Published on: September 29, 2025

2 min read

Greater AI choice in GitLab Duo: Claude Sonnet 4.5 arrives

Anthropic's newest model for coding and agentic workflows is now available in GitLab Duo Pro, Duo Enterprise, and Duo Agent Platform.

GitLab now offers Claude Sonnet 4.5, Anthropic’s most advanced model for coding and real-world agents, directly in the GitLab Duo model selector.

Users now have the flexibility to choose Claude Sonnet 4.5 alongside other leading models, enhancing their GitLab Duo experience with upgrades in tool orchestration, context editing, and domain-specific capabilities. With top performance on SWE-bench Verified (77.2%) and strengths in cybersecurity, finance, and research-heavy workflows, GitLab users can apply Claude Sonnet 4.5 to bring sharper insights and deeper context to their development work.

"Having Claude Sonnet 4.5 in GitLab is a big win for developers. It’s a really capable coding model, and, when you use it with the GitLab Duo Agent Platform, you get smarter help right in your workflows. It’s the kind of step that makes development easier," said Taylor McCaslin, Principal, Strategy and Operations for AI Partnerships at GitLab.

GitLab Duo Agent Platform + Claude Sonnet 4.5

GitLab Duo Agent Platform extends the value of Claude Sonnet 4.5 by orchestrating agents, connecting them to internal systems, and integrating them throughout the software lifecycle. This combination creates a uniquely GitLab experience — where advanced reasoning and problem-solving meet platform-wide context and security. The result is faster development, more accurate outcomes, and stronger organizational coverage, all delivered inside the GitLab workflow developers already use every day.

Where you can use Claude Sonnet 4.5

Claude Sonnet 4.5 is now available as a model option in GitLab Duo Agent Platform Agentic Chat on GitLab.com. You can choose Claude Sonnet 4.5 from the model selection dropdown to leverage its advanced coding capabilities for your development tasks.

Dropdown selection for Claude Sonnet 4.5 in GitLab Duo

Note: Ability to select Claude Sonnet 4.5 in supported IDEs will be available soon.

Get started

GitLab Duo Pro and Enterprise customers can access Claude Sonnet 4.5 today. Visit our documentation to learn more about GitLab Duo capabilities and models.

Questions or feedback? Share your experience with us through the GitLab community.

Want to try GitLab Ultimate with Duo Enterprise? Sign up for a free trial today.

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