Vol. I · No. 1 · MMXXVI
NextChapterBench A Benchmark of Literary Continuation
13 models · 10 items · 3 judges

The Standings → Claude Opus 5 (medium)

Live run data

Anthropic

Claude Opus 5 (medium)

medium reasoning effort · via Claude CLI · judged by Fable 5 and Gemini 3.7 Flash and GPT-5.6 Sol · not the setting shown on the standings; also run at high0.78

Results from run ‘first’: ten items, 30 verdicts.

Headline 0.766 compliance × craft
Compliance 0.962 of 1.0
Craft 0.796 of 1.0

The record: 10 items · 30 verdicts · 0 errors · 2,433 words on average · est. generation cost $1.34

Read the chapters in full

§ I

Craft by Dimension

Six dimensions, each marked 1–5, averaged over ten items and all judges.

Mean craft mark by dimension · 30 verdicts, run ‘first’

Voice
4.27
Prose
4.10
Character
4.10
Scene
4.17
Integration
4.47
Momentum
4.00
12345
craft mark, 1–5; bars begin at the scale’s floor of 1

Integration is the strongest dimension (4.47); momentum the weakest (4.00). Hover or focus a bar for the per-judge means.


§ II

The Three Judges, per Item

Each item receives one verdict from each judge; the spread of the dots is the disagreement.

Headline score per item, by judge · run ‘first’

Fable 5 Gemini 3.7 Flash GPT-5.6 Sol
The Awakening
The Secret Garden
Dracula
Red Harvest
Persuasion
The Mysterious Affair at Styles
The Moonstone
The War of the Worlds
The Sun Also Rises
Leave It to Psmith
00.250.500.751.00
headline = compliance × craft, 0–1, one verdict per judge
The same ten items in figures, with word counts.
Item Headline Fable 5 Gemini 3.7 Flash GPT-5.6 Sol Words
The Awakening item 016 · after ch. 7 · Kate Chopin 0.820.750.920.791,674
The Secret Garden item 013 · after ch. 2 · Frances Hodgson Burnett 0.810.791.000.642,341
Dracula item 015 · after ch. 5 · Bram Stoker 0.790.710.950.712,397
Red Harvest item 023 · after ch. 2 · Dashiell Hammett 0.780.750.790.792,481
Persuasion item 001 · after ch. 1 · Jane Austen 0.780.830.710.792,519
The Mysterious Affair at Styles item 017 · after ch. 3 · Agatha Christie 0.770.750.830.712,438
The Moonstone item 011 · after ch. 8 · Wilkie Collins 0.760.750.790.752,900
The War of the Worlds item 006 · after ch. 1 · H. G. Wells 0.730.710.640.832,587
The Sun Also Rises item 021 · after ch. 3 · Ernest Hemingway 0.720.750.790.622,315
Leave It to Psmith item 022 · after ch. 3 · P. G. Wodehouse 0.700.640.830.642,675

  The widest judge split in the run: Gemini 3.7 Flash 1.00 against GPT-5.6 Sol 0.64 on The Secret Garden (item 013).


§ III

Length Against the Brief

Words written per item, against each brief’s maximum.

Word count per item vs. brief maximum · run ‘first’

words written brief maximum
The Awakening
1,674
The Secret Garden
2,341
Dracula
2,397
Red Harvest
2,481
Persuasion
2,519
The Mysterious Affair at Styles
2,438
The Moonstone
2,900
The War of the Worlds
2,587
The Sun Also Rises
2,315
Leave It to Psmith
2,675
08001,6002,4003,200
words; the ink tick marks each brief’s maximum

Nine of ten items landed inside their brief’s word range. The Moonstone ran over by 100 words.


§ IV

Worst Flaws, as Recorded

Each verdict names the chapter’s single worst flaw, with evidence. Quoted verbatim from run ‘first’.

Much of the chapter's best material is closely adapted or lifted from Burnett's actual Chapter 3 (the station arrival, the studded oak door, the wind-in-the-corridors speech), so the strongest passages are borrowed rather than invented, and the few original lines — like Mrs. Medlock's snappish \"It sounds like whatever I say it sounds like\" — dip below the period register.

on The Secret Garden, item 013 · Fable 5

Its strongest passages lean on near-verbatim transcription of Hemingway's actual Chapter 4 (the taxi-route paragraph, the hard-boiled-in-the-daytime reflection), so the chapter's best effects are borrowed rather than invented, and the genuinely original moments occasionally over-state what should stay implicit ("and that she knew it").

on The Sun Also Rises, item 021 · Fable 5

The chapter silently elides roughly four hours between the morning-room confrontation and the eleven-o'clock examination (including Poirot's entire off-page interview with Mary), and in doing so also loosens the required closing image, since the shred ends buttoned away in Poirot's pocket rather than lying between the two men.

on The Mysterious Affair at Styles, item 017 · Fable 5

The chapter introduces severe continuity contradictions with Chapter 1 by placing the fall on the night of the twelfth and having the narrator claim he had not thought of Mars, ignoring both the ten-night launch sequence with its interplanetary transit and the narrator's own telescopic vigil with Ogilvy.

on The War of the Worlds, item 006 · Gemini 3.7 Flash

§ V

The Mechanical Docket

Automated screening results across the ten outputs.