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Run: 2026-02-17-01KHMQWKSM0AQF7J6N6FPNZ1ZF
Run Details
Model:
Claude Opus 4.5
Test:
Bad Writing Habits
Scenario:
Thriller: chase through city streets
Duration:
1m 3s
Cost:
$0.066860
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 Soho's narrow streets into rivers of reflected neon. Detective Harlow Quinn's boots hammered against the wet pavement, each impact sending up sprays of water that soaked through her trousers. Ahead of her, maybe forty meters now, Tomás Herrera ducked around a corner onto Wardour Street. She keyed her radio without breaking stride. "Suspect heading north on Wardour. I'm in pursuit." Static crackled back. The rain
was playing
hell with communications tonight. Quinn wiped water from her eyes and pushed harder. Eighteen years on the force had taught her that the first thirty seconds of a foot chase determined everything. Let a suspect open up distance and you'd lose them in London's labyrinth of alleys and side streets. She wasn't about to let Herrera slip away—not after six months of building a case against the network he served. The green neon glow of The Raven's Nest blurred past on her left. She'd spent three weeks
surveilling that bar
,
watch
ing the parade of faces that came and went through its doors at odd hours. Something was rotten in that place, connections that led to disappearances and deaths she couldn't explain through normal channels. Herrera was her best lead, a former paramedic whose medical license had
been stripped
for reasons the NHS refused to discuss in detail. He cut left, disappearing between two buildings. Quinn followed, her hand brushing the grip of her service weapon but not drawing. Narrow passage. Old Victorian brick slick with rain and decades of grime. Her breath came hard and fast, condensing in the cold night air. The alley opened onto a small courtyard she'd never seen before, despite knowing this neighborhood block by block. That should have been her first warning. A rusted fire escape clung to the back of a building that looked abandoned, its windows dark and empty. Herrera was already climbing. Quinn grabbed the ladder and hauled herself up. The metal groaned under her
weight
, cold iron biting into her palms. Above her, Herrera's boots clanged against the grating. He moved with desperate energy, a man who knew what waited for him if he
was caught
. "Herrera! Stop!" He didn't. They never did. She climbed faster, her shoulders burning from the effort. The worn leather of her
watch
band rubbed against her wrist, a familiar irritation. She'd been
wearing that watch
the night Morris died. Three years now, and she still couldn't bring herself to replace it. The fire escape terminated at a rooftop access door. Herrera had already gone through, leaving it swinging on broken hinges. Quinn drew her weapon now—a building she didn't know, a suspect who might be armed. Procedure demanded caution. The door led not to a rooftop but down. A stairwell, far older than the building it served, stone steps worn smooth by what must have been centuries of foot traffic. Impossible. This building was Victorian at the oldest. Yet here were medieval stairs descending into darkness, lit only by what looked like phosphorescent moss clinging to the walls. Quinn hesitated at the threshold. Rain drummed against her back, a connection to the world she understood. Ahead lay something else entirely. Herrera's
footsteps
echoed
from below, growing fainter. She thought of Morris. Of the warehouse where they'd found him, his body unmarked but his face frozen in an expression of absolute terror. The coroner had ruled it a heart attack, but Morris had been thirty-four years old and ran marathons for fun. His heart had been perfect. There had been symbols on the warehouse walls. She'd photographed them before the scene
was cleared
, kept copies that she studied on sleepless nights. No one at the Yard would discuss them. Two detectives who'd asked too many questions had taken early retirement within the month. Quinn stepped through the door. The stairs wound downward in a tight spiral, taking her deeper than any basement should go. The air changed as she descended—warmer,
tinged
with unfamiliar scents. Spices she couldn't name. Something that might have been incense, or might have been smoke from a fire burning fuel that had never been wood. She counted the steps. Fifty. Seventy. At one hundred and twelve, the stairwell opened onto a landing. A heavy door stood before her, iron-banded oak that looked like it belonged in a castle. And standing beside it, a figure she hadn't noticed until she was almost on top of him—a gaunt man in a long coat, his skin pale to the point of translucence. "Detective." His voice was surprisingly pleasant. "You're a long way from your jurisdiction." "Metropolitan Police." She kept her weapon trained on him. "I'm pursuing a suspect. Step aside." The gaunt man smiled, revealing teeth that were
slightly
too sharp. "The market is neutral ground. We have rules here. No violence among the stalls, no badges honored, no warrants recognized." He tilted his head, studying her with eyes that reflected light like a cat's. "You can enter, Detective Quinn. Anyone can, if they know the way. But your authority ends at this door." "How do you know my name?" "We know everyone who takes an interest in our affairs. You've been
watch
