NC Bench
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Run: 2026-02-17-01KHMQJKM5YSHPTFMNXG3CMWQH
Run Details
Model:
Claude Opus 4.6
Test:
Bad Writing Habits
Scenario:
Mystery: examining a crime scene
Duration:
1m 24s
Cost:
$0.085115
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="4416" name="Detective Harlow Quinn" aliases="Quinn, Detective Quinn, Harlow" pronouns="she/her" species="Human" storyRole="Antagonist"> <eyeColor>brown</eyeColor> <hair>closely cropped salt-and-pepper</hair> <height>5'9"</height> <age>41</age> <jawline>sharp jaw</jawline> <watch>worn leather watch on her left wrist</watch> <bearing>military precision</bearing> <description>A Metropolitan Police detective with 18 years of decorated service who suspects the clique is involved in criminal activity.</description> <backstory>She lost her partner, DS Morris, during a case three years ago under unexplained circumstances that had supernatural origins she doesn't yet understand.</backstory> </character> <character id="4414" name="Eva Kowalski" aliases="Eva, Evie" pronouns="she/her" species="Human" storyRole="Best Friend"> <eyeColor>green</eyeColor> <hair>curly red</hair> <height>5'4"</height> <age>26</age> <glasses>round glasses</glasses> <satchel>worn leather satchel full of books</satchel> <freckles>freckled complexion</freckles> <nervousHabit>tucking hair behind her left ear</nervousHabit> <description>Aurora's childhood friend and an occult researcher.</description> <backstory>Moved to London two years before Aurora and works as a research assistant at the British Museum's restricted archives. She holds a master's degree in Ancient History from Oxford.</backstory> </character> <location id="856" name="The Veil Market" aliases="Veil Market, the Market, underground market" realm="Earth"> <currentLocation>abandoned Tube station beneath Camden</currentLocation> <entryRequirement>bone token</entryRequirement> <schedule>moves locations every full moon</schedule> <description>A hidden supernatural black market that sells enchanted goods, banned alchemical substances, and information.</description> </location> <item id="2004" name="Veil Compass" aliases="the Compass, shadow compass" type="Tool" origin="The Veil Market"> <casingMaterial>small brass compass</casingMaterial> <faceMarkings>face etched with protective sigils</faceMarkings> <needle>points toward the nearest supernatural rift or portal</needle> <patina>casing has a patina of verdigris</patina> <creator>crafted by a Shade artisan</creator> <description>A compass attuned to supernatural energy.</description> </item> </codex> Write a fully fleshed out scene of at least 1000 words in the mystery genre. A detective arrives at a crime scene in an unusual location. Something is wrong — the evidence doesn't add up. A colleague is present, offering a different interpretation. Through careful observation and deduction, the detective begins to see what others have missed. Use the codex entries above as your world reference for characters and setting. Only include the prose of the scene without any markdown or commentary.
Model response
Messages
Meta
AI
The bone token felt like a dead tooth in Quinn's palm. She turned it over twice, running her thumb across the crude sigil carved into its surface, then held it up to the rusted service door set into the tiled wall of Camden Town station's lowest maintenance corridor. The lock clicked without her touching it. The door swung inward on silent hinges, which was wrong in itself — hinges that old should have screamed. "After you, Detective." The uniformed constable behind her, PC Wardlow, gestured with exaggerated politeness. He was young enough to think this was exciting. Quinn pocketed the token and stepped through. The abandoned platform beyond opened up like the throat of something vast. Victorian brickwork arched overhead, blackened with a century of soot, and the old track bed had
been filled
in with packed earth and wooden pallets. Naked bulbs strung on wire cast pools of amber light that didn't quite connect, leaving trenches of shadow between them. The air smelled of tallow, dried herbs, and something metallic that sat on the back of Quinn's tongue like a coin. This was the Veil Market — or what was left of it. The stalls were still here, makeshift tables of reclaimed wood and draped fabric, but the merchants
were gone
. Every last one. In their place: evidence markers, a forensic photographer's flash popping in the middle distance, and the quiet industry of a crime scene already hours old. Quinn checked her worn leather
watch
. Half four in the morning. She'd been pulled from a dreamless sleep by Dispatch, told only that a body had been found in an unusual location beneath Camden and that her name had been specifically requested. She didn't like having her name requested. It usually meant the requesting party wanted someone to blame when things went sideways. She moved down the platform with the deliberate, measured stride that eighteen years of service had drilled into her bones. Her brown eyes swept the scene in sectors — left to right, floor to ceiling, near to far. The stalls had
been abandoned
in haste. Goods remained on tables: jars of viscous liquid in colors that had no business existing in nature, bundles of dried plants she didn't recognize, stacks of paper covered in symbols that made her eyes itch when she looked at them too long. On one table, a collection of small brass objects caught the light. Compasses, maybe, though the faces
were etched
