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Run: 2026-10-08-01M4D9W8M9J8HB499J2BP0V8C0
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
8.8s
Cost:
$0.000976
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
The rain had not stopped for three days when Inspector Helen Marsh reached Blackwood Manor, its gates hanging wide open. Inside the hall, the butler, Mr. Pryce, stood frozen beside the grand staircase, his hands trembling and his face ashen. Lord Edmund Blackwood lay sprawled across the Persian rug in the library, a silver letter opener protruding from his chest. Marsh knelt beside the body, noting the dried blood, the overturned chair, and the single muddy footprint near the window. Nothing about the scene felt rushed or careless, which unsettled her far more than the corpse itself ever could possibly. Somewhere above them, a door creaked open, and a voice whispered that the killer had not yet left the house.
created_at
"2026-10-08T08:25:33.751Z"
10/8/2026, 8:25:33 AM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2364
moderation_latency
(null)
generation_time
8551
tokens_prompt
46
tokens_completion
370
native_tokens_prompt
62
native_tokens_completion
1940
native_tokens_completion_images
(null)
native_tokens_reasoning
1685
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
0.0009762
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791447933-wTlPuj2UZq1pgtJ2KvSg"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791447933-cr7BqzTFZg44uLNCLtWL"
upstream_id
"msg_011CfpT6bDG4NZDX4VpwtdzH"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpT6bDG4NZDX4VpwtdzH"
is_byok
false
latency
757
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0009762
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
6
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20