Customize GitLab Duo Agent Platform

You can customize the Agent Platform to match your workflow, coding standards, or project requirements.

Customization options

Method	AI feature	Use cases
Use custom rules to provide instructions.	- GitLab Duo Chat - Agents - Flows	- Apply personal preferences. - Enforce team standards.
Create an AGENTS.md file to provide instructions.	- GitLab Duo Chat - Flows - Other non-GitLab AI coding tools	- Account for project-specific context. - Organize a monorepo. - Enforce directory-specific conventions.
Create MR review instructions to ensure consistent and specific code review standards in your project.	- Code Review Flow	Apply: - Language-specific review rules. - Security standards. - Code quality requirements. - File-specific guidelines.

Best practices

When you customize the Agent Platform, apply the following best practices:

Start with minimal, clear, and simple instructions, and add more as needed. Keep the instruction file as short as possible.
Make sure the instructions are specific and actionable. Provide examples as needed.
Choose the method that matches your use case.
Combine multiple methods to tailor and control how GitLab Duo behaves.

If you use multiple methods, consider the following file structure for your project:

Project root directory
|─ AGENTS.md                         # Applies to multiple Duo features
|─ .gitlab/duo/
   |─ chat-rules.md                  # Custom Chat-specific rules
   |─ mr-review-instructions.yaml    # Custom code review standards
   |─ ...                            # Other configuration as needed

You can include other configuration files in the .gitlab/duo/ folder, such as custom flow definitions, or an MCP server configuration file.

Document your choices in comments to explain why certain instructions exist.
Protect customization files with Code Owners to manage changes.