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Run: 2026-02-17-01KHMR3MNZF4DENHT3RJQ7ETK7
Run Details
Model:
Claude Opus 4.6
Test:
Bad Writing Habits
Scenario:
Thriller: chase through city streets
Duration:
1m 12s
Cost:
$0.067915
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 into a blur of neon and wet stone. Harlow Quinn hit the pavement hard with each stride, her boots slapping through puddles that reflected the city back at her in broken fragments. Ahead, maybe forty meters, Tomás Herrera cut left off Dean Street, his dark jacket disappearing around the corner like a fish darting into a reef. She keyed her radio without slowing. "Suspect heading north on Bateman Street toward Soho Square. Male, five-ten, olive complexion, dark curly hair, dark jacket. Moving fast." Static answered her. The radio had been cutting in and out for the last three minutes, ever since Herrera had bolted from the doorway beneath that green neon sign. The Raven's Nest. She'd been
watch
ing the place for two weeks, sitting in a borrowed Peugeot across the street with cold coffee and a telephoto lens, cataloging every face that slipped through its door. Herrera's face had come up in three separate inquiries — two missing persons cases and a narcotics investigation that had gone sideways when the seized substances couldn't be identified by any lab in the Met's network. The analysts had called them "organic compounds of unknown origin," which was bureaucratic shorthand for nobody has a bloody clue. Quinn rounded the corner. The rain was in her eyes, streaming down from her closely cropped hair into the collar of her jacket. She blinked it away and spotted him — Herrera, thirty meters ahead now, glancing back over his shoulder. Even at this distance, through the rain and the dark, she could see his expression. Not panicked. Calculated. He
was deciding
something. He cut right, vanishing into the mouth of an alley. Quinn's legs burned. She was forty-one and in shape, but eighteen years of service had put mileage on her knees that no amount of gym work could fully repair. She pushed through it, focusing on the rhythm of her breathing, the metronomic precision that her body still remembered from her army days. In, out. Feet striking the ground with military efficiency. Close the gap. The alley was narrow, flanked by the backs of restaurants. Kitchen exhaust fans roared overhead, pumping out steam that mixed with the rain and turned the passage into something that felt tropical and wrong. Bins overflowed with black bags. A cat screamed somewhere and bolted across her path, a grey streak of panic. At the end of the alley, a door stood open. Industrial. Metal. Leading down. She stopped at the threshold, chest heaving, and looked at the stairs descending into fluorescent light. They
were tiled
— white ceramic, the old London Underground style, scalloped and institutional. Some of the tiles were cracked. Others
were missing
entirely, exposing the dark brick beneath like wounds in pale skin. She knew this area. There was no active Tube station here. The closest was Mornington Crescent, and that was a fifteen-minute walk north. But London
was riddled
with ghost stations, sealed platforms, forgotten tunnels — the city's underground skeleton, vast and unmapped. Quinn checked her radio again. Dead now. Not even static. She turned it off and on. Nothing. She pulled her phone from her jacket's inner pocket. No signal. The screen showed the time — 11:47 PM — and nothing else. No bars, no data connection, as if she'd stepped into a dead zone. She looked down the staircase. Somewhere below, she could hear
footsteps
, rapid and receding, and something else — a low hum, almost subliminal, like the vibration of a massive engine buried deep in the earth. And beneath that, layered and strange, the murmur of voices. Many voices. A crowd. Her left hand went to the worn leather of her
watch
strap, a habit she'd developed three years ago. She'd been wearing this
watch
the night DS Morris died. The night they'd followed a lead into a warehouse in Rotherhithe and Morris had gone through a door and simply not come back. Not dead, the investigation concluded. Missing. The door had led to a storage room with no other exits, and Morris had walked through it and ceased to exist. The case was still open. It would always be open, as far as Quinn
was concerned
. She thought about Morris now, standing at the top of another staircase leading into another unknown space. Morris, who'd been braver than her and paid for it. Morris, who'd have already been halfway down these stairs, turning back to say come on, Quinn, don't be a pensioner about it. The
footsteps
below were almost gone. Quinn unholstered her weapon and started down. The stairs went deeper than they should have. Three flights, then four, the fluorescent tubes giving way to something warmer and more erratic — oil lamps, she realized, mounted in iron brackets on the tunnel walls. The tiles
were gone
now, replaced by exposed Victorian brickwork, and the air changed, growing warmer, drier, carrying scents that didn't belong underground: cardamom, ozone, something metallic and sweet like heated copper. At the bottom of the fifth flight, the tunnel opened. Quinn stopped. Her weapon hand dropped
slightly
, not from any decision but from the sheer disorientation of what she
was seeing
. The space was enormous. It occupied what had clearly once been a Tube platform, but it had
been transformed