with markings that weren't cardinal directions. She picked one up with a gloved hand. The casing was green with verdigris, the brass gone soft with age, and the needle inside didn't point north. It swung
lazily
, then locked onto a position somewhere behind her left shoulder. She set it down and made a note. The body was at the far end of the platform, near what would have been the tunnel mouth before it
was bricked
up. A man, mid-fifties, heavy build, lying on his back with his arms at his sides as though he'd
been laid
out with care. He wore a long coat over layers of mismatched clothing. His eyes were open. His expression was peaceful, which was the first thing that didn't add up. The second thing was the complete absence of any visible cause of death. Quinn crouched beside him, her sharp jaw set, and studied his face. No bruising. No petechiae. No foam at the lips or nose. His skin had a grayish pallor, but that could be the lighting. She checked his hands — no defensive wounds, no broken nails, no abrasions. His coat
was buttoned
neatly. One of his boots
was untied
, but that was it for signs of disorder. "Who found him?" she asked without looking up. "Anonymous tip to the 999 line," Wardlow said from behind her. "Caller described the location in detail but rang off before giving a name. Dispatch traced it to a burner mobile. Dead end." "And who requested me specifically?" Wardlow hesitated. "That came through the DCI's office. I don't have details." Quinn filed that away. She leaned closer to the dead man's face and caught a faint scent — not decomposition, not yet, but something sweet and astringent, like burnt sugar cut with rubbing alcohol. She'd smelled it before. Three years ago, in a warehouse in Deptford, kneeling beside DS Morris's body while paramedics told her there was nothing to be done. Morris, who had been forty-two and fit and who had died with the same peaceful expression and the same absence of any goddamn explanation. Her hands didn't shake. She wouldn't let them. She stood and turned to
find that a
new arrival had appeared at the edge of the scene, just inside the perimeter tape that someone had strung between two stall posts. The woman was short, red-haired, bespectacled, and looked like she'd dressed in the dark — mismatched cardigan over a rumpled blouse, a worn leather satchel bulging with books slung across her body. She
was talking
to Wardlow with the rapid,
slightly
breathless cadence of someone who'd been running. Quinn crossed to them in six strides. "This is a closed crime scene." She said it flatly, a statement of fact rather than an accusation, though the accusation was there if you knew where to look. The woman pushed her round glasses up her nose and tucked a curl of red hair behind her left ear. "I know. I'm the one who called it in." Quinn stared at her. "The anonymous tip." "Eva Kowalski. I'm a research assistant at the British Museum. The restricted archives." She said this last part quietly, as though it were a credential that mattered. Maybe here it did. "I was — I come here sometimes. For research. I arrived tonight and found... him." She glanced toward the body with an expression that was more troubled than frightened. "And I called you. Well, I called 999, and then I called your DCI's office and asked for you by name." "Why me?" Kowalski met her gaze. Her green eyes were steady behind the round lenses. "Because three years ago, your partner died in exactly the same way. And I don't think you've stopped looking for answers." The silence that followed was the kind that has
weight
. Quinn felt it settle across her shoulders like a coat. Wardlow looked between them, clearly lost. "Wardlow," Quinn said, "go and check whether forensics have finished with the north end of the platform. Take your time." He went. Quinn waited until his
footsteps
faded before turning back to Kowalski. "Start talking." Kowalski reached into her satchel and pulled out a small leather-bound notebook, its pages bristling with colored tabs. "The Veil Market moves every full moon. New location, new entrance, new bone tokens distributed to the regulars. But this cycle, something's been wrong. The merchants have been nervous. Three of them packed up and left two days ago — a Shade artisan who makes those compasses, an alchemist who deals in banned substances, and an information broker who goes by the name Needle. They all left within hours of each other." "You know these people." "I know of them. I study them. There's a difference." She tucked the curl behind her ear again. "The point
is that they
sensed something coming, and they ran. Everyone who didn't run is gone too — not fled, just gone. Empty stalls, goods left behind, no sign of struggle. And then there's him." Quinn looked back at the body. "No identification on him. Not yet." "His name is Gresham. Malcolm Gresham. He was the market's steward — the person who managed the location, distributed the tokens, settled disputes. He's been running this operation for at least fifteen years." Kowalski's voice dropped. "He was also the last person to see your partner alive." Quinn's jaw tightened. She could feel the muscle jumping beneath the skin. "You're going to need to explain how you know that." "Because DS Morris came to the Veil Market three years ago. He was investigating something — I don't know what, my sources are incomplete — and Gresham was his contact. Morris met with him, left, and was dead within six hours." She opened her notebook to a tabbed page and held it out. "I've been researching cases like this. Unexplained deaths with no visible cause. There have been seven in London in the last four years, all connected to people who had recent contact with supernatural artifacts or locations. Your partner's case was the third." Quinn took the notebook. The page
