Custom rules in GitLab Duo Agentic Chat for greater developer efficiency

What this post added

This post introduces and details the implementation of custom rules for GitLab Duo Agentic Chat. It explains how to create these rules in `.gitlab/duo/chat-rules.md` to enforce specific development standards, including version control (e.g., Java 8, Python 3, multi-platform C++), style guides (e.g., C goto anti-patterns, VueJS patterns, Ansible linter compliance), and DevSecOps automation (CI/CD security scanning, documentation standards). It provides practical examples, guidelines for rule development, and links to demonstration projects and merge requests, enabling users to personalize AI assistant behavior.