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Run: 2026-05-31-01KSYXK9QSW221DRQDMPXXYQZQ
Run Details
Model:
Claude Opus 4.8 (Reasoning, High)
Test:
Tool usage within Novelcrafter
Scenario:
Create alternate prose sections
Duration:
13.3s
Cost:
$0.021825
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
<nc-section data-title="Chapter 2: A Knight's Welcome" data-color="red"> As I dismounted near the stables, a broad-shouldered figure emerged from the shadows of the hayloft. Sir Roland, his armor dulled by years of honest service, regarded me with steel-grey eyes that had seen a hundred battles. "So you're the new squire," he said, his voice gravelly as crushed stone. He crossed his arms over his scarred breastplate. "I've trained better men than you and buried half of them. Tell me, boy—are you here to learn, or to die a hero's death?" I swallowed hard, gripping Thunder's reins. There was no warmth in his greeting, only the cold weight of expectation. </nc-section> <nc-section data-title="Chapter 2: A Knight's Welcome" data-color="green"> I had barely tied Thunder to the post when a hearty laugh boomed across the courtyard. Sir Roland strode toward me, a giant of a man with a russet beard and a smile that crinkled the corners of his eyes. "Frederick! By the gods, you've your father's look about you!" He clasped my forearm in a grip that nearly buckled my knees. "Come, come—you must be famished after your ride. The cook's prepared a stew that would make a king weep, and I'll not have my new squire fainting before his first lesson." His warmth was infectious, and despite my nerves, I found myself grinning back at him. </nc-section> <nc-section data-title="Chapter 2: A Knight's Welcome" data-color="blue"> The stables smelled of fresh hay and leather as I led Thunder inside. A man knelt in the far stall, gently brushing a chestnut mare, speaking to her in low, soothing tones. "You ride well," he said without turning. "I watched you cross the eastern field. Few squires understand that a horse is a partner, not a tool." He rose slowly, and I saw the quiet dignity in his weathered face. "I am Sir Roland. And you must be Frederick." He extended a calloused hand, his gaze thoughtful and measuring. "We have much to discuss, you and I. But first—let us see your horse properly settled. A knight tends to his mount before himself. Remember that." </nc-section>
created_at
"2026-05-31T11:44:36.615Z"
5/31/2026, 11:44:36 AM
model
"anthropic/claude-4.8-opus-20260528"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2000
moderation_latency
(null)
generation_time
13258
tokens_prompt
318
tokens_completion
576
native_tokens_prompt
435
native_tokens_completion
786
native_tokens_completion_images
(null)
native_tokens_reasoning
34
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
0.021825
router
(null)
provider_responses
0
endpoint_id
"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id
"msg_01TgQyEiUsvxNjxoVnmjea4b"
is_byok
false
latency
898
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-1780227876-QUOok42OWa6AN4k8dSW9"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1780227876-REB3fo8Lk6gRIJU0ZFF5"
upstream_id
"msg_01TgQyEiUsvxNjxoVnmjea4b"
total_cost
0.021825
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