Text model

GLM-5.3 Flashx

z-ai/glm-5.3-flashx

z-ai/glm-5.3-flashx is a language model from Z.ai you can call on the OceanToken API, with a 1.05M-token context window and up to 131K output tokens; it supports reasoning, tool calling, image input, video input.

Price card, similar models and questions answered: GLM-5.3 Flashx on oceantoken.ai.

At a glance

API

POST /v1/chat/completions (also /v1/responses and /v1/messages). Base URL https://api.oceantoken.ai, your OceanToken key as the bearer token. The OpenAI SDKs work unchanged; see the Quickstart.

Download this spec (JSON) · llms.txt for AI assistants

Basic

curl https://api.oceantoken.ai/v1/chat/completions \
  -H "Authorization: Bearer $OCEANTOKEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "z-ai/glm-5.3-flashx",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
}'

import os
from openai import OpenAI

client = OpenAI(base_url="https://api.oceantoken.ai/v1", api_key=os.environ["OCEANTOKEN_API_KEY"])
response = client.chat.completions.create(
    model="z-ai/glm-5.3-flashx",
    messages=[
        {
            "role": "user",
            "content": "Write a haiku about the ocean.",
        },
    ],
)
print(response.choices[0].message.content)

import OpenAI from 'openai';

const client = new OpenAI({baseURL: 'https://api.oceantoken.ai/v1', apiKey: process.env.OCEANTOKEN_API_KEY});
const response = await client.chat.completions.create({
  "model": "z-ai/glm-5.3-flashx",
  "messages": [
    {
      "role": "user",
      "content": "Write a haiku about the ocean."
    }
  ]
});
console.log(response.choices[0].message.content);

Video input

curl https://api.oceantoken.ai/v1/chat/completions \
  -H "Authorization: Bearer $OCEANTOKEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
  "model": "z-ai/glm-5.3-flashx",
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "text",
          "text": "What happens in this video?"
        },
        {
          "type": "video_url",
          "video_url": {
            "url": "https://example.com/clip.mp4"
          }
        }
      ]
    }
  ]
}'

import os
from openai import OpenAI

client = OpenAI(base_url="https://api.oceantoken.ai/v1", api_key=os.environ["OCEANTOKEN_API_KEY"])
response = client.chat.completions.create(
    model="z-ai/glm-5.3-flashx",
    messages=[
        {
            "role": "user",
            "content": [
                {"type": "text", "text": "What happens in this video?"},
                {
                    "type": "video_url",
                    "video_url": {"url": "https://example.com/clip.mp4"},
                },
            ],
        },
    ],
)
print(response.choices[0].message.content)

import OpenAI from 'openai';

const client = new OpenAI({baseURL: 'https://api.oceantoken.ai/v1', apiKey: process.env.OCEANTOKEN_API_KEY});
const response = await client.chat.completions.create({
  "model": "z-ai/glm-5.3-flashx",
  "messages": [
    {
      "role": "user",
      "content": [
        {
          "type": "text",
          "text": "What happens in this video?"
        },
        {
          "type": "video_url",
          "video_url": {
            "url": "https://example.com/clip.mp4"
          }
        }
      ]
    }
  ]
});
console.log(response.choices[0].message.content);

Request parameters

Only what this model takes. Anything else in the request is left out before it reaches the model.

Message content

Besides a plain string, a message's content can be a list of parts:

image_url

An image, as a public https:// URL or a data URL.

{
  "type": "image_url",
  "image_url": {
    "url": "https://example.com/photo.jpg"
  }
}

video_url

A video, as a public https:// URL (a YouTube link works on models that take one) or a data URL.

{
  "type": "video_url",
  "video_url": {
    "url": "https://example.com/clip.mp4"
  }
}

Response

With stream: true, chat.completion.chunk events carry choices[].delta; the stream ends with data: [DONE].

{
  "id": "chatcmpl-...",
  "object": "chat.completion",
  "created": 1792000000,
  "model": "z-ai/glm-5.3-flashx",
  "choices": [
    {
      "index": 0,
      "message": {
        "role": "assistant",
        "content": "...",
        "reasoning_content": null,
        "tool_calls": null
      },
      "finish_reason": "stop"
    }
  ],
  "usage": {
    "prompt_tokens": 12,
    "completion_tokens": 20,
    "total_tokens": 32,
    "prompt_tokens_details": {
      "cached_tokens": 0
    },
    "completion_tokens_details": {
      "reasoning_tokens": 0
    }
  }
}

More examples and how errors and billing work: Text generation.

Compared with similar models

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The facts on this page were read from the live OceanToken catalog on 2026-11-05 (UTC), when the documentation was built. Prices are published on oceantoken.ai.