GLM 5.3 Prime vs Claude Fable 5.1
GLM 5.3 Prime took 55 min 49 s and $3.43 at list price, Claude Fable 5.1 took 16 min 4 s and $3.97 at list price. GLM 5.3 Prime took 3.5× as long, and Claude Fable 5.1 cost 1.2× as much.
GLM 5.3 Prime
Z.ai · $8.80/M out
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.
Some of the machines we work on were built before any of us were born. Patchbay is a three-person repair studio in Rotterdam, and what we do is simple to describe: we keep vintage synthesizers playing. A Minimoog that sat in an attic for thirty years. A Juno-60 with keys that no longer speak. A modular system that hums where it should roar. Whatever comes through our door gets opened up, traced through, and brought back.
That means rebuilding power supplies, cleaning a thousand key contacts, chasing a fault across three boards until it turns out to be a single cracked solder joint. It means calibrating oscillators that have drifted for decades, and listening — really listening — until a filter sounds the way it did the day it left the factory.
We do this because these instruments still sound like nothing else, and because somewhere a player is waiting to hear one come back to life.
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
| GLM 5.3 Prime | Claude Fable 5.1 | |
|---|---|---|
| Maker | Z.ai | Anthropic |
| Made in | China | US |
| Released | 23 Sep 2026 | 1 Sep 2026 |
| Price in, per M tokens | $2.80 | $10.00 |
| Price out, per M tokens | $8.80 | $50.00 |
| Context | 1,000,000 tokens | 1,000,000 tokens |
| Weights | closed | closed |
| Hacker News points | — | 1,630 |
| Time for the six prompts | 55 min 49 s | 16 min 4 s |
| List price of the six prompts | $3.43 | $3.97 |
GLM 5.3 Prime was cheaper: $0.55 less at list price, and less on 3 of the 6 prompts. Claude Fable 5.1 was faster: 39 min 45 s less in total, and faster on each of the 6 prompts.
In the recording, GLM 5.3 Prime's Breakout game plays; Claude Fable 5.1's stopped painting. GLM 5.3 Prime's landing page was cut off at the output limit (131,072 tokens).
Rebuild this screen experiment: Claude Fable 5.1's rebuild matched the screenshot at 78%; GLM 5.3 Prime was not in it. Tea Garden experiment: Claude Fable 5.1's game passed 5 of 5 checks; GLM 5.3 Prime was not in it.





