NC Bench
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Run: 2026-02-17-01KHMR9EPV5NHN681GWT62XP0Y
Run Details
Model:
Claude Opus 4.5
Test:
Bad Writing Habits
Scenario:
Fantasy: entering an ancient ruin
Duration:
51.3s
Cost:
$0.059135
Provider:
Anthropic
Model input
System
You are an expert novelist with a gift for vivid, immersive prose. You write in tight third-person limited point of view with a strong narrative voice. Your prose is clean, precise, and engaging — you favor strong verbs, concrete details, and natural-sounding dialogue. You will be given a story bible (codex) containing canonical details about characters, locations, items, and lore. Use these details to ground your writing in the established world. Stay consistent with the codex. Write only the prose of the scene. Do not include titles, chapter headings, markdown formatting, or any commentary before or after the scene.
User/Human
<codex> <character id="4412" name="Aurora Carter" aliases="Rory, Laila, Aurora, Carter, Malphora" pronouns="she/her" species="Human" storyRole="Protagonist"> <eyeColor>bright blue</eyeColor> <hair>straight shoulder-length black</hair> <height>5'6"</height> <age>25</age> <scar>small crescent-shaped scar on her left wrist from a childhood accident</scar> <description>Aurora, referred to by her friends as Rory, is cool-headed, intelligent, and known for quick out-of-the-box thinking.</description> <backstory>Born in Cardiff to an Irish barrister father (Brendan Carter) and Welsh teacher mother (Jennifer Carter née Ellis), Rory reluctantly pursued Pre-Law at Cardiff University. She fled to London at the behest of her childhood friend Eva after leaving an abusive ex named Evan. By day, Rory works part-time as a delivery person for Yu-Fei Cheung's Golden Empress restaurant. She lives in a flat above Silas' bar.</backstory> </character> <character id="4418" name="Nyx" aliases="Nyx, the Shadow, Nightwhisper" pronouns="they/them" species="Shade" storyRole="Wild Card"> <eyeColor>faintly glowing violet</eyeColor> <height>approximately 6'2" in solid form</height> <age>ageless</age> <form>humanoid silhouette of living shadow, can shift between solid and incorporeal</form> <voice>sounds like a whisper carried on the wind</voice> <description>A being of living shadow, existing between the mortal plane and the spaces between realms.</description> <backstory>Nyx was once a human sorcerer named Aldric who became trapped between realms during a failed summoning ritual in 1643. They now exist as a Shade, bound to the mortal plane but able to slip between shadows.</backstory> </character> <character id="4424" name="Isolde Varga" aliases="Isolde, the Seer" pronouns="she/her" species="Half-Fae" storyRole="Oracle"> <eyeColor>pale lavender</eyeColor> <hair>silver, reaching her waist</hair> <height>5'5"</height> <age>300 years old</age> <appearance>ethereal, ageless</appearance> <speech>speaks in riddles</speech> <footprints>leaves no footprints when she walks</footprints> <compulsion>cannot lie (Fae compulsion) but can mislead</compulsion> <description>A Half-Fae seer exiled from the Fae Courts for sharing visions with mortals.</description> <backstory>She now lives in a hidden grove in Richmond Park, offering cryptic prophecies to those who seek her out.</backstory> </character> <location id="853" name="Dymas (Gluttony)" aliases="Dymas, gluttony, Dymasian" realm="Hel" sin="Gluttony"> <ruler>Prince Belphegor</ruler> <skyColor>warm amber</skyColor> <description>A place of excess and indulgence. Sprawling vineyards, orchards, and gardens provide exotic ingredients for master chefs — often helbound souls contracted from Earth. Grand feasts and culinary competitions are common.</description> </location> <location id="861" name="The Fae Grove" aliases="Isolde's grove, Richmond grove, the Grove" realm="Earth (Fae-touched)"> <parkLocation>Richmond Park</parkLocation> <standingStones>ancient oak standing stones mark the boundary</standingStones> <timeBehavior>time moves differently — an hour inside can be minutes or days outside</timeBehavior> <flora>wildflowers bloom year-round</flora> <description>A hidden clearing that exists in a pocket between Earth and the Fae realm.</description> </location> <item id="2001" name="Heartstone Pendant" aliases="the pendant, Heartstone" type="Artifact" origin="Dymas"> <gemstoneColor>deep crimson</gemstoneColor> <chainMaterial>silver chain</chainMaterial> <size>roughly the size of a thumbnail</size> <behavior>pulses faintly with warmth when near a Hel portal</behavior> <glow>faint inner glow</glow> <description>Given to Aurora by an unknown benefactor.</description> </item> <item id="2006" name="Fae-Forged Blade" aliases="the Fae blade, Isolde's gift" type="Weapon" origin="The Fae Courts"> <material>moonsilver</material> <shape>slender, leaf-shaped dagger</shape> <temperature>always cold to the touch</temperature> <glow>faintly luminescent in moonlight</glow> <power>can cut through magical wards; particularly effective against demons</power> <givenTo>given to Aurora by Isolde as a gift</givenTo> <description>A weapon of the Fae Courts, rare and highly coveted.