NC Bench
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Run: 2026-02-17-01KHMQV2VVVR67B0PRWEJNKRT5
Run Details
Model:
Claude Opus 4.5
Test:
Bad Writing Habits
Scenario:
Thriller: chase through city streets
Duration:
50.9s
Cost:
$0.058385
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="4417" name="Tomás Herrera" aliases="Tommy, Tomás, Herrera" pronouns="he/him" species="Human" storyRole="Support"> <eyeColor>warm brown</eyeColor> <hair>short curly dark brown</hair> <height>5'10"</height> <age>29</age> <skinTone>olive skin</skinTone> <scar>scar running along his left forearm from a knife attack</scar> <medallion>Saint Christopher medallion around his neck</medallion> <birthplace>Seville, Spain</birthplace> <description>A former paramedic who provides off-the-books medical care for the clique.</description> <backstory>Born in Seville, Spain. He moved to London to work for the NHS but lost his license after administering unauthorized treatments to supernatural patients.</backstory> </character> <location id="854" name="The Raven's Nest" aliases="the Nest, Raven, Silas' bar" realm="Earth"> <signColor>distinctive green neon sign above the entrance</signColor> <secretRoom>hidden back room accessible through a bookshelf, used for clandestine meetings</secretRoom> <description>A dimly lit bar in Soho, London. The walls are covered with old maps and black-and-white photographs.</description> </location> <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> </codex> Write a fully fleshed out scene of at least 1000 words in the thriller genre. A detective is pursuing a suspect through rain-soaked city streets at night. The chase takes them from the street level down into an underground market. The detective must decide whether to follow the suspect into unfamiliar and potentially dangerous territory. 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 rain came down in sheets, turning the Soho streets into rivers of reflected neon. Detective Harlow Quinn's boots slapped against the wet pavement as she rounded the corner onto Greek Street, her breath coming in controlled bursts despite the burning in her lungs. Eighteen years on the force had taught her how to pace herself during a pursuit, how to conserve energy for the moments that mattered. But Tomás Herrera was younger, faster, and he knew these streets in ways she was only beginning to understand. She caught a glimpse of him fifty meters ahead—dark curly hair plastered to his skull, olive skin
gleaming
under the streetlights as he vaulted over a row of rubbish bins. He moved like someone who'd spent years
navigating
the narrow arteries of old European cities, all fluid grace and economy of motion. Quinn had studied his file extensively. Born in Seville. Former NHS paramedic. License revoked under circumstances that still didn't make sense to her, no matter how many times she read the disciplinary report. "Metropolitan Police! Stop!" Her shout
was swallowed
by the rain and the distant thump of bass from the clubs that lined the street. A group of drunk tourists scattered as Herrera barreled through them, and Quinn had to dodge around a woman in heels who'd stumbled into her path. She keyed her radio without breaking stride. "Suspect heading north on Greek Street toward Soho Square. Requesting backup." Static crackled back at her. The radio had been acting up all night, ever since she'd started tailing Herrera from that bar—the Raven's Nest, the sign had said, distinctive green neon cutting through the darkness like a
beacon
. She'd been
watch
ing the place for weeks, cataloguing the strange clientele who came and went through its doors at all hours. The old maps on the walls, the black-and-white photographs that
seemed to
shift when you
weren't looking
directly at them. The hidden back room she'd glimpsed once through a gap in the bookshelf before someone had noticed her looking and the gap had simply... closed. Herrera cut left, and Quinn followed, her worn leather
watch
catching the light as she pumped her arms. The
watch
had been Morris's. Her partner. Three years dead, and she still wore it every day like a talisman against the questions that haunted her. The side street narrowed, the buildings pressing close on either side. Victorian architecture gave way to something older, the brickwork stained with centuries of London grime. Quinn's sharp jaw was set with determination as she closed the distance, her military-precise movements carrying her over obstacles that would have tripped a less disciplined runner. She
was gaining
on him. Twenty meters. Fifteen. Then Herrera did something impossible. He dropped. One moment he
was running
full tilt toward a dead end—a solid wall of brick that had been there since before the Great Fire—and the next he
was gone
, swallowed by the earth as if the pavement had simply opened up beneath him. Quinn skidded to a halt, her boots hydroplaning on the wet stone. Rain dripped from her closely cropped salt-and-pepper hair, running down her face as she stared at the spot where Herrera had vanished. A grate. There was a grate there, she realized, half-hidden by shadows and a pile of sodden cardboard. The kind of thing you'd walk past a thousand times without noticing. She crouched down, her brown eyes scanning the darkness below. A ladder. Rusted, but sturdy enough. And something else—a faint glow, warm and amber, rising from depths that shouldn't exist this close to the surface. The smart play was to wait for backup. Call it in, secure the perimeter, let the tactical team handle whatever was down there. That was procedure. That was protocol. But procedure hadn't explained what
happened to
