GitHub repo JuliusBrussee/caveman — a TypeScript Claude Code / Codex / Gemini / Cursor skill that asks the agent to talk like a caveman. 74,940 stars and 4,230 forks as of 2026-06-20, MIT, 15 releases (latest v1.9.0 on 2026-06-12). Project-published benchmark of 10 real Claude API prompts shows 65% average output-token reduction (range 22–87%); caveman-compress sub-skill cuts 46% of tokens from real memory files. The README's own Important box is the lead caveat: caveman only affects output tokens — thinking/reasoning tokens are untouched.
On May 19, 2026, Google announced Gemini Spark, a 24/7 personal AI agent on Gemini 3.5 and the Antigravity harness, deeply integrated with Workspace (Gmail, Docs, Slides) and connected to Canva, OpenTable, and Instacart via MCP. Rollout: trusted testers in the week of May 19, then U.S. Google AI Ultra Beta; macOS app and roadmap features (texting, custom sub-agents, local browser) ship 'later this summer'.
A randomized controlled trial with 1,763 students and 12 schools in Sierra Leone shows Gemini's Guided Learning mode delivers 1.2-1.7 years of learning in eight weeks. But it's a single trial, in a single country, and the achievement gap widens.