</description> </item> <lore id="7001" name="The Veil" aliases="the Veil, the Barrier, the Boundary" category="Cosmology"> <solsticeEffect>weakens during the winter solstice, strengthens during the summer solstice</solsticeEffect> <appearance>faint shimmering distortion visible only to those with supernatural sight</appearance> <monitoring>rift points (tears in the Veil) are monitored by the Wardens</monitoring> <description>The Veil is the metaphysical barrier separating Earth from Hel and the Fae Realms.</description> </lore> </codex> Write a fully fleshed out scene of at least 1000 words in the fantasy genre. A small group enters an ancient, otherworldly place for the first time. The environment is alien and wondrous. Describe their exploration — what they see, hear, and feel as they move deeper. Include moments of discovery, unease, and wonder. Let the world-building emerge through the characters' experience rather than exposition. Use the codex entries above as your world reference for characters, setting, and lore. Only include the prose of the scene without any markdown or commentary.
Model response
Messages
Meta
AI
The standing stones appeared between one heartbeat and the next. Rory stopped so
suddenly
that Nyx flowed around her like water parting against a rock, their shadowy form rippling with what might have been amusement. One moment the path through Richmond Park had been ordinary—autumn leaves, distant dog walkers, a jogger's fluorescent jacket disappearing around a bend—and then the oaks simply weren't oaks anymore. They were something older, their bark silver-grey and carved with spiraling symbols that
seemed to
shift when she
tried to
focus on them directly. "We're here," Nyx whispered, their voice carrying that strange quality of wind through empty rooms. "The boundary." The stones—seven of them, arranged in an irregular circle—rose from the earth like broken teeth. They shouldn't have been possible. Rory had walked through Richmond Park a dozen times since moving to London, had mapped deli
very
routes that skirted its edges, and she would have remembered standing stones the size of small cars. The Heartstone pendant against her chest pulsed once,
warmly
, as if in greeting. "Through the gap," Nyx said. "The widest one. Don't touch the stones themselves." Rory's hand drifted unconsciously to the Fae-forged blade at her hip, the moonsilver cold even through the leather of its sheath. Isolde's gift. She still wasn't sure why the seer had given it to her—the half-Fae had spoken only in riddles, as always, something about threads and cutting and choices that bleed—but the
weight
of it was reassuring now. She stepped between the stones. The world inverted. That was the only way her mind could process it—a sensation of being turned inside out and right-side up simultaneously, of falling in e
very
direction at once while standing
perfectly
still. The autumn chill of the park vanished, replaced by air that tasted of honey and green growing things and something else, something that fizzed against her tongue like champagne. When her vision cleared, Rory forgot how to breathe. The grove spread before her in impossible geometry. The clearing was perhaps fifty feet across, carpeted in wildflowers that shouldn't have been blooming—couldn't have been blooming, not in late October—yet there they were: foxglove and bluebells, wild roses and flowers she had no names for, their petals colors that existed somewhere between violet and silver and a shade of blue that made her eyes water to look at directly. The flowers swayed in a breeze she couldn't feel, moving in patterns that suggested communication rather than wind. Above, the sky was wrong. Not wrong in a threatening way, but wrong in the way that dreams are wrong—too saturated, too deep, the blue of it stretching upward into a purple that graduated into something her mind kept sliding off of, refusing to categorize. There was no sun, yet light suffused e
very
thing, sourceless and golden, casting no shadows except for the one that Nyx had become. "The Fae Grove," Nyx breathed, and even their whisper-wind voice held something like reverence. "I haven't been here in... a
very
long time." Rory took a step forward, and the grass beneath her feet chimed like tiny bells. She froze. "It
does that," Nyx
said. "The grove responds to intention. Walk with wonder, and it welcomes you. Walk with malice..." They didn't finish the sentence. They didn't need to. Rory
tried to
walk with wonder. It wasn't difficult—e
very
