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Run: 2026-06-01-01KT1J3BE30PRQR9G0DMWFD84R
Run Details
Model:
Claude Opus 4.8 (Reasoning, Low)
Test:
N-Length Sentences
Scenario:
Write sentences with 10 words each
Duration:
35.4s
Cost:
$0.027275
Provider:
Anthropic
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 old mansion windows throughout the stormy night. Detective Sarah Cole arrived just after the clock struck midnight. The butler opened the heavy door with trembling pale hands. Inside, a single body lay sprawled across the cold floor. Lord Pemberton, wealthy and feared, would never speak again now. Five guests gathered nervously inside the dimly lit grand parlor. Each one harbored secrets worth killing for, Sarah quietly suspected. She studied every anxious face searching for hidden silent guilt. Outside, the storm raged louder, trapping everyone within these walls. Tonight, someone among them was a cold, calculating, ruthless killer.
created_at
"2026-06-01T12:21:23.02Z"
6/1/2026, 12:21:23 PM
model
"anthropic/claude-4.8-opus-20260528"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
3484
moderation_latency
(null)
generation_time
35404
tokens_prompt
46
tokens_completion
267
native_tokens_prompt
60
native_tokens_completion
1079
native_tokens_completion_images
(null)
native_tokens_reasoning
102
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
0.027275
router
(null)
provider_responses
0
endpoint_id
"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id
"msg_01BfxWM21tZ6ERYNrGEEottx"
is_byok
false
latency
929
model_permaslug
"anthropic/claude-4.8-opus-20260528"
provider_name
"Anthropic"
status
200
user_agent
"langchainjs-openai/1.0.0 ((node/v24.16.0; linux; x64))"
http_referer
(null)
request_id
"req-1780316483-pVXga5afDv3axgrlOTeE"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1780316483-3q6Oar6tFJPUwEewWcBI"
upstream_id
"msg_01BfxWM21tZ6ERYNrGEEottx"
total_cost
0.027275
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
response_cache_source_id
(null)
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
10
1
10
2
10
3
10
4
10
5
10
6
10
7
10
8
10
9
10