Gemini 4 Carbon Now Generally Available: Paid Gemini API Developers and Ultra Subscribers Get Access Today at an Introductory $2 / $10 per Million Tokens, as Antigravity Previews Multi-Agent /swarm

Core Background and Industry Pain Points

When Google announced Gemini 4 Carbon on October 28, it went only to a set of cybersecurity defenders in the Fairwind Program, so developers and regular users could not use it. For teams that want a frontier model for long-running agent work, a model they can read about but not call is the main problem. On November 10, Google opened Carbon broadly, and Sundar Pichai, Logan Kilpatrick, and Josh Woodward confirmed the rollout on X.

Architecture Highlights and Underlying Mechanisms

Google positions Carbon one step above Argon. Argon remains the right choice for most coding and knowledge work, while Carbon spends more tokens to explore, reason deeply, and run longer self-verification loops, which suits multi-step coding and debugging and open-ended research. Alongside Carbon, Antigravity is previewing /swarm, which turns one prompt into a team of agents you can track in real time. Carbon can take roles such as architectural design, coordination, and auditing, while faster, lighter models work in parallel isolated workspaces and adversarial verifier agents test every change.

Authoritative Benchmarks and Measured Comparisons

These figures are cited in Google's blog. Carbon ranks #1 on CursorBench 4.0, Perplexity's WANDR, and Zapier's AutomationBench, at more than 2x lower cost per task than the next best external model. On the Multimodal Knowledge Agent (MKA) benchmark launched with Artificial Analysis, it ranks #2 at more than 6x lower average cost per task than the leader. On safety, it blocked 99% of attack trajectories in simulated cyberattack environments, cutting the per-attempt breach rate from 3.1% on Argon to 0.8%. Gray Swan measured a 2.17% automated cyberattack query success rate (9.86% for Argon), and Carbon passed 92% of a 375-task agentic honesty benchmark (70% for Argon). Google researchers also used Carbon with a new framework, AlphaProof Code, to generate millions of lines of Lean proof code and prove key security properties of the actual code behind Signal's cryptographic protocol in weeks.

Developer Adoption and Getting Started

Paying developers can call Carbon now through the Gemini API in Google AI Studio or Android Studio, and enterprises can pick it in Gemini for business through the API or the model drop-down. Ultra subscribers can use it directly in the Gemini app, AI Mode in Search, and Antigravity. The introductory price is $2 / $10 per million input / output tokens and becomes $4 / $20 after November 30, so teams planning heavy long-running workloads should finish their evaluation before the end of the month. Following Google's own guidance, keep Argon for everyday tasks, send the hardest debugging and architecture reviews to Carbon, and try /swarm in Antigravity to split work across agents. The rankings are cited by Google, so retest cost and quality on your own tasks before switching.