NC Bench
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About
Tests
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Vendors
Run: 2026-02-17-01KHMR1E13JZGJ1JJFPH5Y6SRD
Run Details
Model:
Claude Opus 4.6
Test:
Bad Writing Habits
Scenario:
Mystery: examining a crime scene
Duration:
1m 21s
Cost:
$0.079890
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 wrong in Quinn's palm. Too light for something carved from actual bone, too warm against her skin for the chill of the tunnel they'd descended through. She pocketed it and ducked beneath the police tape that Constable Reid had strung, with admirable optimism, across the entrance to a place that shouldn't exist. The abandoned Tube station opened before her like the ribcage of some vast, dead animal. Tiled walls arched overhead, their ceramic faces cracked and weeping with condensation, and the old platform str
etched
into shadow beyond the reach of the portable halogen lamps the forensic team had erected. But it wasn't the station itself that stopped Quinn two steps past the tape. It was what had
been built
inside it. Stalls. Dozens of them. Timber frames draped in fabrics she couldn't name, their surfaces catching the halogen light in ways that made her eyes ache. Tables still laden with merchandise — glass vials stoppered with wax, bundles of dried herbs that smelled of nothing she recognized, books bound in leather that was too supple, too dark. The place looked like a market that had
been evacuated
in a hurry, vendors abandoning their wares mid-transaction. Coins of unfamiliar currency littered the flagstone floor. A cage near the entrance held something that might have been a bird, except it had too many wings and all of them were still. Quinn pulled on a pair of nitrile gloves with the mechanical efficiency of someone who'd done it ten thousand times and moved toward the center of the platform, where the forensic tent glowed like a paper lantern. The body was male, early thirties, sprawled on his back between two overturned market stalls. He wore a long coat of dark wool, well-tailored, and his hands were bare. No defensive wounds. No visible cause of death. His expression was calm, almost serene, as if he'd simply decided to lie down and stop. That was the first thing that bothered her. The second thing was the circle. Someone had drawn — no, scorched — a ring into the flagstone around the body, roughly eight feet in diameter. The stone inside the circle was a shade darker than the stone outside it, as though it had
been exposed
to tremendous heat. But the body showed no burns. The wool coat wasn't singed. Even the man's eyebrows were intact. Quinn crouched at the circle's edge and ran a gloved finger along the scorched line. The residue was fine, almost powdery, and it clung to the nitrile with a faint iridescence that disappeared when she tilted her hand. "Time of death?" she asked without looking up. Dr. Adebayo, the pathologist, straightened from his crouch on the other side of the body. "That's part of the problem. Core temperature suggests he's been dead roughly six hours, but rigor's barely begun. And lividity is..." He paused, choosing his words with the care of a man who didn't want to sound unhinged. "Lividity is inconsistent with position. Blood's pooled as though he was standing upright when he died and
stayed that way
for some time before falling." Quinn looked at the body again. Flat on his back, arms at his sides. "Standing upright. For how long?" "Hours, potentially. But if that's the case, rigor should be far more advanced. The biochemistry doesn't track." She stood, knees popping, and pulled out her phone to photograph the scene. The first picture came out overexposed, washed in light, though the halogens hadn't
flickered
. The second was fine. She took six more and moved on. A young woman
was waiting
for her at the edge of the forensic tent, clutching a worn leather satchel against her hip as though it were a flotation device. Red curls spilled over the collar of her jacket, and round glasses caught the halogen glare. Eva Kowalski tucked a strand of hair behind her left ear and took a visible breath before speaking. "They called me because of where the body was found," Eva said. "Not because of the body itself. The Market — this place — it moves. Every full moon. If there was a body here, it was left after the vendors cleared out, or—" "Or during the clearing," Quinn said. She
watch
ed Eva's face
carefully
. The younger woman's freckles stood out
sharply
against skin that had gone pale. "You've been here before." It wasn't a question. Eva's gaze skittered to the stalls, the abandoned merchandise, the dead bird-thing in its cage, and Quinn saw recognition in every micro-expression. The slight widening of the eyes at the fabric-draped stalls. The way her nostrils flared near the herb bundles, as though she knew what they should smell like. The way she didn't ask what any of it was. "The British Museum has records of places like this," Eva said, which was not a denial. "Underground markets dealing in... esoteric goods. There's historical precedent going back centuries. The Bartholomew Fair had a shadow counterpart as early as—" "Ms. Kowalski." Quinn's voice was not unkind, but it had edges. "I'm not writing a dissertation. There's a dead man in a circle of scorched stone in a market that sells things I can't identify, and you were brought here because someone in my department thinks you can help me understand what I'm looking at. So help me understand what I'm looking at." Eva closed her mouth. Opened it again. Tucked the curl behind her ear a second time. "The circle is a containment ward," she said quietly. "Or it was. The scorching happens when the ward fails — or when whatever's inside it is too powerful to be held. It's like a circuit burning out." She pointed to the edge nearest Quinn's feet. "There should be sigils along the outer rim. Can you see — yes, there. Those marks." Quinn crouched again. She'd taken them for cracks in the stone, random fracture patterns from the heat. But now that Eva had said the word, she could see it — a repeating pattern, geometric and deliberate,
etched
