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Run: 2026-05-29-01KSSJVAD5XXRE8KX3T8PQPZAF
Run Details
Model:
Claude Opus 4.8 (Reasoning)
Test:
Tool usage within Novelcrafter
Scenario:
Create alternate prose sections
Duration:
16.7s
Cost:
$0.027150
Provider:
Anthropic
Evaluation summary
Score
Evaluator
Details Link
Pass
Match blue prose section
(details)
Pass
Match green prose section
(details)
Pass
Match red prose section
(details)
no eval
Overall
Model input
System
You are an expert fantasy novel author. You are working on a novel called "The Chronicles of the Last Dragon". The following tools are available to you: - <nc-section> Use this tool to create a new section of prose. Arguments: - "data-title": The title of the section. - "data-color": Any color of (red, green, blue, yellow, purple, orange, pink, brown). Example usage: <nc-section data-title="Chapter 1: The Arrival" data-color="blue"> Frederick, a young squire, arrives at the castle to begin his training. </nc-section>
User/Human
The story so far: <storySoFar> Frederick, a young squire, arrives at the castle to begin his training. </storySoFar>
AI
My horse, a majestic stallion named Thunder, galloped across the open field. The wind whipped through my hair as I rode towards the castle gates. The sun was setting, casting a warm glow over the stone walls. I could see the banners of the kingdom fluttering in the breeze.
User/Human
Continue the story with the following instructions: """The local knight, Sir Roland, greets Frederick near the stables.""" Create 3 alternate prose sections that continue the story. - Version 1 (red) - Version 2 (green) - Version 3 (blue)
Model response
Messages
Meta
AI
I'll create three alternate continuations for this scene. <nc-section data-title="Chapter 1: A Knight's Welcome" data-color="red"> As I dismounted near the stables, the smell of hay and leather filling my nostrils, a towering figure emerged from the shadows. Sir Roland, his armor gleaming faintly in the dying light, strode toward me with the confident gait of a seasoned warrior. A scar traced the line of his jaw, and his eyes held the weight of countless battles. "You must be Frederick," he said, his voice deep and commanding. He clasped my forearm in a firm grip. "I am Sir Roland. The castle has been expecting you. Your father spoke highly of your courage—let us see if the son lives up to the tales." I swallowed hard, suddenly aware of the dust on my travel-worn cloak. "Thank you, Sir Roland. I am ready to begin." He chuckled, a sound like distant thunder. "We shall see, lad. We shall see." </nc-section> <nc-section data-title="Chapter 1: An Unexpected Greeting" data-color="green"> I had barely tied Thunder's reins to the post when a cheerful voice called out from behind a stack of barrels. "Ho there! A new face, by the look of you!" Sir Roland was not at all what I had imagined a knight to be. Round-faced and ruddy-cheeked, he wore a simple tunic rather than armor, and a half-eaten apple in his hand betrayed his casual demeanor. Yet there was a sharpness in his gaze that spoke of hidden depths. "Frederick, isn't it?" he said, tossing me the apple, which I caught clumsily. "The Master-at-Arms told me you'd arrive before nightfall. You've good timing. Supper's nearly ready, and there's much to discuss before your training begins tomorrow." He winked. "But first, let's get that fine horse of yours settled, eh?" </nc-section> <nc-section data-title="Chapter 1: The Measure of a Squire" data-color="blue"> The stable yard was quiet save for the soft nickering of horses. As I led Thunder toward an empty stall, a man stepped into my path—Sir Roland, the knight whose reputation had reached even my distant village. He said nothing at first, only studied me with piercing grey eyes, taking in my posture, my hands, the way I held the reins. The silence stretched until I felt compelled to speak. "I am Frederick, sir. I've come to serve and to learn." A slow nod. "Words are easy, boy. Steel and sweat tell the truth." He gestured to the stall. "Tend to your mount first. A knight who neglects his horse neglects his life. When you've finished, find me in the training yard. Your education begins now—not tomorrow." With that, he turned and walked away, leaving me to wonder what trials awaited. </nc-section>
created_at
"2026-05-29T10:00:32.941Z"
5/29/2026, 10:00:32 AM
model
"anthropic/claude-4.8-opus-20260528"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2057
moderation_latency
(null)
generation_time
16645
tokens_prompt
318
tokens_completion
713
native_tokens_prompt
435
native_tokens_completion
999
native_tokens_completion_images
(null)
native_tokens_reasoning
28
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
0.02715
router
(null)
provider_responses
0
endpoint_id
"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id
"msg_01TqQvSpx8kx3jGWMCU9kPb5"
is_byok
false
latency
973
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-1780048832-kA1cC7wGYCyAgUt3WCQq"
session_id
(null)
api_type
"completions"
id
"gen-1780048832-7wrU9fb71GDkFBsB6SKh"
upstream_id
"msg_01TqQvSpx8kx3jGWMCU9kPb5"
total_cost
0.02715
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
response_cache_source_id
(null)
Evaluation details
Result
Evaluator
Details
Meta Data
Pass
Match blue prose section
/<nc-section data-title="[^"]*" data-color="blue">[^<]+<\/nc-section>/
n/a
Pass
Match green prose section
/<nc-section data-title="[^"]*" data-color="green">[^<]+<\/nc-section>/
n/a
Pass
Match red prose section
/<nc-section data-title="[^"]*" data-color="red">[^<]+<\/nc-section>/
n/a
no eval