ing The Raven's Nest for weeks. Did you think no one noticed?" He stepped aside, gesturing toward the door. "The man you're chasing saved a child's life last week. A little girl who would have died if he'd followed the rules your kind imposed on him. Is that the criminal you're so desperate to catch?" Quinn's jaw tightened. "I don't know what he did or didn't do. I know he's connected to people who've hurt others. I know he has answers about things I need to understand." "Then enter." The gaunt man pushed open the door. "But understand—what you find may not be what you expected. And some knowledge, once gained, cannot be unknown." The door swung wide, and Quinn saw what lay beyond. It was an underground station—she could still see the bones of it, the curved tunnel walls, the platform edge. But it had
been transformed
into something out of a fever dream. Stalls lined both sides of the platform, draped in fabrics of colors she'd never seen, displaying wares that defied description. Bottles that
seemed to
contain captured lightning. Books bound in leather that looked disturbingly like skin. Weapons that twisted the eye when you
tried to
focus on them. And people. Hundreds of them, moving between the stalls, conducting business in murmured voices. Some looked human. Others... didn't. A woman with moth wings folded against her back haggled with a vendor over what
appeared to
be a jar of preserved eyes. A massive figure, easily seven feet tall and covered in coarse hair, examined a selection of silver knives. Quinn's training screamed at her to retreat, to call for backup, to approach this through proper channels. But proper channels had failed her for three years. Proper channels had buried whatever
happened to
Morris under a mountain of sealed files and forced retirements. She spotted Herrera across the market, pushing through the crowd toward the far end of the platform. The Saint Christopher medallion around his neck caught the light from overhead lanterns—actual fire, she noted, not electric. He glanced back, saw her, and his face went pale. Quinn stepped through the door. The atmosphere hit her like a wave. Warmth, noise, the press of bodies and the overwhelming assault of unfamiliar smells. The gaunt doorkeeper had been right—she had no authority here. No backup, no radio contact, no way to call for help if things went wrong. She pushed forward anyway. The crowd parted for her,
slightly
. Word
seemed to
spread in ripples through the market—a detective, a badge, a representative of the world above intruding on this hidden space. Conversations died as she passed, only to resume in whispers behind her. She felt eyes on her from all directions, measuring her, assessing the threat she posed. Herrera had stopped running. He stood at the far end of the platform, near what must have once been a maintenance access. His hands were visible at his sides, and his expression had shifted from fear to something more complicated—resignation, maybe, mixed with a desperate hope. "You shouldn't have come down here," he said as she approached. His accent was faint, mostly buried under years in London, but she could hear Seville in the edges of his vowels. "This isn't a place for people like you." "People like me." Quinn kept her weapon at her side but didn't holster it. "And what kind of people are supposed to be here?" "People who've seen." He touched the scar on his left forearm—she'd read about it in his file, a knife attack during his paramedic days. "People who know what's
really
going on in this city. The things that happen after dark, in the spaces between what your reports can explain." "Then explain them to me." Herrera laughed, though there was no humor in it. "You've been trying to build a case. I've seen your surveillance teams outside the Nest, tracked your inquiries through NHS records. You think we're criminals. Drug dealers, maybe. Or something worse." He shook his head. "We're doctors, Detective. Not the kind your system recognizes, but doctors all the same. We help people your hospitals can't help. People your world refuses to acknowledge exist." "My partner died three years ago." The words came out before Quinn could stop them. "Crime scene looked like nothing I'd ever seen. No one would talk about it. No one would investigate." She took a step closer to Herrera. "I think you know something about what
happened to
him. I think the people you work for know a lot more." The market noise
seemed to
fade around them, creating a pocket of almost-silence. Herrera's warm brown eyes met hers, and she saw something shift in him—a decision
being made
. "Your partner," he said
slowly
. "DS Morris. He stumbled onto something he shouldn't have. Something that was never meant for human eyes." Herrera glanced around, lowering his voice. "The people I work with—they're not responsible for his death. But they know what is. They've been trying to stop it for a long time." "Stop what?" "Something that's coming, Detective. Something that's been building for years." He pulled the Saint Christopher medallion from beneath his shirt, holding it up so she could see the back. Symbols
were carved
there—the same symbols she'd photographed in that warehouse three years ago. "You want answers about Morris? You want to understand what's
really
happening in this city? Then you need to stop chasing us and start listening." Quinn stared at the medallion, at the symbols that had haunted her dreams for three years. The market swirled around them—impossible beings conducting impossible business in an impossible place beneath the streets of London. She holstered her weapon. "Talk," she said. "I'm listening."
