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Run: 2026-06-01-01KT1G0EKM4JB8NT57EZS0AZSM
Run Details
Model:
Claude Opus 4.8 (Reasoning, Low)
Test:
Tool usage within Novelcrafter
Scenario:
Create alternate prose sections
Duration:
16.3s
Cost:
$0.026500
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="Version 1: A Stern Welcome" data-color="red"> As I dismounted, a broad-shouldered man strode toward me from the stables, his armor catching the dying light. Sir Roland was every inch the knight the songs described—a jagged scar traced his cheek, and his eyes held the weariness of a hundred battles. "So you're the new squire," he said, his voice gravel and iron. He looked me over, unimpressed. "You're smaller than I expected. The training yard will either break you or make you. Pray it's the latter, boy." He turned without another word, gesturing for me to follow. I gathered Thunder's reins and hurried after him, my heart pounding. Whatever I had imagined of this place, the reality already felt sharper, colder, and far more real. </nc-section> <nc-section data-title="Version 2: An Unexpected Kindness" data-color="green"> A man emerged from the stables, wiping hay from his hands. He was older than I'd imagined a knight to be, with silver threading his dark beard and a warmth in his eyes that surprised me. "You must be Frederick," he said, a genuine smile spreading across his weathered face. "I'm Sir Roland. We've been expecting you." He reached out and clapped a firm hand on my shoulder. "That's a fine horse you've got there. Treat him well and he'll carry you through worse than you can imagine." He took Thunder's reins gently, stroking the stallion's neck. "Come. You've ridden far, and there's stew on the fire. The training can wait until your belly's full and your bones have rested. A knight learns nothing on an empty stomach." For the first time since leaving home, I felt the knot in my chest begin to loosen. </nc-section> <nc-section data-title="Version 3: A Mysterious Encounter" data-color="blue"> I had barely slid from the saddle when a voice cut through the gathering dusk. "You ride as though something pursues you." I spun to find a tall figure leaning against the stable doorway, half-hidden in shadow. Sir Roland stepped into the light, and I saw that his gaze was fixed not on me, but on the darkening horizon beyond the castle walls. "Strange times brought you here, Frederick," he murmured. "Stranger times still await us all." His hand rested on the pommel of his sword, and a flicker of something—fear, perhaps, or premonition—crossed his face. "Have you heard the whispers from the north? The old fires stirring in the mountains?" I shook my head, suddenly aware of a chill that had nothing to do with the wind. "No," he said softly. "I suppose you wouldn't have. But you will, lad. You will." He finally met my eyes. "Come. There is much you must learn, and I fear we have precious little time." </nc-section>
created_at
"2026-06-01T11:44:51.017Z"
6/1/2026, 11:44:51 AM
model
"anthropic/claude-4.8-opus-20260528"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2128
moderation_latency
133
generation_time
15937
tokens_prompt
318
tokens_completion
757
native_tokens_prompt
435
native_tokens_completion
973
native_tokens_completion_images
(null)
native_tokens_reasoning
43
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
0.0265
router
(null)
provider_responses
0
endpoint_id
"b0d3beaa-5ff7-4666-a749-b1bb2b14c916"
id
"msg_016jYxVe5ea6DPez9FAqqoZW"
is_byok
false
latency
1127
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-1780314291-SEHOVmSp14iuKivM8vuF"
session_id
(null)
preset_id
(null)
api_type
"completions"
id
"gen-1780314291-3fTXZG30fPXIOroT4yDt"
upstream_id
"msg_016jYxVe5ea6DPez9FAqqoZW"
total_cost
0.0265
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