Z.ai's frontier reasoning model for long-context agents and software engineering.
Anthropic's Mythos-class flagship for ambitious, long-running professional work.
No shared agent demos for these models yet.
No captured outputs for these models yet.
Based on the Capability Index, Claude Fable 5 scores higher (91.6 vs 83.4). However, "better" depends on your use case — pricing, speed, context window, and specific capability needs all matter.
GLM 5.2 has a lower blended cost. GLM 5.2: $0.78 input / $2.44 output. Claude Fable 5: $10.00 input / $50.00 output.
GLM 5.2 has a larger context window: GLM 5.2 supports 1M tokens vs Claude Fable 5 at 1M tokens.
Claude Fable 5 supports vision/image input, but GLM 5.2 does not.
Key differences: Claude Fable 5 has a notably higher capability index (8.2 point gap); GLM 5.2 is significantly cheaper; only Claude Fable 5 supports vision input. Compare full specs on this page.
If cost is your priority, choose the cheaper option. If you need the highest intelligence for complex tasks, pick the higher-scoring model. For long documents or codebases, choose the larger context window. You can try both GLM 5.2 and Claude Fable 5 for free on idapt.app to see which performs better for your specific needs.