created_at
"2026-02-17T02:47:54.797057+00:00"
2/17/2026, 2:47:54 AM
model
"anthropic/claude-4.5-opus-20251124"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1618
moderation_latency
(null)
generation_time
62609
tokens_prompt
914
tokens_completion
2807
native_tokens_prompt
917
native_tokens_completion
2491
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
0.06686
router
(null)
provider_responses
0
id
"msg_01YVxKADCwXxdnJPowCZqZW3"
status
200
is_byok
false
latency
1618
endpoint_id
"be883404-eb42-4b2d-b6e4-c7daa3aa8d62"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.5-opus-20251124"
api_type
"completions"
id
"gen-1771296411-hl9EvBUd2wqCzeJtYKRa"
upstream_id
"msg_01YVxKADCwXxdnJPowCZqZW3"
total_cost
0.06686
cache_discount
(null)
upstream_inference_cost
0
provider_name
"Anthropic"
Evaluation details
Result
Evaluator
Details
Meta Data
22.2222%
Adverbs in dialogue tags
Target: ≤10% dialogue tags with adverbs
totalTags
3
adverbTagCount
1
adverbTags
0
"he said slowly [slowly]"
72.7074%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
1832
totalAiIsmAdverbs
5
found
0
adverb
"slightly"
count
2
1
adverb
"slowly"
count
1
2
adverb
"really"
count
2
highlights
0
"slightly"
1
"slowly"
2
"really"
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)
78.1659%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
1832
totalAiIsms
4
found
0
word
"tinged"
count
1
1
word
"weight"
count
1
2
word
"footsteps"
count
1
3
word
"echoed"
count
1
highlights
0
"tinged"
1
"weight"
2
"footsteps"
3
"echoed"
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
123
matches
(empty)
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
1
hedgeCount
6
narrationSentences
123
filterMatches
0
"watch"
hedgeMatches
0
"seemed to"
1
"tried to"
2
"appeared to"
3
"happened to"
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
2
totalSentences
142
matches
0
"surveilling that bar"
1
"wearing that watch"
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
50
mean
36.28
std
23.42
cv
0.646
sampleLengths
0
52
1
15
2
11
3
66
4
77
5
45
6
48
7
45
8
2
9
5
10
44
11
38
12
59
13
22
14
7
15
49
16
46
17
5
18
51
19
64
20
13
21
15
22
64
23
6
24
67
25
32
26
27
27
10
28
79
29
60
30
43
31
45
32
5
33
45
34
4
35
56
36
46
37
40
38
24
39
49
40
5
41
72
42
61
43
29
44
53
45
2
46
68
47
34
48
4
49
5
100.0000%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
6
totalSentences
123
matches
0
"been stripped"
1
"was caught"
2
"was cleared"
3
"been transformed"
4
"being made"
5
"were carved"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
1
totalVerbs
242
matches
0
"was playing"
100.0000%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1402
adjectiveStacks
0
stackExamples
(empty)
adverbCount
36
adverbRatio
0.025677603423680456
lyAdverbCount
11
lyAdverbRatio
0.007845934379457917
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
142
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
142
mean
12.77
std
8.04
cv
0.629
sampleLengths
0
15
1
21
2
16
3
7
4
8
5
3
6
8
7
9
8
19
9
18
10
20
11
13
12
22
13
19
14
23
15
7
16
14
17
2
18
10
19
12
20
18
21
7
22
19
23
4
24
8
25
12
26
8
27
17
28
2
29
2
30
3
31
9
32
14
33
9
34
12
35
9
36
11
37
15
38
3
39
9
40
22
41
1
42
7
43
20
44
5
45
12
46
5
47
7
48
4
49
20
71.1268%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
4
diversityRatio
0.44366197183098594
totalSentences
142
uniqueOpeners
63
8.3333%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
3
fancyCount
2
fancyTags
0
"he said as she approached (say approach)"
1
"he said slowly (say slowly)"
85.4445%