside, church bells counted seven over the drowned rose beds.
created_at
"2026-07-25T13:44:02.755Z"
7/25/2026, 1:44:02 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4407
moderation_latency
(null)
generation_time
19835
tokens_prompt
46
tokens_completion
570
native_tokens_prompt
60
native_tokens_completion
1755
native_tokens_completion_images
(null)
native_tokens_reasoning
312
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
"end_turn"
service_tier
"default"
usage
0.044175
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsiYckQNAN42o6Gwr1h"
is_byok
false
latency
1570
model_permaslug
"anthropic/claude-opus-5-20260723"
provider_name
"Amazon Bedrock"
status
200
user_agent
"langchainjs-openai/1.0.0 ((node/v24.18.0; linux; x64))"
http_referer
(null)
request_id
"req-1784987042-XjoQGOBfVIVz9N3wesDj"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784987042-xBgGi5kUJ7rgrPJ4GPAc"
upstream_id
"msg_011CdNsiYckQNAN42o6Gwr1h"
total_cost
0.044175
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
response_cache_source_id
(null)
data_region
"global"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
17
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10
10
10
11
10
12
10
13
10
14
10
15
10
16
10