Morris. Quinn had been twenty yards away when her partner had walked into that warehouse in Deptford, following up on a routine tip about stolen goods. She'd heard the screaming—sounds that couldn't have come from a human throat, sounds that still woke her at three in the morning with her sheets soaked in sweat. By the time she'd breached the door, Morris was dead, his body twisted in ways that defied anatomy, and there was nothing in the warehouse except shadows and the lingering smell of copper and ozone. The official report had said "cardiac event." The unofficial whispers at the station had been worse—accusations of incompetence, of cowardice, of freezing when her partner needed her. But Quinn knew the truth was something else entirely. Something that lived in the gaps between official reports and whispered rumors. Something that moved through the city like blood through veins, invisible to anyone who
wasn't looking
. She'd been looking ever since. The ladder groaned under her
weight
as she descended. The rungs were slick with moisture that didn't feel quite like rain—thicker, somehow, with a faint luminescence that clung to her palms. The amber glow intensified as she dropped below street level, and the sounds of the city above faded until all she could hear was her own heartbeat and a distant murmur, like the hum of conversation in a crowded room. The tunnel opened up into something that shouldn't have been there. Quinn had studied the London Underground extensively after Morris's death, poring over maps both official and otherwise. She knew about the abandoned stations, the ghost platforms, the miles of forgotten Victorian infrastructure that wound beneath the modern city like veins beneath skin. But this was different. This was a station, yes—she could see the remnants of platform signage, the curved walls distinctive to the old Tube architecture—but it had
been transformed
into something else entirely. The Veil Market. She'd heard the name whispered in the interrogation rooms, always by suspects who
seemed to
regret mentioning it the moment the words left their lips. A hidden supernatural black market, they said. Enchanted goods. Banned substances. Information that couldn't be obtained anywhere else. She'd dismissed it as urban legend, the kind of story criminals told each other to seem more connected than they were. Now she
was standing
at its threshold, and dismissal was no longer an option. The abandoned platform had
been converted
into a bazaar that stretched in both directions beyond what the architecture should have allowed. Stalls lined the walls, draped in fabrics that shifted color when she looked directly at them. Lanterns hung from the ceiling—the source of the amber glow—containing flames that burned without heat or smoke. The air smelled of incense and old books and something else, something metallic and alive. And the people. They weren't all people, Quinn realized with a cold shock that settled into her stomach like a stone. Some of them were close enough to human that you'd pass them on the street without a second glance. Others were... not. A woman with skin the color of storm clouds browsed a stall selling glass vials filled with liquid light. A man—if it was a man—stood seven feet tall, his proportions all wrong, his joints bending in directions that made Quinn's eyes water when she
tried to
follow them. A child darted between the stalls, laughing, and when she turned to
watch
him pass, she caught a glimpse of too many teeth in a mouth that stretched too wide. Herrera was nowhere to be seen. Quinn pressed herself against the tunnel wall, her hand moving instinctively to her service weapon. The
weight
of it was reassuring against her hip, though she suspected it would be about as effective down here as throwing rocks at the ocean. She was out of her depth. She knew that. Every instinct she'd honed over eighteen years of police work
was screaming
at her to climb back
up that ladder
and pretend this night had never happened. But there, at the far end of the platform, she could see Herrera. He'd stopped running. He
was talking
to someone—a woman in a dark coat, her face obscured by the shadow of a wide-brimmed hat. Quinn couldn't hear what they
were saying
, but she could see the tension in Herrera's shoulders, the way his hand kept moving to the Saint Christopher medallion at his throat. The woman handed him something small, something that glinted in the lantern light, and Herrera pocketed it
quickly
before glancing back toward the entrance. His eyes met Quinn's. For a moment, neither of them moved. The market continued its strange commerce around them, indifferent to the standoff playing out beneath its amber glow. Quinn could see the scar on Herrera's forearm, the one the file said came from a knife attack during his paramedic days. She'd assumed it was from a patient, maybe a drug-related incident. Now she wondered if the truth was something else entirely. Herrera's expression shifted. Not fear, exactly. Something more complicated. He raised one hand
slowly
, palm out, in a gesture that might have been surrender or might have been warning. The woman in the hat had vanished. Quinn hadn't seen her go. She had a choice to make. Follow Herrera deeper into this market, deeper into a world that operated by rules she didn't understand, chasing answers that might destroy everything she thought she knew about her city and her career and the night her partner died. Or turn around. Climb back
up that ladder
. File a report that no one would believe and go back to working cases that made sense. Quinn thought of Morris. Of the way his body had
been twisted
. Of the screaming. She stepped forward into the amber light. The market swallowed her whole.