was covered
in Kowalski's small, precise handwriting — dates, names, locations, connected by lines and arrows in different colored ink. It looked like the work of either a brilliant researcher or a paranoid conspiracist. Quinn had learned, over the years, that the line between the two was thinner than most people were comfortable admitting. "You said the evidence doesn't add up," Quinn said
slowly
. "What's your interpretation?" Kowalski glanced around the empty market, and Quinn
watch
ed her eyes linger on the shadows between the light pools. There was something in those shadows — not movement, exactly, but an absence of stillness, as if the dark itself
were breathing
. "Look at the body's position," Kowalski said. "Arms at his sides. Coat buttoned. He wasn't attacked — he was shut down. Like a machine switched off. And look at the stalls." Quinn looked. She'd already catalogued the abandoned goods, the hasty departure of the merchants, the disorder that suggested fear. But Kowalski
was pointing
at something else — the pattern of the disorder. Quinn followed her finger and felt the back of her neck prickle. The stalls closest to the body were undisturbed. Every object in place, every jar aligned, every surface dust-free. It was the stalls farthest from the body that showed signs of panic — overturned jars, scattered papers, a chair knocked sideways. Whatever had frightened the merchants, it hadn't come from Gresham's direction. It had come from the other end of the platform. The merchants had fled toward Gresham, and then past him, and then out. But Gresham hadn't fled at all. "He stayed," Quinn said. "He stayed," Kowalski confirmed. "He knew what was coming. He faced it." Quinn walked back to the table with the brass compasses. She picked up the one she'd examined before and held it flat on her palm. The needle swung,
quivered
, and locked again — pointing toward the bricked-up tunnel mouth behind the body. The same direction the merchants had fled from. "These compasses," she said. "What do they point to?" "Supernatural rifts. Portals. Tears in the boundary between here and somewhere else." Kowalski's voice was quiet, almost gentle, as though she
were trying
to deliver bad news without breaking something. "They're called Veil Compasses. A Shade artisan makes them — the same one who packed up and left two days ago." Quinn
watch
ed the needle. It didn't waver. It pointed at the bricked-up tunnel mouth with the
unwavering
conviction of a hunting dog on a scent. "Something came through," she said. It wasn't a question. "Something came through," Kowalski agreed. "And I think it's the same thing that killed your partner. The same thing that's killed at least seven people in four years. And Gresham knew it was coming, and he stayed, and he died, and I think he did it on purpose." Quinn set the compass down
carefully
. She turned to face Kowalski and studied her — the freckled face, the nervous hands, the satchel full of books and research and years of quiet obsession with things that most people would call impossible. "Why come to me?" Quinn asked. "Why not take this to someone who already believes in — " She gestured at the market, the compasses, the impossible underground cathedral of the weird. "All of this." Kowalski's expression shifted. Something old and sad moved behind her green eyes. "Because the people who already believe are either dead, or they ran. I need someone who can investigate. Someone with authority and resources and the kind of stubborn that doesn't let go of a case for three years." She paused. "And because you deserve to know what killed your partner. Even if the answer doesn't look like anything you've been trained to accept." Quinn looked at the body of Malcolm Gresham, laid out like a man who'd gone to sleep and simply never woken up. She looked at the Veil Compass, its needle pointing toward a wall of Victorian brick that should have been the end of the line but somehow wasn't. She thought about Morris — his laugh, his terrible coffee, the look on his face the last time she'd seen him alive, as though he'd glimpsed something that language hadn't
been built
to describe. She pulled out her phone and dialed the forensics lead. "This is DI Quinn. I want a full workup on the deceased — toxicology, histology, everything. And I want the tunnel mouth behind him examined. The brickwork. Check for any structural anomalies, gaps, anything that doesn't match the original construction." She paused. "And bag every one of those brass compasses on the third stall from the left. I'm taking them into evidence." She hung up and looked at Kowalski. "You're going to show me everything in that notebook. And then you're going to take me through every case, every connection, every piece of research you've done. All of it." Kowalski nodded. She tucked the curl behind her ear one more time. "There's a coffee shop on Parkway that opens at five," she said. Quinn checked her
watch
. Ten to five. Close enough. She took one last look at the Veil Market — the abandoned stalls, the dead man, the compass needles all pointing toward something she couldn't yet see — and followed Eva Kowalski toward the door, stepping
carefully
over the threshold and back into a world that
suddenly
felt thinner than it had four hours ago.
