GLM-5.3-Flash
GLM-5.3-Flash is Z.ai's lower-cost multimodal model for coding, long-horizon agent workflows, and visual reasoning. It is the first natively multimodal model in the GLM-5 series, combining text, image, and video understanding with stronger coding and agent performance than earlier GLM flash-tier behavior would suggest. Z.ai positions it as a default model for frequent professional work that needs fast feedback, efficient long-context serving, and reliable reasoning across software, documents, charts, interfaces, screenshots, and other visually grounded tasks.
GLM-5.3-Flash is served through Runware's compatible endpoints, which take another provider's request format. Point the SDK you already use at Runware by changing the base URL and the API key, and set model to zai:glm@5.3-flash.
Requests and responses keep the provider's format, so its reference documents every parameter.
| Endpoint | Format |
|---|---|
/v1/chat/completions | OpenAI Chat Completions |
Chat Completions
curl -X POST https://api.runware.ai/v1/chat/completions \
-H "Authorization: Bearer $RUNWARE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "zai:glm@5.3-flash",
"messages": [{"role": "user", "content": "What is the capital of France?"}]
}'from openai import OpenAI
client = OpenAI(
api_key="your_runware_api_key",
base_url="https://api.runware.ai/v1",
)
response = client.chat.completions.create(
model="zai:glm@5.3-flash",
messages=[{"role": "user", "content": "What is the capital of France?"}],
)
print(response.choices[0].message.content)import OpenAI from 'openai';
const client = new OpenAI({
apiKey: 'your_runware_api_key',
baseURL: 'https://api.runware.ai/v1',
});
const response = await client.chat.completions.create({
model: 'zai:glm@5.3-flash',
messages: [{ role: 'user', content: 'What is the capital of France?' }],
});
console.log(response.choices[0].message.content);Compatible APIs covers streaming, tool calling and how the endpoint differs from OpenAI, and the OpenAI API reference lists every parameter.