Grok 4.20 Multi-Agent vs GPT Image 1.5

xAI Grok 4.20 Multi-AgentOpenAI GPT Image 1.5
VendorxAIOpenAI
Context window2,048,000128,000
Max output1,000,000
ReasoningYesNo
Tool callingYesNo
File inputYesYes
Inputtext, imagetext, image
Outputtextimage
Released2026-03-082025-12-16