into something that looked like a cross between a Moroccan souk and a Victorian curiosity shop, extended laterally into side tunnels and former service corridors until the whole thing became a sprawling underground bazaar. Stalls lined both sides of the platform, draped in fabrics of deep crimson and indigo, hung with lanterns that burned with flames in colors she couldn't name — not quite blue, not quite violet, shifting in ways that made her eyes water if she looked too long. The old platform signage was still visible in places: CAMDEN TOWN, it read, except the letters
flickered
as if they couldn't quite hold onto their meaning. This wasn't the Camden Town station she knew. This was something underneath it. Something else entirely. The crowd was dense and diverse in ways that made Quinn's trained eye for identification short-circuit. Some of the people moving between the stalls looked
perfectly
ordinary — Londoners in coats and jeans, haggling over goods she couldn't identify from this distance. Others were less ordinary. A woman with skin like polished obsidian and pupils that reflected light the way a cat's did. A man who was too tall by at least a foot and a half, his joints bending at angles that made Quinn's stomach
lurch
. A child — or something shaped like a child — carrying a cage that contained a small,
luminous
bird that sang in harmonics that pressed against her sinuses. No one had noticed her yet. Or if they had, they didn't care. She spotted Herrera. He was fifty meters ahead, moving through the crowd with the ease of someone who knew this place. He'd slowed to a walk, weaving between stalls, pausing briefly to exchange words with a vendor selling what looked like bottled smoke arranged by color on
velvet
-lined shelves. Quinn saw him reach beneath his shirt and pull out something — his Saint Christopher medallion, she recognized it from surveillance photos — and show it to the vendor, who nodded and gestured toward one of the side tunnels. Quinn pressed herself against the nearest wall, tucking into the shadow of a stall that
appeared to
be selling old books bound in leather that moved subtly under the lamplight, as if something breathed within the covers. She assessed. No radio. No phone. No backup. She
was carrying
her standard-issue Glock 17 with fifteen rounds and one in the chamber, which felt absurdly inadequate in a place where the laws of physics
seemed to
be more like guidelines. She had no jurisdiction here — she wasn't even sure here existed in any way that the Crown Prosecution Service would recognize. But Herrera
was connected
to three open cases. He'd run when she'd shown her warrant card at the Raven's Nest. People who ran had reasons, and those reasons lived in the space between what they'd done and what they were afraid of
being caught
for. Whatever this place was — drug market, arms bazaar, something she didn't have a category for — Herrera moved through it like a man with standing. He wasn't a tourist. He was a regular. She thought about the narcotics report again. Organic compounds of unknown origin. She thought about the missing persons — both of them last seen in Camden, both of them connected to the same network of unlicensed medical practitioners that Herrera's name kept surfacing in. Banned alchemical substances, one informant had called them, and Quinn had written it off as street slang. She
wasn't writing
it off anymore. Herrera disappeared into the side tunnel. Quinn checked her weapon. Safety off. She adjusted her grip, felt the familiar
weight
settle into her palm, and stepped into the crowd. The market swallowed her. Bodies pressed close, and the noise was extraordinary — a dozen languages she recognized and half a dozen she didn't, layered over the chiming of small bells, the hiss of something
being poured
from vessel to vessel, the low rhythmic chanting from a stall where an old man sat cross-legged on a rug that hovered an inch above the platform floor. Someone jostled her elbow and she spun, hand going to her holstered weapon, but it was just a woman carrying an armful of dried flowers that smelled like burnt sugar and whispered when the air moved through them. Quinn kept moving. She kept Herrera's last known trajectory fixed in her mind and
navigated
toward the side tunnel, keeping her head down, her sharp jaw set, her brown eyes cataloging everything with the obsessive precision that had earned her three commendations and a reputation for being impossible to work with. She reached the side tunnel. It was narrower than the main platform, lit by a single string of those strange not-quite-violet lanterns, and it curved away to the left. Footsteps
echoed
from within. One set. Herrera. Quinn looked back at the market behind her. At the stalls and the impossible people and the ceiling where the old Tube tunnel arched overhead, decorated now with painted constellations she didn't recognize, glowing faintly with their own light. She should go back. Call it in. Bring a team. Do this properly. But she thought of Morris. She thought of the warehouse door and the empty room and the three years of nothing that followed. She thought of the look on Morris's wife's face at the memorial service, the way grief and confusion had blended into something worse than either — the not knowing, the open wound that refused to scar. The cases connected to Herrera had that same shape. People who vanished. Explanations that didn't explain. A gap in the world where the truth should be, and everyone pretending the gap wasn't there. Quinn straightened. She checked the worn leather
watch
on her wrist — a reflex, a ritual, a promise she'd made to a partner who'd walked into the dark and never come back. Then she walked into the tunnel after Herrera, and the market noise closed behind her like water over a stone.
