GLM-5 is the open-weight model built specifically for the work Codex targets: agentic engineering and long-horizon coding. Z.ai's 744B MoE led the open-weights intelligence index at launch and performs strongly inside popular harnesses like Claude Code, Cline and Roo Code, with open weights you can self-host to slash costs.
Codex (GPT-5.2-Codex) is the premium, closed alternative. It is strong at large refactors, migrations, Windows support and security-aware automation, with deep ChatGPT integration. Codex leads on the hardest engineering and consistency; GLM-5 delivers a large share of that agentic capability at open-weight prices. For budget-conscious or self-hosted teams, GLM-5 is the standout; for maximum reliability on big tasks, Codex holds the edge.
Which should you choose?
GLM-5
GLM 5 · 204K context
Pick it if
you want top open-weight agentic coding you can self-host.
Codex (GPT-5.2-Codex)
GPT-5.2-Codex · 400K context
Pick it if
you need the strongest large-scale, security-aware engineering.
Codex leads on top-end refactors, migrations and security automation; GLM-5 offers strong agentic coding with open weights at far lower cost. Choose by budget and your need to self-host.
Questions
Is GLM-5 good for coding agents?
Yes. It's tuned for agentic engineering and shines in harnesses like Claude Code and Cline, at open-weight prices.
Can GLM-5 match Codex?
On everyday agentic coding it gets close and is far cheaper; Codex still leads on the largest, hardest engineering tasks.