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Run: 2026-07-25-01KYCQY4FAXGHPC8Y7VAG3PMZ5
Run Details
Model:
Claude Opus 5 (Reasoning)
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
38.3s
Cost:
$0.091900
Provider:
Amazon Bedrock
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 been falling on Ashgrove Manor since midnight, and now the gravel driveway shone like freshly polished obsidian. Inspector Vera Lund parked her car beneath the dripping yews and waited one long, deliberate moment before opening the door. Three constables stood on the terrace, hunched inside their coats, pretending that the weather was the worst thing about tonight. The body lay in the library, they told her, and nobody had touched anything since the first scream after eleven. Vera doubted that; people always touched things, then lied about it with the wholly sincere faces of badly frightened children. Inside, the house smelled of woodsmoke, wet wool, and that particular sourness which fear always leaves behind in crowded rooms. Nine guests waited in the drawing room, gathered around the fire like figures inside some badly composed old oil painting. One of them had killed Sir Edmund Ashgrove, and one of them would be the first person to say so. Vera unbuttoned her wet coat, took out her notebook, and asked very quietly who exactly had discovered the dead man. Eight of them looked at the ninth, whose hands shook so badly that her teacup rattled against its china saucer.
created_at
"2026-07-25T13:37:49.553Z"
7/25/2026, 1:37:49 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
4953
moderation_latency
(null)
generation_time
38210
tokens_prompt
46
tokens_completion
840
native_tokens_prompt
60
native_tokens_completion
3664
native_tokens_completion_images
(null)
native_tokens_reasoning
540
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
0.0919
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNsF1cBb2vJR6Ymfi2aC"
is_byok
false
latency
1698
model_permaslug
"anthropic/claude-opus-5-20260723"
provider_name
"Amazon Bedrock"
status
200
user_agent
"langchainjs-openai/1.0.0 ((node/v24.18.0; linux; x64))"
http_referer
(null)
request_id
"req-1784986669-dRkr4wMwl6PvtSRwYKNY"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784986669-pJn2NsEXl8ktmA0IHb2p"
upstream_id
"msg_011CdNsF1cBb2vJR6Ymfi2aC"
total_cost
0.0919
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Amazon Bedrock"
response_cache_source_id
(null)
data_region
"global"
Evaluation details
Result
Evaluator
Details
Meta Data
100.00%
Matches word count
n/a
neededClean
false
sentences
10
wordCounts
0
20
1
20
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20