# GLM 5.3 ID appears in OpenRouter's catalog at 1M context

> The ID `z-ai/glm-5.3` showed up in OpenRouter's public model-list API on 2026-08-21, listed at 1,048,576 context. Catalog observation only — no Z.ai announcement was checked, and the entry could be a test or placeholder.

| | |
|---|---|
| **Tool** | Z.ai |
| **Version** | — |
| **Kind** | announcement |
| **Published** | unknown |
| **Observed** | 2026-08-21 |
| **Significance** | 3/5 |
| **Breaking** | no |
| **Categories** | new-model, model-support, context-window |

> **Note:** this classification is below our confidence threshold and is pending human review.

## What changed


- Model ID: `z-ai/glm-5.3`
- Catalog name: Z.ai: GLM 5.3
- Listed context length: 1,048,576
- Source endpoint: `https://openrouter.ai/api/v1/models`
- First seen 2026-08-21; absent from the prior read
- Not a vendor announcement — treat as a trace, not a shipped product fact


## Sources

- [api_models_endpoint](https://openrouter.ai/api/v1/models) — retrieved 2026-08-21


## Community

_No curated reactions recorded. Facts and community takes are kept in separate layers
and never blended._

---
Canonical: https://changelogs.info/zai/glm-5-3-id-appears-in-openrouter-s-catalog-at-1m-context
Entity: https://changelogs.info/zai
Event ID: `evt_2026-08-21_zai_new-model-id-in-openrouter-s-public-catalog-z-ai-glm-5-3`
Licence: event synthesis © changelogs.info, CC BY 4.0. Linked sources belong to their vendors.