Grok 4.20 Multi-Agent vs gpt-5-nano

xAI Grok 4.20 Multi-AgentOpenAI gpt-5-nano
VendorxAIOpenAI
Context window2,048,000400,000
Max output1,000,000128,000
ReasoningYesYes
Tool callingYesYes
File inputYesYes
Inputtext, imagetext, image
Outputtexttext
Released2026-03-082025-08-07