Worried about opaque AI agents silently breaking builds? Here’s what happened, why it matters, and what to do next: on 2025-11-18 Google unveiled Antigravity (public preview), an agent-first coding environment layered on Gemini 3 Pro (Windows/macOS/Linux) that also supports Claude Sonnet 4.5 and GPT-OSS; it embeds agents in IDEs/terminals with Editor and Manager views, persistent memory, human feedback, and verifiable Artifacts (task lists, plans, screenshots, browser recordings). Gemini 3 Pro previews in November 2025 showed 200,000- and 1,000,000-token context windows, enabling long-form and multimodal workflows. This shifts developer productivity, trust, and platform architecture—and raises risks (overreliance, complexity, cost, privacy). Immediate actions: invest in prompt design, agent orchestration, observability/artifact storage, and monitor regional availability, benchmark comparisons, and pricing.