⚠ This model is no longer available

GLM-5.3-Prime was removed from RealRelay on 2026-10-23. This page is kept as a historical record: prices mentioned below are no longer valid, and the API no longer serves this model.

GLM-5.3-Prime

GLM-5.3-Prime is a high-speed variant from Z.ai with reasoning, tool calling and a 1M-token context window.

Similar models still available

Overview

GLM-5.3-Prime is a language model from Z.ai. It takes text as input and returns text as output, and it is published with support for reasoning and for tool calling.

Z.ai describes this entry as a high-speed variant that uses inference acceleration to deliver higher output throughput. On RealRelay the model is callable under the ID alibaba/glm-5.3-prime through an OpenAI-compatible endpoint.

The context window is 1M tokens, which is the full working space for a single request in this model.

Capabilities

GLM-5.3-Prime supports reasoning and tool calling. Tool calling lets an application expose its own functions to the model so that the model can ask for them during a request.

Input modality is text and output modality is text, so prompts and completions stay in plain text form.

The context window spans 1M tokens, and inference acceleration is what raises output throughput relative to a standard run of the same weights.

Pricing

GLM-5.3-Prime is metered per token. Input is no longer offered per 1M tokens and output is no longer offered per 1M tokens. Cached input reads are billed at no longer offered per 1M tokens.

Every rate above is quoted per 1M tokens, so a request is priced by the tokens it sends and the tokens it returns, with the 1M-token context window setting the upper bound on a single request.

Use cases

Reasoning work that needs a large working space fits the 1M-token context window, since a single request can carry an input of that size.

Applications that combine a reasoning step with calls into their own functions can use tool calling to route those calls.

Workloads that generate a lot of output text can take advantage of the higher output throughput that inference acceleration provides.

What is GLM-5.3-Prime?

GLM-5.3-Prime is a text model from Z.ai that supports reasoning and tool calling. It is published as a high-speed variant that uses inference acceleration for higher output throughput, and it offers a 1M-token context window.

How much does GLM-5.3-Prime cost?

Input is no longer offered per 1M tokens and output is no longer offered per 1M tokens. Cached input reads are billed at no longer offered per 1M tokens.

What is the context window of GLM-5.3-Prime?

The context window is 1M tokens.

What inputs and outputs does GLM-5.3-Prime handle?

It accepts text input and returns text output; both modalities are text only.

Does GLM-5.3-Prime support tool calling?

Yes. The model is published with tool calling and reasoning support, so it can ask an application to run its own functions during a request.

When was GLM-5.3-Prime released?

The release date is September 23, 2026.

How do I call GLM-5.3-Prime through the OpenAI-compatible API?

Send a chat request to RealRelay's OpenAI-compatible endpoint with the model ID alibaba/glm-5.3-prime, using your RealRelay API key.

Pricing

no longer offered
GLM-5.3-Prime was removed from RealRelay on 2026-10-23. This page is kept as a historical record: prices mentioned below are no longer valid, and the API no longer serves this model.

Specifications (as of 2026-10-23)

Context window
1M
Released
2026-09-23
Input
Text
Output
Text
Capabilities
Reasoning, Tool use

GLM-5.3-Prime API Pricing & Specs · This model is no longer available | RealRelay.ai