Codex Security is an open-source execution harness and sandboxing framework developed by OpenAI. It is designed to provide secure, isolated execution environments specifically for running autonomous coding agents and untrusted model-generated code. In practice, Codex Security operates as an infrastructure layer combining container configurations with system-level security profiles and a TypeScript SDK (@openai/codex-security). Developers integrate the harness into agent workflows to constrain file system access, network interaction, and process execution when agents test, build, or iterate on code. What distinguishes Codex Security from standard CLI coding agents is its focus on isolation and containment. Rather than executing shell commands directly on the host machine, it provides Docker Compose configurations with AppArmor enforcement to prevent unauthorized privilege escalation, host contamination, or destructive agent behavior. Codex Security is distributed as open-source software under the Apache-2.0 license, making it available for local development setups, custom agent platforms, and CI/CD pipelines.
Tags: cli, code assistant, coding agent, developer tools, OpenSource