# GLM-5.3

Complex coding and long-horizon agentic work. Z.ai's GLM-5.3 open-weights reasoning model for complex coding and long-horizon tasks. Served on GraphN managed inference behind an OpenAI-compatible API as `glm-5.3`.

## Overview

GLM-5.3 is Z.ai's open-weights reasoning model, aimed at complex coding and long-horizon tasks. It shares its base model with GLM-5.2, and Z.ai attributes every change to post-training. It reasons before answering, and this deployment returns the reasoning and any tool calls in their own response fields.

## Strengths

- Built for complex coding and long-horizon tasks
- Tool calling alongside separately returned reasoning
- 250K-token context window

## Use cases

- Coding agents with many tool calls per task
- Long multi-step tasks that must stay on track

## Good to know

Text input only on this alias.

## Specifications

- **Type**: Chat
- **Context**: 250K context
- **Parameters**: 753B total
- **License**: GLM-5.3 License
- **Family**: GLM-5
- **Weights**: zai-org/GLM-5.3
- **Pricing**: Input $1.40/1M · Output $4.40/1M

## API access

### curl

```bash
curl https://gateway.graphn.ai/v1/chat/completions \
  -H "Authorization: Bearer $GRAPHN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "glm-5.3",
    "messages": [{"role": "user", "content": "Hello"}]
  }'
```

### CLI

```bash
graphn model chat glm-5.3 -m "What is GraphN?"
```

### Python

```python
@function
async def ask(question: str) -> str:
    return await chat.complete(question, model="glm-5.3")
```

[Start free](https://graphn.ai/signup?next=%2Finference%2Fglm-5.3)

[Model card](https://huggingface.co/zai-org/GLM-5.3) · [Managed inference](https://graphn.ai/inference) · [Pricing](https://graphn.ai/pricing) · [API reference](https://graphn.ai/api)