Gemini 3.1 Pro at $2 / $12 per MTok is meaningfully cheaper than Claude Sonnet — and its context window dwarfs everything else on the market. For massive document analysis or "stuff a whole codebase into context" patterns, that capacity is real. Claude is more consistent on hard reasoning and noticeably more reliable in agentic loops, where Gemini's safety filters and occasional reasoning misses still cost you.
If your team lives in Workspace, Sheets, Docs, and Vertex, Gemini's integration is a feature you'll feel daily. Outside that orbit, Claude's API ergonomics and Sonnet's price-performance still win.