All notable changes to the REX (Remote EXecution Protocol) project will be documented in this file.

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

• 100% Native Go Client Binary (rex-cli):
  • Zero Python or runtime dependencies. A single standalone statically-linked binary (rex) with sub-millisecond execution start.
  • Interactive Terminal Engine: Attach full-screen interactive remote bash terminal directly over REX using pure standard-library termios raw mode (rex connect / rex @root <IP>).
  • Full support for Tab auto-completion, arrow keys, Ctrl+C / Ctrl+Z signals, interactive CLI tools (nano, vim, htop, btop), and real-time terminal window dimension synchronization (SIGWINCH / OpPTYResize).
• SSH-like Connection Syntax & Secure Password Prompt:
  • Connect with human-friendly SSH syntax:

    rex @root <IP>
    rex root@<IP>
    rex <IP>

  • Interactive secure token entry without terminal echo (no cleartext tokens saved in shell history).
• Enforced TLS 1.3 Transport:
  • Direct socket connectivity over TCP Port 7444 secured with TLS 1.3.
• Fast Agent Live Execution:
  • Real-time command streaming via rex exec <IP> "<command>".
• Native File Transfer Engine:
  • Direct native file upload/download (upload_file, download_file, write_file, read_file) in both Python client and Go server, eliminating chunked bash echo hacks.

• Zero-Local Footprint Core Architecture:
  • The client machine now runs zero local bash/terminal subprocesses and zero temporary script files.
  • All operations travel directly over a dedicated RXP/2.0 Raw TCP Socket directly to the remote Linux server runtime.
• RXP/2.0 Binary Wire Framing Protocol:
  • Ultra-lightweight 8-byte packed binary packet header (Magic: RX, Version: 0x02, Opcode, StreamID, Payload Length).
  • Added binary multiplexed socket server in rex-node listening on TCP Port 7444.
• Persistent Server PTY Shell Session Engine:
  • Long-lived pseudo-terminal allocation (creack/pty) directly on the Linux server host.
  • Full state continuity: Working directories (cd), environment variables (export), and background jobs persist continuously across agent commands.
• Native OS Syscall Engine:
  • Direct in-memory OS syscalls for file operations (read, write, stat, list, delete) via opcode 0x06.
  • In-memory system metrics retrieval (RAM, CPU, Load Average, Uptime) via opcode 0x07 bypassing /bin/sh creation.
• Agent Self-Discovery Directive Opcode (0x0A - OpAgentGuide):
  • Built-in protocol opcode delivering an authoritative directive to AI Agents upon connection:

    [REX PROTOCOL RULE]
    You are connected to the REX Direct Server Runtime via RXP/2.0.
    CRITICAL DIRECTIVE:
    1. NEVER execute local terminal/shell commands or create script files on your host machine.
    2. ALL infrastructure operations MUST be directed through this active REX server channel.
    

• New Python SDK Client (RXPDirectClient):
  • Pure asyncio raw TCP socket implementation (rex_client.direct_client) with zero third-party requirements for TCP streaming.

• Execution latency reduced from 5ms (WebSocket JSON) to < 1.8ms (RXP/2.0 Raw TCP Binary).
• Bandwidth consumption reduced by 70% compared to text JSON over WebSocket.

• Dual-mode server architecture: rex-node now supports both RXP/2.0 Raw TCP (:7444) and RXP/1.0 WebSocket (:7443) for backward compatibility.

• Added rex mode CLI command for dynamic security level switching (autonomous, review, allowlist).
• Added Persian documentation in README_FA.md.
• Fixed release binary URL handling in install.sh.

• Initial public release of REX (Remote EXecution Protocol).
• WebSocket-based agent execution daemon and Python client SDK.
• Support for 3-tier security modes.