Grok 4.20 Beta Reasoning
Grok 4.20 Beta Reasoning is xAI's reasoning model in the Grok 4.20 beta generation, supporting extended thinking for complex problem-solving with low hallucination rates and strict prompt adherence.
import { streamText } from 'ai'
const result = streamText({ model: 'xai/grok-4.20-reasoning-beta', prompt: 'Why is the sky blue?'})What To Consider When Choosing a Provider
Zero Data Retention
AI Gateway does not currently support Zero Data Retention for this model. See the documentation for models that support ZDR.Authentication
AI Gateway authenticates requests using an API key or OIDC token. You do not need to manage provider credentials directly.
Grok 4.20 Beta Reasoning is in beta. Expect potential changes before general availability.
Extended thinking adds tokens and latency to each response. For tasks that don't benefit from structured reasoning, the non-reasoning variant is faster and cheaper.
When to Use Grok 4.20 Beta Reasoning
Best For
Complex problem solving
Requiring multi-step reasoning and extended thinking
Mathematical and scientific analysis:
Structured chain-of-thought improves accuracy
Code debugging and review
That benefits from step-by-step logical analysis
High-stakes decisions:
Low hallucination rates and traceable reasoning are critical
Research and analysis tasks
Operating over large document collections within the context of 2M tokens
Consider Alternatives When
Speed-focused tasks:
The Grok 4.20 Non-Reasoning variant delivers faster responses at lower cost
Multi-agent orchestration:
The Grok 4.20 Multi-Agent variant is purpose-built for agent collaboration
Stable production deployments:
Beta models introduce risk. Use Grok 4.1 Fast Reasoning or the full Grok 4 instead
Simple direct-response tasks:
Reasoning overhead adds cost without improving quality
Conclusion
Grok 4.20 Beta Reasoning adds extended thinking to the Grok 4.20 beta generation. Use it for complex analysis, multi-step reasoning, and code debugging where deliberation depth improves accuracy. For production stability, prefer grok-4.20-reasoning.
FAQ
Grok 4.20 Beta Reasoning generates chain-of-thought reasoning traces before producing final answers. This extended thinking improves accuracy on complex tasks at the cost of additional latency and tokens.
2M tokens.
Yes. Grok 4.20 Beta Reasoning is currently in beta. Behavior, pricing, or availability may change before general availability.
Rates are listed on this page. They reflect the providers routing through AI Gateway and shift when providers update their pricing.
Use your Vercel AI Gateway API key with xai/grok-4.20-reasoning-beta as the model identifier. AI Gateway manages routing and authentication automatically.
Yes. Chain-of-thought traces are included in the API response. You can inspect and log them for debugging and auditing.
Zero Data Retention is not currently available for this model. ZDR on AI Gateway applies to direct gateway requests; BYOK flows aren't covered. See https://vercel.com/docs/ai-gateway/capabilities/zdr for details.
