DeepSeek Reasonix

DeepSeek Reasonix is an open source AI coding agent designed for long autonomous runs that stay reviewable. A single local engine sits behind four front ends: a full screen terminal interface, a desktop app for macOS, Windows and Linux, a local web UI started with reasonix serve, and editor integration for VS Code and VSCodium through an extension or any editor that speaks the Agent Client Protocol. Sessions, permissions, skills and MCP servers are shared across all four, so a task started in the terminal can be resumed in the desktop app. It is aimed at developers who want to leave an agent working on a repository for hours without losing oversight. Every tool call is gated, with reads, writes and shell commands approved separately, and a workspace sandbox limits what an approved command can touch. Plan mode holds every write until the plan has been read and approved, and each turn writes a checkpoint outside git, so any turn can be undone without touching commit history. The agent maps the codebase once per session, supports MCP over stdio, SSE and streamable HTTP, and runs Markdown skills and subagents for exploration, research, review and security review with isolated tool sets. Reasonix is free under the MIT licence. Users bring their own DeepSeek API key and pay DeepSeek directly for model usage; there is no Reasonix subscription. Two release lines exist: the stable 1.x desktop line, and a Studio 2.x preview with a new architecture. The CLI installs with npm or Homebrew and ships as a single Go binary with no runtime to install.