into the flagstone at precise intervals around the circle's circumference. She'd seen markings like them once before. Only once. Three years ago. The warehouse in Rotherhithe. Morris face-down on the concrete, and the same fine, iridescent residue on Quinn's hands when she'd turned him over. She controlled her breathing. She was good at that. "What was contained?" Quinn asked. "The victim, or something else?" "I don't think this was a containment," Eva said, moving closer. She crouched opposite Quinn, the body between them, and pushed her glasses up her nose with one finger. "The sigils are inverted. See how the angular elements point inward? In a containment ward, they point out — they push against whatever's inside. These are pulling. Drawing something in." She hesitated, green eyes moving to the dead man's serene face. "This was a summoning circle. And based on the lividity Dr. Adebayo described, I think the victim was standing at the center of it when whatever was summoned arrived." Quinn studied the body again. Serene expression. No defensive wounds. He hadn't
tried to
run. He'd stood there and let it happen — or he'd been the one doing the summoning. "So he called something up, and it killed him." "Possibly. Or he was placed in the circle by someone else. A summoning like this would require a — a focal point. Something living, to anchor the energy." Eva's voice had dropped, and she was speaking faster now, the way people did when they were saying things they weren't sure they should say. "Detective, the vendors who operate here, they deal in information as much as goods. If someone was using the Market as a location for this kind of ritual, the vendors would have known. They would have left in a hurry, and they would have left—" "Their stock behind," Quinn finished. She straightened and turned a slow circle, surveying the abandoned stalls with new eyes. Not a crime scene that
happened to
be in a market. A market that had
been abandoned
because its occupants knew what
was coming
. She walked to the nearest stall and began examining its contents with
methodical
precision. Glass vials in wooden racks — some empty, some filled with liquids that moved too
slowly
to be water. A leather roll of tools she didn't recognize, blades curved in ways that served no surgical purpose she could name. And tucked beneath a fold of that strange, light-catching fabric, a small brass compass. Quinn picked it up. The casing was cold and
slightly
green with verdigris, and its face
was covered
in markings — sigils, she recognized them now, the same geometric script as the circle on the floor, though these were smaller, more
intricate
. She turned it over. The needle didn't point north. It swung in a slow, deliberate arc and settled, trembling, toward a point somewhere behind her and to the left. Toward the far end of the platform, where the tunnel mouth gaped black beyond the reach of the lamps. "Don't
touch that." Eva
was on her feet, one hand extended. "Detective — please. That's a Veil Compass. It's attuned to supernatural rifts. If the needle is pointing—" "Then there's a rift," Quinn said. She kept her voice level. The needle hadn't
wavered
. It pointed into the dark with the conviction of a hunting dog on a scent. "At the end of this platform." "Which means whatever was summoned may not have left. It may still be here, or the passage it came through may still be open." Quinn looked at the compass. At the body. At the scorched circle with its inverted sigils. She thought about Morris, about the official report that said cardiac event and the unofficial silence that had swallowed every question she'd asked about the residue on the warehouse floor, the symbols she'd photographed and
been told
to delete, the way Internal Affairs had looked at her when she'd pushed — not with suspicion, but with something closer to pity. She'd spent three years being the detective who couldn't let go. The one who saw patterns that weren't there, who asked questions that made her superiors uncomfortable, who'd been quietly shuffled from Homicide to a liaison role with a department she'd never heard of that dealt with cases no one wanted to talk about. And now here she was, holding a compass that pointed toward something impossible, standing over a body that defied pathology, in a market that sold things from nightmares, and for the first time in three years, the evidence was adding up instead of falling apart. She slipped the compass into an evidence bag. Her hands were steady. "Ms. Kowalski, I'm going to need you to tell me everything you know about this market. Names, schedules, how it operates, who runs it. Everything." "I—" Eva tucked the curl behind her ear. Third time. "There are things I can't—" "Three years ago, my partner died in a warehouse in Rotherhithe." Quinn held up her left hand, the worn leather
watch
catching the light. She'd been wearing it that night too. Same
watch
, same wrist, different world. "The floor
was covered
in marks just like these. The pathologist couldn't explain the cause of death. The case was closed in forty-eight hours, and I was told to move on." She lowered her hand. "I don't move on. So you can either help me now, in a way that's on the record and above board, or I can start pulling on threads. Museum records, your access logs to the restricted archives, the bone token you used to get into this place before we secured it. Your choice." The silence str
etched
between them. Water dripped somewhere in the tunnel, marking time. The dead man lay in his circle and said nothing. Eva Kowalski reached into her satchel and pulled out a small, cloth-wrapped bundle. She set it on the nearest market stall and unfolded the cloth to reveal a notebook — leather-bound, dense with handwriting, pages marked with colored tabs. "The Market moves every full moon," she said. "It was supposed to move three days ago. Something held it here. Whatever was summoned in that circle, it anchored this location. It pinned it in place." She opened the notebook to a tabbed page. "I've been tracking the movements for eighteen months. The pattern broke this cycle. That's why I was already on my way here when your people called." Quinn looked at the notebook. At the meticulous handwriting, the dates, the locations, the small hand-drawn maps. This was not the work of an amateur. This was research. This was obsession. She recognized it the way one addict recognizes another. "Alright," Quinn said. She pulled out her own notebook — standard Metropolitan Police issue, far less impressive — and clicked her pen. "Start from the beginning." Behind her, deep in the tunnel where the compass needle pointed, something shifted in the dark. Neither woman heard it over the hum of the halogen lamps. But the dead bird in the cage near the entrance — the one with too many wings — opened an eye that shouldn't have been able to open, and
watch
ed.
