The AI Wire ●

xAI launched Grok 4.6, an agent-focused post-training upgrade on the 4.5 base with a 500,000-token context window. It tied GPT-5.6 Sol on the Artificial Analysis intelligence index while priced at just $2/$6 per million tokens — far below rivals.

The release came after SpaceX acquired xAI in February 2026, with the combined company styling itself SpaceXAI. Grok 4.6 was its first major model launch under the new structure.

Grok 4.6's pitch was value: near-frontier intelligence at budget pricing, undercutting competitors who charged multiples more for similar benchmark scores.

xAI released Grok 4.6 on August 12, 2026, a post-training upgrade on the same V9 base as Grok 4.5 pitched as its frontier model for coding, agentic tool use and knowledge work. It keeps the 500,000-token context window, accepts text and image inputs with text-only output, and offers selectable reasoning effort (low, medium, high, xhigh).

Pricing is $2 input / $6 output per million tokens for prompts under 200k tokens, doubling to $4/$12 above that line, with a faster variant at a premium. Available in the xAI API, Cursor, Grok Build, GitHub Copilot, OpenRouter, Vercel, Cloudflare and Microsoft Foundry. xAI reports gains over Grok 4.5 across its benchmark table, with independent Artificial Analysis testing placing it second only to Claude Opus 5 on agentic knowledge work at much lower token cost. (Filed September 21 as backfill.)

xAI released Grok 4.1, which topped agentic benchmarks and sharply cut hallucinations — down to 4.22% from 12.09% on xAI's evaluations. The update also brought a warmer, more personable default personality.

Grok 4.1's hallucination reduction addressed one of the line's longest-standing weaknesses. xAI pitched it as the model that finally paired Grok's real-time X awareness with trustworthy answers.

The release kept xAI competitive through the intense November 2025 three-lab shootout, holding the line while rivals shipped their own flagships within days.

xAI released Grok-4, which Musk called 'the most intelligent model in the world,' with native tool use and stronger reasoning. Alongside it came Grok-4 Heavy, which runs multi-agent ensembles on hard problems, sold through a $300-per-month SuperGrok Heavy tier.

Grok-4 Heavy's ensemble approach — spawning multiple agents to work a problem in parallel — previewed the multi-agent patterns the whole industry adopted in 2026. The $300 tier was the priciest consumer AI subscription to date.

Grok-4 held xAI's frontier position through the second half of 2025, with the 4.1 refresh arriving in November.

xAI launched Grok-3, trained on its Colossus supercomputer with roughly ten times the compute of Grok-2. The release added 'Think' reasoning mode and DeepSearch, an agentic research tool that scours the web and X.

Musk called Grok-3 the smartest AI on Earth at launch, and early benchmarks put it at or near the frontier on math, science, and coding. The release event was streamed live with xAI engineers demoing the model.

Grok-3's compute-heavy approach validated xAI's bet on scaling infrastructure fast, and it became the base for the Grok-4 generation later in 2025.

xAI released Grok-2 in August 2024, its first frontier-class model, beating Claude 3.5 Sonnet on some benchmarks. It added image generation powered by Black Forest Labs' FLUX model, making Grok one of the first major chatbots to generate images natively.

The image generation launch was characteristically Musk: fewer content restrictions than rivals, which drew both users and criticism. Grok-2's benchmark gains showed xAI's Colossus training cluster paying off.

Grok-2 marked xAI's arrival as a genuine frontier lab rather than a fast follower, setting up the compute-heavy Grok-3 push in 2025.

xAI released Grok-1.5 with a 128,000-token context window and substantially stronger reasoning, closing the gap with frontier rivals. A vision variant, Grok-1.5V, added image understanding on April 12.

The release showed xAI could iterate quickly: five months after the Grok debut, the model was competitive on standard benchmarks. Musk promised Grok-1.5 would reach X Premium+ subscribers within days.

Grok-1.5 set up the bigger Grok-2 push later in 2024, when xAI aimed to move from catching up to leading.

xAI debuted Grok in November 2023, a chatbot for X Premium+ subscribers pitched as witty and rebellious, with real-time access to posts on X. It was Elon Musk's answer to ChatGPT, built by his new AI company barely four months after its founding.

Grok's X integration gave it a genuine differentiator: answers informed by live social media. In March 2024 xAI open-sourced Grok-1's weights, a surprise move that won goodwill with the open-source community.

The launch established xAI's playbook — move fast, differentiate on X data and personality, and iterate the Grok line aggressively.