Contextium

Contextium is an open-source methodology and toolkit designed to provide structure and continuity for AI agent workflows, particularly in coding and development contexts. It addresses the common problem of AI sessions starting from scratch and losing context or memory over time, leading to repetitive explanations and a lack of persistent rules. By introducing an operating system-like approach, Contextium enables each AI session to build upon the last, preserving both decisions and reasoning.

The tool organizes work into a loop of distinct phases: planning with a SPEC of success using the 'Think' verb, implementing from a clean context with 'Do', and journaling outcomes and reasoning with 'Wrap'. These phases are executed as commands, each with its own session and context. Additional commands include 'implement-audit' for adversarial review and 'explain' for deeper investigation, among others. Contextium enforces rules through mechanisms wired to hooks—such as a commit gate, a destructive-git guard, and a memory-write guard—ensuring that important practices are automatically enforced rather than merely advisory. The system maintains two layers of memory: the git log for tracking changes (what happened) and a daily journal for capturing the rationale behind decisions (why they happened), enabling users to reconstruct past choices and reasoning.

Contextium is delivered as a terminal-based tool that can be installed via a shell command. Upon installation, it prompts users to select which AI tools they use (including Claude Code, Gemini, Codex, Cursor, and Copilot), their name, and the desired level of AI autonomy. It then generates native configuration files for each selected tool, ensuring model-agnostic compatibility and zero lock-in. All data and context are stored as plain markdown files within a git repository owned by the user, preserving portability and user control. The toolkit includes templates for integrating with external services such as GitHub, Google, and Todoist, which can be configured as needed.

Contextium is released under the MIT License and is fully open source. Its design emphasizes portability, accountability, and a structured approach to managing AI agent sessions and memory in development workflows.