created_at
"2026-02-17T02:50:50.646429+00:00"
2/17/2026, 2:50:50 AM
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1557
moderation_latency
(null)
generation_time
80822
tokens_prompt
923
tokens_completion
3292
native_tokens_prompt
938
native_tokens_completion
3008
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
0.07989
router
(null)
provider_responses
0
id
"msg_01AM1kd94dL1MzkaGwABmQud"
status
200
is_byok
false
latency
1557
endpoint_id
"c926c048-563e-44b0-8434-95965bee924c"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.6-opus-20260205"
api_type
"completions"
id
"gen-1771296569-CvkthVAfEOjvyO6Tyjv3"
upstream_id
"msg_01AM1kd94dL1MzkaGwABmQud"
total_cost
0.07989
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
11
adverbTagCount
1
adverbTags
0
"she said quietly [quietly]"
81.7601%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
2193
totalAiIsmAdverbs
4
found
0
adverb
"carefully"
count
1
1
adverb
"sharply"
count
1
2
adverb
"slightly"
count
1
3
adverb
"slowly"
count
1
highlights
0
"carefully"
1
"sharply"
2
"slightly"
3
"slowly"
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)
77.2002%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
2193
totalAiIsms
5
found
0
word
"flickered"
count
1
1
word
"wavered"
count
1
2
word
"methodical"
count
1
3
word
"intricate"
count
1
4
word
"etched"
count
1
highlights
0
"flickered"
1
"wavered"
2
"methodical"
3
"intricate"
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
130
matches
(empty)
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
1
hedgeCount
2
narrationSentences
130
filterMatches
0
"watch"
hedgeMatches
0
"tried to"
1
"happened to"
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
2
totalSentences
150
matches
0
"stayed that way"
1
"touch that.\" Eva"
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
48
mean
45.9
std
28.94
cv
0.63
sampleLengths
0
56
1
69
2
107
3
37
4
61
5
6
6
60
7
38
8
8
9
78
10
19
11
17
12
38
13
63
14
44
15
28
16
64
17
38
18
63
19
16
20
61
21
56
22
26
23
9
24
10
25
99
26
31
27
9
28
98
29
43
30
67
31
71
32
19
33
28
34
36
35
24
36
76
37
99
38
12
39
25
40
15
41
125
42
23
43
39
44
69
45
40
46
26
47
57
100.0000%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
6
totalSentences
130
matches
0
"been built"
1
"been evacuated"
2
"been exposed"
3
"been abandoned"
4
"was covered"
5
"been told"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
6
totalVerbs
254
matches
0
"was waiting"
1
"was speaking were saying"
2
"was coming"
3
"was, holding was adding"
94.0000%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1540
adjectiveStacks
1
stackExamples
0
"small hand-drawn maps."
adverbCount
36
adverbRatio
0.023376623376623377
lyAdverbCount
10
lyAdverbRatio
0.006493506493506494
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
150
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
150
mean
14.69
std
12.21
cv
0.831
sampleLengths
0
8
1
22
2
26
3
15
4
32
5
14
6
8
7
1
8
3
9
21
10
31
11
18
12
8
13
25
14
37
15
15
16
14
17
3
18
5
19
16
20
8
21
6
22
20
23
23
24
6
25
5
26
6
27
15
28
23
29
8
30
1
31
14
32
38
33
25
34
6
35
8
36
5
37
17
38
13
39
14
40
4
41
7
42
29
43
16
44
18
45
12
46
32
47
6
48
5
49
13
62.6667%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
11
diversityRatio
0.42
totalSentences
150
uniqueOpeners
63
84.0909%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
11
fancyCount
4
fancyTags
0
"Eva said, which was not a denial (say, does be not)"
1
"she said quietly (say quietly)"
2
"Eva said, moving closer (say, move)"
3
"Quinn finished (finish)"
94.1011%