xAI Launches Grok 4.3 on API: Tops Agentic Tool Calling Benchmarks

Grok 4.3 Now Available on xAI API

xAI has officially released Grok 4.3 on its API, positioning it as the company's fastest and most intelligent model to date. The launch targets developers building agentic AI applications that require strong instruction-following and tool use capabilities.

Benchmark Performance

According to xAI, Grok 4.3 tops the ArtificialAnalysis leaderboards in both agentic tool calling and instruction following. In enterprise domain evaluations by Vals AI, the model ranks #1 in case law and corporate finance — domains that demand precision and domain-specific accuracy.

Specifications

Context window: 1 million tokens

Pricing: $1.25/M input tokens, $2.50/M output tokens

Competitive Landscape

The Grok 4.3 release arrives at a time of intense competition in the agentic AI space, directly competing with OpenAI and Anthropic's latest models. Its 1M token context window makes it well-suited for processing long documents and handling complex multi-step enterprise workflows.