created_at
"2026-02-17T02:51:54.316665+00:00"
2/17/2026, 2:51:54 AM
model
"anthropic/claude-4.6-opus-20260205"
app_id
182717
external_user
(null)
streamed
true
cancelled
false
latency
1625
moderation_latency
(null)
generation_time
72247
tokens_prompt
914
tokens_completion
2855
native_tokens_prompt
918
native_tokens_completion
2533
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
0.067915
router
(null)
provider_responses
0
id
"msg_011DcA85fytnX4aXV5ArjVP6"
status
200
is_byok
false
latency
1625
endpoint_id
"c926c048-563e-44b0-8434-95965bee924c"
provider_name
"Anthropic"
model_permaslug
"anthropic/claude-4.6-opus-20260205"
api_type
"completions"
id
"gen-1771296641-Tet9eZ59nWIQhxvRqpXZ"
upstream_id
"msg_011DcA85fytnX4aXV5ArjVP6"
total_cost
0.067915
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
1
adverbTagCount
0
adverbTags
(empty)
89.3162%
AI-ism adverb frequency
Target: <1% AI-ism adverbs (57 tracked)
wordCount
1872
totalAiIsmAdverbs
2
found
0
adverb
"perfectly"
count
1
1
adverb
"slightly"
count
1
highlights
0
"perfectly"
1
"slightly"
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)
41.2393%
AI-ism word frequency
Target: <1% AI-ism words (140 tracked)
wordCount
1872
totalAiIsms
11
found
0
word
"luminous"
count
1
1
word
"lurch"
count
1
2
word
"flickered"
count
1
3
word
"velvet"
count
1
4
word
"calculated"
count
1
5
word
"weight"
count
1
6
word
"footsteps"
count
3
7
word
"echoed"
count
1
8
word
"navigated"
count
1
highlights
0
"luminous"
1
"lurch"
2
"flickered"
3
"velvet"
4
"calculated"
5
"weight"
6
"footsteps"
7
"echoed"
8
"navigated"
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
140
matches
(empty)
100.0000%
Filter word density
Target: ≤12% sentences with filter/hedge words
filterCount
2
hedgeCount
2
narrationSentences
140
filterMatches
0
"watch"
hedgeMatches
0
"appeared to"
1
"seemed to"
100.0000%
Overuse of "that" (subordinate clause padding)
Target: ≤10% sentences with "that" clauses
thatCount
0
totalSentences
141
matches
(empty)
100.0000%
Paragraph length variance
Target: CV ≥0.5 for paragraph word counts
totalParagraphs
40
mean
47.1
std
32.95
cv
0.7
sampleLengths
0
65
1
26
2
119
3
63
4
10
5
64
6
53
7
14
8
50
9
42
10
53
11
49
12
96
13
49
14
6
15
7
16
68
17
10
18
21
19
126
20
16
21
115
22
13
23
3
24
85
25
37
26
63
27
79
28
67
29
6
30
23
31
103
32
51
33
36
34
39
35
13
36
59
37
33
38
32
39
20
95.2381%
Passive voice overuse
Target: ≤5% passive sentences
passiveCount
8
totalSentences
140
matches
0
"were tiled "
1
"was riddled"
2
"was concerned"
3
"were gone"
4
"been transformed"
5
"was connected"
6
"being caught"
7
"being poured"
100.0000%
Past progressive (was/were + -ing) overuse
Target: ≤10% past progressive verbs
pastProgressiveCount
5
totalVerbs
307
matches
0
"was deciding"
1
"were missing"
2
"was seeing"
3
"was carrying"
4
"wasn't writing"
100.0000%
Purple prose (modifier overload)
Target: <4% adverbs, <2% -ly adverbs, no adj stacking
wordCount
1846
adjectiveStacks
0
stackExamples
(empty)
adverbCount
54
adverbRatio
0.02925243770314193
lyAdverbCount
14
lyAdverbRatio
0.007583965330444204
100.0000%
Repeated phrase echo
Target: ≤20% sentences with echoes (window: 2)
totalSentences
141
echoCount
0
echoWords
(empty)
100.0000%
Sentence length variance
Target: CV ≥0.4 for sentence word counts
totalSentences
141
mean
13.36
std
12.09
cv
0.905
sampleLengths
0
16
1
24
2
25
3
6
4
20
5
3
6
26
7
3
8
31
9
36
10
20
11
4
12
19
13
18
14
15
15
2
16
1
17
4
18
10
19
3
20
26
21
23
22
2
23
7
24
3
25
10
26
24
27
5
28
14
29
10
30
1
31
1
32
2
33
16
34
14
35
6
36
14
37
4
38
7
39
12
40
19
41
5
42
2
43
3
44
6
45
1
46
9
47
2
48
12
49
13
54.8463%
Sentence opener variety
Target: ≥60% unique sentence openers
consecutiveRepeats
16
diversityRatio
0.3971631205673759
totalSentences
141
uniqueOpeners
56
0.0000%
Dialogue tag variety (said vs. fancy)
Target: ≤30% fancy dialogue tags
totalTags
1
fancyCount
1
fancyTags
0
"The analysts had called them which was bureaucratic shorthand for nobody has a bloody clue. (call be have)"
87.0965%