created_at
"2026-02-17T02:46:53.08233+00:00"
2/17/2026, 2:46:53 AM
model
"anthropic/claude-4.5-opus-20251124"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
2631
moderation_latency
(null)
generation_time
50795
tokens_prompt
914
tokens_completion
2471
native_tokens_prompt
917
native_tokens_completion
2152
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
0.058385
router
(null)
provider_responses
0
id
"msg_01FQMoK2tJrhFvjUsJqbJx1B"
status
200
is_byok
false
latency
2631
endpoint_id
"be883404-eb42-4b2d-b6e4-c7daa3aa8d62"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-opus-20251124"
api_type
"completions"
id
"gen-1771296361-7kOJamz1BxxmmVbFfF3Z"
upstream_id
"msg_01FQMoK2tJrhFvjUsJqbJx1B"
total_cost
0.058385
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
0
adverbTagCount
0
adverbTags
(empty)
87.6923%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
1625
totalAiIsmAdverbs
2
found
0
adverb
"quickly"
count
1
1
adverb
"slowly"
count
1
highlights
0
"quickly"
1
"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)
69.2308%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
1625
totalAiIsms
5
found
0
word
"beacon"
count
1
1
word
"gleaming"
count
1
2
word
"weight"
count
2
3
word
"navigating"
count
1
highlights
0
"beacon"
1
"gleaming"
2
"weight"
3
"navigating"
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
115
matches
(empty)
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
1
hedgeCount
4
narrationSentences
115
filterMatches
0
"watch"
hedgeMatches
0
"seemed to"
1
"happened to"
2
"tried to"
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
2
totalSentences
117
matches
0
"up that ladder"
1
"up that ladder"
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
40
mean
40.05
std
33.67
cv
0.841
sampleLengths
0
87
1
85
2
3
3
46
4
18
5
104
6
44
7
53
8
8
9
5
10
2
11
43
12
64
13
35
14
29
15
8
16
88
17
64
18
5
19
71
20
11
21
75
22
3
23
64
24
14
25
69
26
3
27
118
28
6
29
77
30
13
31
77
32
4
33
68
34
29
35
12
36
70
37
15
38
7
39
5
100.0000%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
5
totalSentences
115
matches
0
"was swallowed"
1
"was gone"
2
"been transformed"
3
"been converted"
4
"been twisted"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
8
totalVerbs
264
matches
0
"weren't looking"
1
"was gaining"
2
"was running"
3
"wasn't looking"
4
"was standing"
5
"was screaming"
6
"was talking"
7
"were saying"
100.0000%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1609
adjectiveStacks
0
stackExamples
(empty)
adverbCount
47
adverbRatio
0.029210689869484153
lyAdverbCount
16
lyAdverbRatio
0.009944064636420136
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
117
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
117
mean
13.69
std
10.14
cv
0.741
sampleLengths
0
15
1
29
2
24
3
19
4
30
5
22
6
6
7
3
8
3
9
21
10
3
11
20
12
26
13
7
14
11
15
5
16
33
17
21
18
20
19
24
20
1
21
18
22
5
23
2
24
19
25
11
26
15
27
27
28
5
29
2
30
1
31
5
32
2
33
43
34
12
35
22
36
2
37
16
38
12
39
10
40
2
41
4
42
19
43
8
44
15
45
3
46
3
47
8
48
25
49
28
61.8234%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
11
diversityRatio
0.42735042735042733
totalSentences
117
uniqueOpeners
50
100.0000%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
0
fancyCount
0
fancyTags
(empty)
95.2204%