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Run: 2026-10-08-01M4DAMT4A46YDM1XR7T7B052D
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Medium)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
3.5s
Cost:
$0.000187
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
84.45%
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
The rain fell hard against the windows of Blackmoor Manor. Inspector Halloway arrived just after midnight with his weary assistant. Lord Ashcombe had been found dead in the library that evening. Nobody in the household had heard a single scream or cry. The fireplace still glowed faintly with embers from the previous night. Every door in the mansion had been locked from the inside. Mrs. Whitlow, the housekeeper, wrung her trembling hands repeatedly. Her nephew Edmund stood quietly near the staircase, saying nothing. Lady Ashcombe sat rigidly upon the velvet settee, staring ahead. Halloway knelt beside the body and studied the pale, twisted fingers. A crystal decanter lay shattered upon the Persian rug nearby. Something glinted beneath the leather armchair, catching the lamplight. He reached for it carefully, aware that everyone was watching him. It was a silver cufflink, engraved with a single initial: M. Across the room, Edmund's face drained of all remaining color.
created_at
"2026-10-08T08:38:57.939Z"
10/8/2026, 8:38:57 AM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3416
moderation_latency
(null)
generation_time
3416
tokens_prompt
46
tokens_completion
249
native_tokens_prompt
62
native_tokens_completion
361
native_tokens_completion_images
(null)
native_tokens_reasoning
0
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
0.0001867
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791448737-SjN0lYgBHI1bYJHULAXl"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791448737-uhgO76r3FONP88IKZBap"
upstream_id
"msg_011CfpU7sukBD8V4QHn9b2aG"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpU7sukBD8V4QHn9b2aG"
is_byok
false
latency
976
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0001867
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
84.45%
Matches word count
n/a
neededClean
false
sentences
15
wordCounts
0
10
1
10
2
11
3
11
4
11
5
11
6
9
7
10
8
10
9
11
10
10
11
9
12
11
13
11
14
10