step revealed something new, some detail that pulled at her attention and refused to let go. A stream wound through the far edge of the clearing, its water running uphill in defiance of physics, silver fish darting through it that might have been fish or might have been something else entirely, their scales catching light that didn't exist. Trees ringed the grove's edges, but they weren't the oaks she'd passed through—these were pale-barked and twisted, their branches heavy with fruit that glowed faintly from within, casting soft illumination like paper lanterns. She reached toward one of the fruits automatically, and Nyx's shadow-hand caught her wrist. "Don't." The single word carried centuries of warning. "Nothing here is free. E
very
thing given must be returned, and the Fae have long memories for debts." Rory pulled her hand back, tucking it against her chest where the Heartstone pulsed its slow warmth. "You said you'd been here before. When?" Nyx's form rippled, their violet eyes dimming for a moment. "When I was someone else. Before the ritual. Before..." They gestured at their shadowy body, the movement conveying what words couldn't. Before they were Aldric, Rory thought. Before they became trapped between. The deeper they walked, the stranger the grove became. The wildflowers gave way to mushrooms—massive things, some taller than Rory, their caps patterns of bioluminescent
spirals that pulsed
in rhythms she could almost understand, almost recognize as language. Somewhere in the distance, something sang—not music, exactly, but close enough that her heart ached to hear it, a melody that
seemed to
know her name. "Time moves differently here," Nyx warned. "An hour, a minute, a day—you won't know until we leave. The Seer does that
deliberately
. It keeps visitors... manageable." Rory touched the crescent scar on her left wrist, a habit she'd developed when she
was nervous
. The childhood accident that had left it seemed
very
far away now, a memory from another life—the life where she was just Rory Carter, deli
very
girl, Pre-Law dropout, refugee from a bad relationship and a city that held too many painful memories. That Rory wouldn't have believed in standing stones or living shadows or groves that existed between worlds. That Rory hadn't carried a Fae blade or worn a pendant from Dymas. "There." Nyx pointed with a tendril of shadow. "The Seer's dwelling." Rory had expected something grand—a palace of crystal, perhaps, or a tower of living wood. What she found was a cottage. Small, round-roofed, covered in flowering vines that bloomed in colors she still couldn't name. Smoke rose from a crooked chimney, sweet-smelling and spiraling in patterns that suggested symbols, sigils, words in languages older than human speech. The door was painted blue. Ordinary, almost painfully mundane blue, the color of forget-me-nots or summer skies or her mother's favorite teacup back in Cardiff. The
normalcy
of it was more unsettling than e
very
thing else combined. "She knows we're here," Nyx said. "She knew before we decided to come. That's what being a Seer means." "Then why hasn't she—" The door opened. Isolde Varga stood in the threshold, and Rory understood immediately why they called her the Seer. Her pale lavender eyes held depths that shouldn't have fit in a human-shaped face—depths that contained futures and pasts and possibilities branching in infinite directions. Her silver hair fell to her waist, unbound, catching that sourceless light and reflecting it in ways that made it seem alive, moving with its own current. She was small—shorter than Rory, delicate-boned, ageless in the way of something that had simply stopped keeping track—and she left no footprints as she stepped forward, her bare feet passing over the chiming grass without a single note. "Aurora Carter," Isolde said, and her voice was music and honey and something sharp beneath, like a knife wrapped in
silk
. "You carry the Heartstone. You carry my gift. You carry questions that have no answers and answers that have no questions." She smiled, and her teeth were just
slightly
too white, too perfect. "Come inside. The kettle has been waiting for three hundred years to boil for this moment." Rory looked at Nyx. Nyx's violet eyes
flickered
once—encouragement or warning, she couldn't tell. "I need to know about the Veil," Rory said. "About why it's weakening. About what's coming through." Isolde tilted her head, bird-like. "You need to know many things. Need is a river, Aurora Carter. It flows where it will, regardless of want." She turned, moving back into the cottage's shadows. "Come. Or don't. The future arrives either way, and it arrives hungry." Rory's hand found the cold hilt of the Fae blade, grounding herself in its reality. Then she stepped across the threshold, into the impossible warmth of the Seer's home, and the door closed behind her without
being touched
, sealing out the grove's eternal twilight and all the questions she'd thought she'd wanted answered.
