Mercury 3 vs Claude Fable 5.1
Mercury 3 took 7 min 31 s and $0.065 at list price, Claude Fable 5.1 took 16 min 4 s and $3.97 at list price. Claude Fable 5.1 took 2.1× as long and cost 62× as much.
Mercury 3
Inception · $0.35/M out · 258 HN pts
Claude Fable 5.1
Anthropic · $50.00/M out · 1,630 HN pts
Only Claude Fable 5.1 has CLI runs here (Claude Code).
Pelican
Generate an SVG of a pelican riding a bicycle
Watch
Draw a mechanical wristwatch that shows the current local time, with a sweeping seconds hand and a date window. Make it look expensive.
Landing
Build the landing page for Lumen Cycles, a Copenhagen workshop that builds custom cargo bikes to order. Make it look like a real brand you would trust with 4,000 euros.
Breakout
Make a Breakout game I can play right now with the keyboard or the mouse. Give it several levels, a score and some juice.
Logo
Design a logo for Night Heron, an independent bookshop that only opens after dark.
About
Write the opening of the About us page for Patchbay, a three-person studio in Rotterdam that repairs vintage synthesizers. About 150 words.
Patchbay is a three-person repair studio in Rotterdam, tucked between a bike shop and a coffee roastery, where vintage synthesizers come to live another life. We are not a factory and we are not a museum; we are technicians who love the smell of warm solder and the patience that old circuits demand. Between us we have restored everything from early Moog modulars to battered Junos, and we treat each instrument as if it were the first one we ever opened. There is no assembly line here. Every capacitor is tested, every busbar tracked by hand, and every voice board is listened to twice—once on the bench, once through the speakers of the synth that will use it. Patchbay exists because these machines deserve more than a quick fix. They deserve someone who knows their quirks, their failures, and the strange, beautiful sounds that made us fall in love with them in the first place.
Patchbay is three people and one workshop in Rotterdam, and we spend our days bringing old synthesizers back to life. Most of what arrives at our bench is somewhere between thirty and fifty years old: a Juno with a dead voice chip, a Minimoog that drifts out of tune the moment the room warms up, a Polysix whose battery has quietly eaten its own circuit board. We know these instruments inside and out because we have had hundreds of them open on the table.
We started Patchbay because we kept meeting musicians who had been told their synth was not worth fixing. We disagree. These machines were built to be serviced, and with the right parts, enough patience, and a good set of schematics, almost any of them can be made to play again. When we hand an instrument back, we want it to sound the way it did the day it left the factory, or better.
Specs and numbers
| Mercury 3 | Claude Fable 5.1 | |
|---|---|---|
| Maker | Inception | Anthropic |
| Made in | US | US |
| Released | 16 Oct 2026 | 1 Sep 2026 |
| Price in, per M tokens | $0.10 | $10.00 |
| Price out, per M tokens | $0.35 | $50.00 |
| Context | 1,000,000 tokens | 1,000,000 tokens |
| Weights | closed | closed |
| Hacker News points | 258 | 1,630 |
| Time for the six prompts | 7 min 31 s | 16 min 4 s |
| List price of the six prompts | $0.065 | $3.97 |
Mercury 3 was cheaper: $3.91 less at list price, and less on each of the 6 prompts. Mercury 3 was faster: 8 min 34 s less in total, and faster on 4 of the 6 prompts.
In the recording, both Breakout games stopped painting.
Rebuild this screen experiment: Claude Fable 5.1's rebuild matched the screenshot at 78%; Mercury 3 was not in it. Tea Garden experiment: Claude Fable 5.1's game passed 5 of 5 checks; Mercury 3 was not in it.





