AI Research
Grok 4.6: xAI Ships a Long-Running Agent Model to OpenRouter
xAI announced Grok 4.6 on 12 August 2026, tuned for long-running agents and ambitious visual work. It is live on OpenRouter with a 500,000-token context at $2 per million input tokens, and the release date is confirmed by the official announcement.
AI-narrated summary, not a word-for-word reading.
Key takeaways
- check_circlexAI released Grok 4.6 on 12 August 2026, aimed at long-running agents, with reasoning on by default at high effort.
- check_circleOn OpenRouter it has a 500,000-token context and accepts text, images and files at $2 per million input and $6 per million output tokens.
- check_circleFine print: prompts over 200,000 tokens bill at $4 per million input and $12 per million output, and web search tool calls cost $5 each.
What Grok 4.6 changes
xAI announced Grok 4.6 on 12 August 2026. The model builds on Grok 4.5 with a particular focus on long-running agents and more ambitious interactive and visual work. The announcement says it stays with complex tasks across many steps, whether researching a topic, analysing information, working across a codebase, or turning an idea into a polished application.
On longer trajectories xAI reports more self-testing and verification, with the model checking its own work before moving on. It also produces stronger first passes on visual and interactive projects, which the announcement credits for faster iteration when starting from a concrete product idea.
Benchmarks
Grok 4.6 High posts an Artificial Analysis Intelligence Index score of 61, level with GPT-5.6 Sol Max, alongside 69.9% on CursorBench v3.2, 65.9% on DeepSWE v1.1, 1753 on GDPVal-AA v2 and 61.3% on FrontierCode v1.1 (Extended). Against Grok 4.5 High, the largest jumps are on agentic tasks: APEX-Agents moves from 47.1% to 57.5% and Terminal-Bench v3.0 from 15.7% to 26%.
Where it is available and what it costs
Grok 4.6 is live today in Cursor and Grok Build, with double included usage in both for the first week, plus the xAI API and partner platforms including OpenRouter, Vercel and Cloudflare. Pricing starts at $2 per million input tokens and $6 per million output tokens, with a fast variant at twice the price.
On OpenRouter the route is openrouter/x-ai/grok-4.6 with a 500,000-token context and text, image and file input. Reasoning is mandatory with high as the default effort, and xhigh, high, medium and low efforts are supported. Watch the fine print: OpenRouter bills prompts over 200,000 tokens at $4 per million input and $12 per million output, cached input reads at $0.50 per million, and web search tool calls at $5 each.
Detection in our index
AZ Labs endpoint monitoring first saw openrouter/x-ai/grok-4.6 at 15:45:17 UTC on 12 August. The OpenCode Zen route followed at 16:01:03 UTC, exactly 15 minutes and 46 seconds later.
Frequently asked questions
Is the Grok 4.6 release date confirmed?
Yes. xAI published the announcement on x.ai on 12 August 2026.
What does it cost on OpenRouter?
$2 per million input tokens and $6 per million output tokens. Prompts over 200,000 tokens bill at $4 per million input and $12 per million output, cached input reads at $0.50 per million, and web search tool calls cost $5 each.
Does it reason by default?
Yes. Reasoning is mandatory with high as the default effort. Xhigh, high, medium and low efforts are supported.
Where can I try it?
Cursor, Grok Build, the xAI API, and OpenRouter as openrouter/x-ai/grok-4.6. It is also on OpenCode Zen as grok-4.6.
Sources
Copyright & image credits
The article image is credited to © X.AI LLC. Source: xAI: Introducing Grok 4.6.