SceneCut AI · Issue #108 · Bake-off Episode 7

Same model.
Four brains.
Does thinking harder help?

One feature, written four times. AI coding models have a dial for how long they think before they write — and that thinking costs time and money. I ran the same job through Opus 4.8 at three thinking settings, plus a wildcard: Fable 5, Anthropic's newest model, deliberately set to barely think. Same starting code, same checklist of eight requirements. I checked every line of all four.

The scores are at the bottom. So is the part I didn't expect.

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i.The assignment

One tap, and the video decorates itself.

In plain English — SceneCut is a video-editing app I'm building. The feature I asked for is a one-tap "Premium" button: press it once and the app captions your scene, finds the nouns in what's being said, and pops a picture of each noun on screen exactly while that word is spoken. Each picture lands at a random spot in the prime area of the frame — the upper two-thirds, away from the edges — and gets a sound effect when it appears (and, optionally, when it disappears). Say "I bought a guitar in Tokyo" and a guitar and a skyline pop up, right on cue, with a little fwip. Eight requirements, checked one by one. Easy on paper. There's a reason it isn't.

ii.The export trap

It plays in the preview. Then it vanishes.

Here's the trap. Those sound effects have to be mixed into the real exported video — the file you actually share — not just the in-app preview. The export pipeline is the most delicate machinery in the app, with caching rules that decide when old rendered footage can be reused instead of rebuilt (rendering video is the slow part, so the app avoids redoing it). Wire a sound effect through the wrong path and it plays fine in the preview, then silently disappears from the exported file. No crash. No error. Your viewer just never hears it. The task named this trap out loud and demanded the real path — plus one subtle rule: swapping a sound (an audio change) must never trick the app into re-rendering the picture. So the real question wasn't "can you build the button." It was "can you push audio through the app's most delicate machinery without breaking what makes it fast."

⚠️ The trap. The failure mode makes no noise — literally. The sound plays in preview, the export looks done, and the shared file is missing audio. The only proof is reading the code and confirming the sound goes through the real export mix.
iv.How they were judged

Four separate reviews. Every claim checked.

Each entry got its own blind reviewer, walled off from the other three so nobody was swayed by a rival's work. Each reviewer pulled up the actual code, checked all eight requirements against what the code really does — pointing to the exact lines as proof — re-ran the automated tests itself, and fact-checked every claim in the entry's own write-up. Claiming something the code doesn't do is a major penalty. Score out of 100.

01

Read the task. List the eight requirements, and the export trap it warned about.

02

Pull up the real code. Check every claim against what the code actually does, line by line.

03

Re-run the tests. From scratch — never trust the "all passing" badge on the submission.

04

Score out of 100 against the checklist. Report every miss, with proof.

⚙️ A note on the judge — said out loud. The reviewers all ran on Fable 5 — and Fable 5 is also a contestant in this bake-off. Hold that thought. I'll put the receipts next to the result at the bottom — judge for yourself there.
v.The review rounds

Three passed on the first try. One was sent back.

Before any scoring, each entry went through a standard code review — the same gate any human engineer's work goes through. Three of the four were approved on their first pass. One was rejected and sent back for fixes, needing a repair round before it got through. I'm not telling you which one yet. What I can tell you: everyone cleared the hard parts. All four wired the sound effects through the real export mix — the exact trap the task warned about. All four got the placement math right, down to accounting for each image's width so it never pokes past the frame's safe zone. All four protected the caching rules, so an audio swap never forces a picture re-render. And all four wrote honest write-ups — my reviewers went hunting for inflated claims and found zero fabrications across the field. Which entry got sent back, and whether it recovered? That's at the bottom. It's the strangest part of the whole result.

vi.The paper trail

How much code did each brain write?

A quiet aside before the verdict — code volume is never part of the score, but hold these numbers in your head. The run set to think the least shipped the smallest change of the field. The everyday setting shipped the biggest — 354 lines more than the smallest.

EntryLines changedFilesFirst review
Fable 5 · low +1011 / −3
11
Opus 4.8 · xhigh +1078 / −3
11
Opus 4.8 · high +1127 / −0
11
Opus 4.8 · medium +1365 / −8
15 (most)
📐 Side note. Who got approved first pass — and who didn't — lands at the bottom, next to the scores.
The reckoning

So what did
thinking harder buy?

All four were scored against the task's eight requirements — every claim checked against the real code, all tests re-run. Three points cover the whole field, and the order is the story.

