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Run: 2026-10-08-01M4DYY7J0FEYPMDK4PZP6DFZH
Run Details
Model:
Claude Haiku 5.5 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
4.4s
Cost:
$0.000275
Provider:
Claude Platform on AWS
Evaluation summary
Score
Evaluator
Details Link
87.04%
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 hammered against the mansion windows that November night. Detective Eleanor Vance stepped carefully across the wet gravel driveway. Nobody in the village had expected trouble at Blackwood Manor ever. Her flashlight beam swept over the ivy-covered stone steps ahead. Officer Thomas Reed waited beside the iron gate, collar turned up. "The body's inside, in the library," he said quietly. Eleanor nodded, though her stomach tightened with unwelcome dread. The heavy oak door stood slightly ajar, creaking in the wind. She pushed it open and stepped into the dim foyer. A grandfather clock ticked somewhere, marking each passing second relentlessly. Dust motes drifted through the thin beam of her light. Thomas followed close behind, his boots echoing on marble tiles. They passed a portrait of Lord Alistair Blackwood, stern and watchful. Its painted eyes seemed to follow them toward the library. At the threshold, Eleanor paused and studied the scene carefully. Lord Blackwood lay slumped across his mahogany desk, motionless. A single silver letter opener protruded from beneath his left shoulder. Beside him, an overturned teacup had stained the expensive Persian rug. "Who found him?" Eleanor asked, not taking her eyes away. "His wife, Margaret," Thomas replied, glancing toward the staircase. Eleanor knelt beside the desk and noticed something peculiar immediately. The ink bottle was open, yet the desk held no letters.
created_at
"2026-10-08T14:33:38.123Z"
10/8/2026, 2:33:38 PM
model
"anthropic/claude-haiku-5.5-20261007"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4334
moderation_latency
(null)
generation_time
4334
tokens_prompt
46
tokens_completion
365
native_tokens_prompt
62
native_tokens_completion
537
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
0.0002747
router
(null)
user_agent
"langchainjs-openai/1.0.0 ((node/v24.21.0; linux; x64))"
http_referer
(null)
request_id
"req-1791470018-a6TtwWwT1HeBDTpov83h"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1791470018-QaNFLPHocyglqVR6Zxzm"
upstream_id
"msg_011CfpwAXUu17VMzaxwHLwbq"
provider_responses
0
endpoint_id
"b6cdf493-3a61-441f-a134-e7944fddb980"
id
"msg_011CfpwAXUu17VMzaxwHLwbq"
is_byok
false
latency
893
model_permaslug
"anthropic/claude-haiku-5.5-20261007"
provider_name
"Claude Platform on AWS"
status
200
total_cost
0.0002747
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
87.04%
Matches word count
n/a
neededClean
false
sentences
22
wordCounts
0
10
1
10
2
11
3
10
4
11
5
9
6
9
7
11
8
10
9
10
10
10
11
10
12
11
13
10
14
10
15
9
16
11
17
11
18
10
19
9
20
10
21
11