Grok 4.20 Beta Is Now Available in Puter.js

Puter.js now supports Grok 4.20 Beta and Grok 4.20 Multi-Agent Beta, xAI's newest flagship models featuring a native multi-agent collaboration system.

What is Grok 4.20 Beta?

Grok 4.20 Beta is xAI's latest flagship model, introducing a native 4-agent collaboration system where four specialized agents—Grok, Harper, Benjamin, and Lucas—reason in parallel and debate internally before delivering a unified response. Built on a ~3T parameter Mixture-of-Experts backbone with up to 2M token context, it claims a 65% reduction in hallucinations over Grok 4.1 with strong gains in coding, math, and engineering reasoning.

The model deploys four specialized agents that think in parallel and cross-verify each other's outputs before presenting a unified answer:

• Grok (Coordinator) — decomposes queries into sub-tasks, assigns them to other agents, resolves conflicts, and delivers the final synthesis
• Harper (Researcher) — searches the web and X, pulls documents, and assembles evidence in real time
• Benjamin (Verifier) — handles rigorous step-by-step reasoning, numerical computation, and code execution
• Lucas (Creative) — approaches problems from unconventional angles with alternative framings and innovative solutions

Key highlights:

• 65% Fewer Hallucinations — hallucination rate dropped from ~12% to ~4.2%, scoring best on the AA-Omniscience hallucination benchmark
• Rapid-Learning Architecture — improves weekly from real-world feedback, a different deployment philosophy than competitors' static releases
• ~3T Parameter MoE Backbone — ~500B parameters active per query for efficient inference at massive scale
• 2M Token Context — process extensive codebases, documents, and datasets in a single prompt

Grok 4.20 Multi-Agent Beta

The Multi-Agent Beta variant is optimized for orchestrating multiple agents that collaborate on deep research tasks. It supports web search and X search tools natively and is designed for developer workflows requiring structured multi-agent collaboration.

Examples

Text generation

puter.ai.chat("Explain how transformer architectures work",
  { model: 'x-ai/grok-4.20-beta' }
);

Streaming

const response = await puter.ai.chat(
  "Compare microservices vs monolithic architecture for a startup",
  { model: 'x-ai/grok-4.20-beta', stream: true }
);

for await (const part of response) {
  puter.print(part?.text);
}

Multi-turn conversation

const messages = [
  { role: "user", content: "What are the trade-offs of using Rust for web backends?" },
];

const response = await puter.ai.chat(messages, { model: 'x-ai/grok-4.20-beta' });

messages.push(response.message);
messages.push({ role: "user", content: "How does it compare to Go for the same use case?" });

const followUp = await puter.ai.chat(messages, { model: 'x-ai/grok-4.20-beta' });

Get Started Now

Just add one library to your project:

// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';

Or add one script tag to your HTML:

<script src="https://js.puter.com/v2/"></script>

No API keys and no infrastructure setup. Start building with Grok 4.20 Beta immediately.

Learn more:

• Free, Unlimited Grok API
• Puter.js AI Documentation