GLM 5.2 is TOO GOOD! (Better than Opus 4.8)

GLM 5.2 is a text-only coding model that recreates the Astro homepage, builds a 3D Chinese pavilion, and ships a working space shooter from prompt alone — and it does this without burning a GPU cluster.

Specs and pricing

GLM 5.2 keeps the 744 billion parameter mixture of experts backbone from GLM 5.1 with about 40 billion parameters active per token, but the context window jumps from roughly 200,000 to 1 million tokens. The MoE design keeps inference cost close to a 30 or 40 billion dense model, which is why the creator is running it on Cloud Code without complaining about the bill. The team burned 100% of the 5-hour quota in one session on three long-running tasks.

Benchmark deltas vs GLM 5.1

Terminal Bench 2.0 scored a nearly 20-point increase over GLM 5.1. SWE-bench (the transcript's "Deep Suey") hit 46.2, a 3x jump. Z.ai is positioning the model against Opus 4.8 and GPT 5.4, not Fable 5, which the creator reads as a signal that this is not a distilled Fable 5 despite the close release timing.

Test 1 — Astro homepage clone

From a text spec generated by Kimmi 2.7 code (vision model used to extract the design brief), GLM 5.2 produced a site with a different color palette but "the UI, the UX as well, it feels very, very similar to using the Astro website." The single-shot prompt path is the key win: no screenshot handoff, no manual file jumping.

Test 2 — 3D Chinese architecture

GLM 5.2 completed the roof, which most older models fail at, but floating pillars remain. The agent self-flagged that it could not run a headless browser, so "the WebGL render itself is unverified at runtime" — three.js API calls, shader injection, and geometry passed syntax checks only. Quinn 3.7 max and Fable 5 are still the only models producing a polished, scaffolding-free roof.

Test 3 — Space shooter game

Physics, blast effects, chain attacks, and a hidden end-game boss at 100,000 score all worked. Movement is locked to forward-facing only, where Kimmi 2.6 already supports 360-degree rotation. Creator calls it a "pass" because the dopamine from the explosions outweighs the missing rotation.

Who should care

If you are a vibe coder who defaults to one-shot natural-language prompts and skips screenshots, GLM 5.2 is the current best text-only option. If you need 3D or full game-engine polish, Fable 5 still wins on a single shot.