Counting down, from fourth place…

— Fourth place —
Opus 4.8high Yes — high effort came last. The run itself is solid: sound wired through the real export mix, placement math correct, honest write-up. Three things kept it here. On scenes with multiple clips it only reads the first one, so later nouns never get pictures. A half-second minimum keeps each picture up past short words instead of matching the word exactly. And the picture-sourcing piece shipped as a placeholder — a colored square where the real image should be.
90/100
The Enhance screen Opus 4.8 on high effort built: a sheet with checkboxes for sound when an image appears or disappears, each with a sound picker and preview button, and an Enhance Scene button.
The screen this entry shipped
— Third place —
Fable 5low ★ The wildcard, barely trying, beat Opus on high — in the smallest change of the whole field. Full transcription, real export mix, clean placement. What kept it here: a 1.2-second minimum display time stretches pictures past the word being spoken (a soft bend of one requirement, not a break), and on multi-clip scenes the appear-sound fires only once. Its write-up also miscounted one small check result — the only smudge my reviewers found on it.
91/100
The Enhance screen Fable 5 on low effort built: the scene video with play controls, a one-line description, compact sound-toggle checkboxes with sound pickers, and an Enhance button.
The screen this entry shipped
— Second place —
Opus 4.8medium The everyday setting beat the high one. All eight requirements met, and the field's best work on the caching rules — the machinery that keeps exports fast — bought with the biggest change of the bake-off. What kept it from the top: it never verified the export on a real device, and it rebuilt the sound-picker from scratch instead of reusing the one the app already had.
92/100
The Enhance screen Opus 4.8 on medium effort built: a full-screen sheet with a plain-language description, switch toggles for appear and disappear sounds with named sound choices, and an Enhance button.
The screen this entry shipped
— First place —
Maximum thinking wins.
Barely.

The dial's top setting takes it at 93 — two points above the wildcard that barely tried.

Opus 4.8 · xhigh
Anthropic · Claude Code · dial at maximum
93 /100
The Enhance screen the winner, Opus 4.8 on extra-high effort, built: the scene video with play controls, a one-line description, sound-toggle checkboxes with sound pickers, and an Enhance button.
The screen the winner shipped

The deepest correctness work in the field. All eight requirements met, plus the things nobody asked for by name: handling a cancelled run cleanly mid-generation, checking the user's credit balance before spending it, surviving a partial failure without corrupting the scene. Twelve new automated tests. Its soft spots are small — a simplified sound-timing model on multi-clip scenes, and no verification on a physical device.

And now the twist from section v: the winner was the only entry sent back for fixes. The other three — including the wildcard that barely tried — sailed through review on their first pass. Maximum thinking produced the best final code and the only first-draft rejection. So I went back and blind-scored the pre-fix first draft on its own: 90/100 — a tie for last place. The repair round (a spending pre-check, clean cancellation mid-run, and the review's other findings) is worth the full three points between last and first. The 93 is earned — but on first drafts alone, the laziest run's 91 wins the whole thing.

⚖️ About the judge — read before trusting the result I judge with Fable 5. Fable 5 was also a contestant. Here's why that runs against me this time: Fable 5's entry placed third, at 91 — the judge did not crown itself. Extra safeguards: each entry got its own separate blind reviewer, so no reviewer ever compared its own model's work against a rival's. And little of this is a matter of taste — either the sound goes through the real export mix, or it doesn't; either the tests pass when re-run, or they don't. Pull up the code and check.

The headline isn't who won — it's that four brains finished three points apart, with the settings out of order: medium beat high, high came last, and maximum thinking beat barely-trying by two points. If you're paying for the top of the dial on every task, this test says the everyday setting gets you within a couple points of the same answer.

Summary

All four, at a glance.

Anthropic · Claude Code
Opus 4.8
Winner
Score
93 /100
Thinking
xhigh (maximum)
Review rounds
1 — the only one sent back
Verdict
Deepest correctness work · 12 new tests · only first-draft rejection · +1078 / −3 across 11 files
Anthropic · fableplan
Opus 4.8
Score
92 /100
Thinking
medium (everyday)
Review rounds
0 — first-pass approval
Verdict
Best caching work · biggest change of the field · no on-device export check · +1365 / −8 across 15 files
Anthropic · Claude Code · debut ★
Fable 5
Score
91 /100
Thinking
low (barely trying)
Review rounds
0 — first-pass approval
Verdict
Smallest change · beat Opus-high · pictures linger past their word · single-fire sound on multi-clip scenes · +1011 / −3 across 11 files
Anthropic · Claude Code
Opus 4.8
Score
90 /100
Thinking
high
Review rounds
0 — first-pass approval
Verdict
Last place at high effort · first-clip-only transcription · picture sourcing left as a placeholder · +1127 / −0 across 11 files
Epilogue — what shipped

Nothing's merged — yet.

As of scoring, none of the four entries has been merged in. All four (#109, #110, #111, #112) sit side by side on the open issue. The one genuinely unresolved question is a product decision, not a code one: where should the noun pictures come from — AI-generated images, or a stock-photo search? That call is still pending, and every entry built the feature so either answer can plug in later.