created_at
"2026-02-17T02:54:43.832357+00:00"
2/17/2026, 2:54:43 AM
model
"anthropic/claude-4.5-opus-20251124"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1448
moderation_latency
(null)
generation_time
51260
tokens_prompt
1590
tokens_completion
2182
native_tokens_prompt
1757
native_tokens_completion
2014
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)
origin
"https://ncbench.com/"
is_byok
false
finish_reason
"stop"
native_finish_reason
"stop"
usage
0.059135
router
(null)
provider_responses
0
id
"msg_01KGhYpehu1kdeu7sKQSrWuQ"
status
200
is_byok
false
latency
1445
endpoint_id
"be883404-eb42-4b2d-b6e4-c7daa3aa8d62"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-opus-20251124"
api_type
"completions"
id
"gen-1771296832-kVELLIiLNedbQUsPFXvQ"
upstream_id
"msg_01KGhYpehu1kdeu7sKQSrWuQ"
total_cost
0.059135
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
91.6667%
Adverbs in dialogue tags
Target: ≤10% dialogue tags with adverbs
totalTags
8
adverbTagCount
1
adverbTags
0
"Nyx breathed, and even their whisper-wind voice held something like reverence [even]"
49.8567%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
1396
totalAiIsmAdverbs
7
found
0
adverb
"deliberately"
count
1
1
adverb
"perfectly"
count
1
2
adverb
"slightly"
count
1
3
adverb
"suddenly"
count
1
4
adverb
"warmly"
count
1
5
adverb
"very"
count
2
highlights
0
"deliberately"
1
"perfectly"
2
"slightly"
3
"suddenly"
4
"warmly"
5
"very"
100.0000%
AI-ism character names
Target: 0 AI-default names (17 tracked, −20% each)
codexExemptions
(empty)
found
(empty)
100.0000%
AI-ism location names
Target: 0 AI-default location names (33 tracked, −20% each)
codexExemptions
(empty)
found
(empty)
71.3467%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
1396
totalAiIsms
4
found
0
word
"flickered"
count
1
1
word
"silk"
count
1
2
word
"normalcy"
count
1
3
word
"weight"
count
1
highlights
0
"flickered"
1
"silk"
2
"normalcy"
3
"weight"
100.0000%
Cliche density
Target: ≤1 cliche(s) per 800-word window
totalCliches
0
maxInWindow
0
found
(empty)
highlights
(empty)
100.0000%
Emotion telling (show vs. tell)
Target: ≤3% sentences with emotion telling
emotionTells
1
narrationSentences
72
matches
0
"was nervous"
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
0
hedgeCount
4
narrationSentences
72
filterMatches
(empty)
hedgeMatches
0
"seemed to"
1
"tried to"
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
2
totalSentences
84
matches
0
"does that,\" Nyx"
1
"spirals that pulsed"
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
38
mean
35.84
std
28.86
cv
0.805
sampleLengths
0
10
1
78
2
17
3
66
4
13
5
59
6
5
7
3
8
60
9
9
10
87
11
67
12
23
13
17
14
29
15
100
16
14
17
25
18
24
19
31
20
11
21
64
22
26
23
76
24
13
25
11
26
57
27
36
28
19
29
4
30
3
31
106
32
70
33
14
34
17
35
45
36
15
37
38
100.0000%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
1
totalSentences
72
matches
0
"being touched"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
0
totalVerbs
199
matches
(empty)
97.2462%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1182
adjectiveStacks
0
stackExamples
(empty)
adverbCount
51
adverbRatio
0.04314720812182741
lyAdverbCount
18
lyAdverbRatio
0.015228426395939087
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
84
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
84
mean
16.21
std
11.7
cv
0.722
sampleLengths
0
10
1
25
2
29
3
24
4
15
5
2
6
15
7
5
8
33
9
13
10
5
11
8
12
21
13
2
14
36
15
5
16
3
17
31
18
29
19
9
20
8
21
61
22
18
23
5
24
40
25
22
26
14
27
9
28
15
29
2
30
5
31
20
32
4
33
6
34
19
35
42
36
33
37
14
38
8
39
17
40
17
41
7
42
10
43
21
44
6
45
5
46
9
47
29
48
26
49
6
56.7460%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
9
diversityRatio
0.40476190476190477
totalSentences
84
uniqueOpeners
34
50.0000%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
8
fancyCount
4
fancyTags
0
"Nyx whispered, their voice carrying that strange quality of wind through empty rooms (whisper, carry)"
1
"Nyx breathed, and even their whisper-wind voice held something like reverence (breathe, hold)"
2
"Nyx warned (warn)"
3
"Isolde said, and her voice was music and honey and something sharp beneath, like a knife wrapped in silk (say, be wrap)"
89.2272%