created_at
"2026-02-17T02:42:48.510836+00:00"
2/17/2026, 2:42:48 AM
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1329
moderation_latency
(null)
generation_time
84065
tokens_prompt
923
tokens_completion
3511
native_tokens_prompt
938
native_tokens_completion
3217
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
0.085115
router
(null)
provider_responses
0
id
"msg_01N3LbpJysLt4qK2rx9xwoFd"
status
200
is_byok
false
latency
1329
endpoint_id
"c926c048-563e-44b0-8434-95965bee924c"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.6-opus-20260205"
api_type
"completions"
id
"gen-1771296083-xGENFZFdC125lJtJ1Jp2"
upstream_id
"msg_01N3LbpJysLt4qK2rx9xwoFd"
total_cost
0.085115
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
100.0000%
Adverbs in dialogue tags
Target: ≤10% dialogue tags with adverbs
totalTags
14
adverbTagCount
1
adverbTags
0
"Quinn said slowly [slowly]"
74.0147%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
2309
totalAiIsmAdverbs
6
found
0
adverb
"carefully"
count
2
1
adverb
"lazily"
count
1
2
adverb
"slightly"
count
1
3
adverb
"slowly"
count
1
4
adverb
"suddenly"
count
1
highlights
0
"carefully"
1
"lazily"
2
"slightly"
3
"slowly"
4
"suddenly"
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)
78.3456%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
2309
totalAiIsms
5
found
0
word
"quivered"
count
1
1
word
"unwavering"
count
1
2
word
"weight"
count
1
3
word
"footsteps"
count
1
4
word
"etched"
count
1
highlights
0
"quivered"
1
"unwavering"
2
"weight"
3
"footsteps"
4
"etched"
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
0
narrationSentences
132
matches
(empty)
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
2
hedgeCount
0
narrationSentences
132
filterMatches
0
"watch"
hedgeMatches
(empty)
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
2
totalSentences
158
matches
0
"find that a"
1
"is that they"
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
62
mean
37.55
std
29.01
cv
0.773
sampleLengths
0
74
1
23
2
7
3
78
4
58
5
63
6
112
7
48
8
73
9
13
10
67
11
8
12
33
13
5
14
12
15
85
16
8
17
79
18
7
19
29
20
29
21
7
22
81
23
2
24
34
25
26
26
20
27
13
28
2
29
90
30
4
31
54
32
12
33
47
34
22
35
95
36
60
37
13
38
41
39
31
40
44
41
80
42
4
43
12
44
50
45
9
46
51
47
25
48
9
49
48
77.7778%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
11
totalSentences
132
matches
0
"been filled"
1
"were gone"
2
"been pulled been found"
3
"been abandoned"
4
"were etched"
5
"was bricked"
6
"been laid"
7
"was buttoned"
8
"was untied"
9
"was covered"
10
"been built"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
4
totalVerbs
275
matches
0
"was talking"
1
"were breathing"
2
"was pointing"
3
"were trying"
94.0000%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1576
adjectiveStacks
1
stackExamples
0
"small leather-bound notebook,"
adverbCount
47
adverbRatio
0.02982233502538071
lyAdverbCount
15
lyAdverbRatio
0.00951776649746193
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
158
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
158
mean
14.73
std
12
cv
0.814
sampleLengths
0
11
1
37
2
7
3
19
4
14
5
9
6
7
7
12
8
25
9
20
10
21
11
12
12
18
13
3
14
25
15
6
16
5
17
31
18
7
19
14
20
20
21
18
22
7
23
42
24
12
25
13
26
8
27
19
28
13
29
8
30
23
31
23
32
10
33
4
34
13
35
13
36
12
37
2
38
2
39
7
40
12
41
13
42
5
43
14
44
8
45
11
46
22
47
5
48
2
49
10
42.1941%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
15
diversityRatio
0.310126582278481
totalSentences
158
uniqueOpeners
49
100.0000%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
14
fancyCount
3
fancyTags
0
"Quinn said slowly (say slowly)"
1
"Kowalski confirmed (confirm)"
2
"Kowalski agreed (agree)"
92.1372%