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Run: 2026-05-31-01KSYX9S0S2M65GWE0CX38YDHC
Run Details
Model:
Claude Opus 4.8 (Reasoning, High)
Test:
Tool usage within Novelcrafter
Scenario:
Create alternate prose sections
Duration:
15.6s
Cost:
$0.025150
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 moment in the story. <nc-section data-title="Version 1: A Warrior's Welcome" data-color="red"> As I dismounted near the stables, a broad-shouldered man strode toward me, his armor gleaming in the dying light. Sir Roland, the realm's most renowned knight, regarded me with steel-grey eyes that seemed to measure my very soul. "So you're the squire they sent me," he said, his voice rough as gravel. He gripped my forearm in a warrior's clasp, his strength nearly buckling my knees. "I'll not coddle you, boy. The road ahead will break weaker men than you. But if you survive my training, you'll be forged into something the kingdom has not seen in a generation." I swallowed hard, meeting his gaze. There was no warmth in his welcome—only the promise of trials to come. </nc-section> <nc-section data-title="Version 2: An Unexpected Kindness" data-color="green"> I had barely tied Thunder to a post when a gentle voice called out from the shadows of the stables. "You must be Frederick. We've been expecting you." Sir Roland emerged, not the towering figure I had imagined, but a man with kind eyes and an easy smile. He helped me with my saddlebags without a word of complaint, treating me less like a servant and more like a guest. "Travel weary, no doubt," he said, clapping me warmly on the shoulder. "Come, there's hot stew waiting, and we'll get your horse settled. Training begins tomorrow, but tonight, you rest. A man learns nothing on an empty stomach and a tired mind." Something in his manner put me instantly at ease. Perhaps this place would feel like home after all. </nc-section> <nc-section data-title="Version 3: A Mysterious Encounter" data-color="blue"> The stables were quiet save for the soft nickering of horses. As I led Thunder inside, a figure stepped from the darkness, and I nearly drew my dagger before I recognized the crest upon his cloak. "Frederick." Sir Roland spoke my name as though it carried some hidden weight. His face was etched with worry lines, and he glanced over his shoulder before continuing in a hushed tone. "You arrive at a strange hour, lad. Things are not as they seem within these walls." He pressed something cold into my palm—an iron token bearing the image of a dragon. "Tell no one I gave you this. And whatever you hear in the coming days, trust only what you see with your own eyes." He vanished as quickly as he had appeared, leaving me clutching the mysterious token and questioning everything I thought I knew about my new home. </nc-section>
created_at
"2026-05-31T11:39:24.582Z"
5/31/2026, 11:39:24 AM
model
"anthropic/claude-4.8-opus-20260528"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2157
moderation_latency
(null)
generation_time
15550
tokens_prompt
318
tokens_completion
699
native_tokens_prompt
435
native_tokens_completion
919
native_tokens_completion_images
(null)
native_tokens_reasoning
33
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
0.02515
router
(null)
provider_responses
0
endpoint_id
"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id
"msg_016ejFeLALLe1fpXwf21peFz"
is_byok
false
latency
951
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-1780227564-WO5eN3MT75K5lh1jSBfk"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1780227564-4PwcfvuFyGbWeSO7tSS6"
upstream_id
"msg_016ejFeLALLe1fpXwf21peFz"
total_cost
0.02515
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