Grok 4.3

Overview

Grok 4.3 is a frontier model from xAI with a 1-million-token context window, offering strong reasoning across long documents, multi-source datasets, and complex technical content. Released at the end of April 2026, it is available through OpenRouter and is designed for teams that need to process and reason over very large bodies of information in a single model call.

For software engineering teams, the 1M-token window is particularly useful for ingesting entire dependency graphs, large monorepo change histories, or comprehensive security audit outputs without chunking and retrieval overhead.

Key Capabilities

• 1M Token Context Window — process entire monorepo dependency manifests, audit reports, or release histories in one pass
• Frontier Reasoning — strong chain-of-thought reasoning for nuanced technical analysis
• Tool Use — function-calling support for integration with external APIs and developer toolchains
• Multi-Document Synthesis — reason across multiple documents simultaneously without retrieval latency
• Long-Horizon Planning — sustained coherence across very long context interactions

Use Cases for Engineering Teams

• Full-Dependency Graph Analysis — load complete dependency trees and reason about transitive conflicts and version drift
• Multi-Repository Audits — compare dependency configurations across many services in a single context
• Long-Document Technical Reasoning — process comprehensive security audit reports and extract prioritised action items
• Root Cause Analysis — correlate build failures across large log histories to identify dependency-related regressions
• Architecture Review — evaluate proposed dependency changes against established architecture constraints

Technical Specifications

• Context Window: 1,000,000 tokens
• Pricing: Not publicly announced at launch
• Open Weight: No
• Release Date: 2026-04-30

Provider

Grok 4.3 is developed by xAI. For the latest information, visit the OpenRouter listing.