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Run: 2026-07-25-01KYCPP51TSJW5N0FV95GZVE0J
Run Details
Model:
Claude Opus 5
Test:
N-Length Sentences
Scenario:
Write sentences with 20 words each
Duration:
10.4s
Cost:
$0.010975
Provider:
Amazon Bedrock
Evaluation summary
Score
Evaluator
Details Link
96.42%
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 since midnight, and by dawn the gravel drive outside Thornfield House was a shallow river. Inspector Margaret Voss parked her car beside the fountain, noting that three other vehicles already sat there, engines cold. The front door stood open six inches, which the housekeeper swore she had locked herself at eleven the previous evening. Inside, the marble floor held a single wet footprint pointing toward the library, too small to belong to any man. Voss followed it past the grandfather clock, which had stopped at two-seventeen, its brass pendulum hanging perfectly still and silent. In the library, Sir Alistair Crane sat upright in his leather chair, eyes open, a chess piece clutched in hand. The white queen, carved from ivory, had been pressed so hard into his palm that the skin had broken slightly. No wound was visible anywhere, no blood, no bruising, nothing at all to suggest how the old man had died. Behind Voss, someone cleared their throat, and she turned to find four faces watching her from the doorway, unmoving, waiting. "None of us touched him," said the tallest, a woman in riding boots still caked with mud from the garden. Voss said nothing, because she had already counted the chess board and found that two other pieces were also missing.
created_at
"2026-07-25T13:15:59.425Z"
7/25/2026, 1:15:59 PM
model
"anthropic/claude-opus-5-20260723"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2573
moderation_latency
(null)
generation_time
10306
tokens_prompt
46
tokens_completion
331
native_tokens_prompt
60
native_tokens_completion
427
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
0.010975
router
(null)
provider_responses
0
endpoint_id
"76cb4608-f48c-483d-8da8-9957fb44244e"
id
"msg_011CdNqaS9cDSXWKnr4Y3rph"
is_byok
false
latency
2569
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-1784985359-P8NgM4LnD2zqHmOd1ry3"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1784985359-AxZztDzhcesjAoQrhb2y"
upstream_id
"msg_011CdNqaS9cDSXWKnr4Y3rph"
total_cost
0.010975
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
96.42%
Matches word count
n/a
neededClean
false
sentences
11
wordCounts
0
20
1
19
2
20
3
20
4
20
5
20
6
20
7
20
8
20
9
20
10
20