Claude Sonnet 5.5 vs GLM 5.3 Prime
Claude Sonnet 5.5 took 3 min 49 s and $0.34 at list price, GLM 5.3 Prime took 55 min 49 s and $3.43 at list price. GLM 5.3 Prime took 15× as long and cost 10× as much.
Claude Sonnet 5.5
Anthropic · $10.00/M out · 9 HN pts
GLM 5.3 Prime
Z.ai · $8.80/M out
Only Claude Sonnet 5.5 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 three people in a workshop in Rotterdam, trying to keep old synthesizers alive. We repair, restore and recalibrate the instruments that shaped electronic music: Moogs and Oberheims, Rolands and Sequential Circuits, the odd temperamental Soviet oddity that someone found in an attic.
Most of what lands on our benches has been silent for years. A crackling pot, a drifting oscillator, a power supply that gave up in 1994. Some come from working musicians who need their instrument back before the next tour. Others come from people who inherited a dusty box from a parent and want to hear what it sounds like.
We work slowly and by hand. We trace faults with a scope and a schematic, source or rebuild parts when originals are gone, and change as little as we can. Every synth leaves with a note describing exactly what we did, so the next person to open it knows where we have been.
Come by, bring your synth, and stay for coffee.
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.
Specs and numbers
| Claude Sonnet 5.5 | GLM 5.3 Prime | |
|---|---|---|
| Maker | Anthropic | Z.ai |
| Made in | US | China |
| Released | 28 Sep 2026 | 23 Sep 2026 |
| Price in, per M tokens | $2.00 | $2.80 |
| Price out, per M tokens | $10.00 | $8.80 |
| Context | 1,000,000 tokens | 1,000,000 tokens |
| Weights | closed | closed |
| Hacker News points | 9 | — |
| Time for the six prompts | 3 min 49 s | 55 min 49 s |
| List price of the six prompts | $0.34 | $3.43 |
Claude Sonnet 5.5 was cheaper: $3.09 less at list price, and less on each of the 6 prompts. Claude Sonnet 5.5 was faster: 52 min 1 s less in total, and faster on each of the 6 prompts.
In the recording, both Breakout games play. GLM 5.3 Prime's landing page was cut off at the output limit (131,072 tokens).
Rebuild this screen experiment: Claude Sonnet 5.5's rebuild matched the screenshot at 94%; GLM 5.3 Prime was not in it. Tea Garden experiment: Claude Sonnet 5.5's game passed 5 of 5 checks; GLM 5.3 Prime was not in it.





