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Run: 2026-09-29-01M3P2BVWWPKAV1N74VDSB644K
Run Details
Model:
Claude Sonnet 5.5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
16.2s
Cost:
$0.020664
Provider:
Claude Platform on AWS
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 the windows of Blackwood Manor as Inspector Halloran stepped over the threshold and shook water from his coat. Somewhere upstairs, a clock struck midnight, and its final chime seemed to hang in the air like a held breath. Lady Verity Blackwood lay sprawled across the library floor, her pearl necklace scattered around her like tiny, lustrous, accusing eyes. Constable Pryce, pale and trembling, met him beside the body and whispered that all windows were bolted from the inside. Halloran knelt, studied the crimson stain blooming across her silk dress, and noticed no weapon lay anywhere in the room. Then he heard it: a faint, deliberate creak from the corridor, proving that someone in this house was still listening. Halloran smiled grimly, buttoned his coat, and resolved that before dawn, someone in Blackwood Manor would tell him the truth.
created_at
"2026-09-29T07:51:44.289Z"
9/29/2026, 7:51:44 AM
model
"anthropic/claude-sonnet-5.5-20260928"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3829
moderation_latency
(null)
generation_time
16161
tokens_prompt
46
tokens_completion
527
native_tokens_prompt
62
native_tokens_completion
2054
native_tokens_completion_images
(null)
native_tokens_reasoning
1751
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
0.020664
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1790668304-BIVnPEy4k8f4qAB9wPEx"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1790668304-DVuHlqlg3hrWrQWeefR0"
upstream_id
"msg_011CfXNEjwx1rPSvoiPeFUQ1"
provider_responses
0
endpoint_id
"99aaad94-923b-4fc1-b763-271ed5486f7a"
id
"msg_011CfXNEjwx1rPSvoiPeFUQ1"
is_byok
false
latency
632
model_permaslug
"anthropic/claude-sonnet-5.5-20260928"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.020664
cache_discount
(null)
upstream_inference_cost
0
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
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