A Historic Month for GitHub Copilot
December 2025 will go down in history as the month GitHub Copilot truly became multi-model. With the general availability arrival of GPT-5.2, Claude Opus 4.5, and Gemini 3 Pro, developers now have access to the best AI models from every provider, directly in their IDE.
New Models Available
GPT-5.2, GPT-5.1 and Codex Variants
December 17, 2025 — OpenAI massively deploys its GPT-5 family in GitHub Copilot:
| Model | Status | Specialization |
|---|---|---|
| GPT-5.2 | GA | Latest generation, improved capabilities |
| GPT-5.1 | GA | Balanced performance |
| GPT-5.1-Codex | GA | Optimized for code |
| GPT-5.1-Codex-Max | GA | Maximum capabilities for code |
Anthropic’s Claude Opus 4.5
December 18, 2025 — Anthropic’s flagship model goes into general availability after a preview period. Claude Opus 4.5 is renowned for its deep reasoning capabilities and exceptional contextual understanding.
December 3, 2025 — Expansion to IDEs: Claude Opus 4.5 becomes available in Visual Studio, JetBrains IDEs, Xcode, and Eclipse.
🔗 Claude Opus 4.5 GA Changelog
Google’s Gemini 3
| Model | Date | Status | Availability |
|---|---|---|---|
| Gemini 3 Flash | Dec 17 | Public Preview | VS Code |
| Gemini 3 Pro | Dec 12 | Available | VS, JetBrains, Xcode, Eclipse |
Gemini 3 Flash is now rolling out in public preview in GitHub Copilot. This model is ideal for tasks requiring speed and efficiency.
🇬🇧 Gemini 3 Flash is now rolling out in public preview in GitHub Copilot. This model is ideal for tasks requiring speed and efficiency. — @github on X
Agent Skills: The Era of Specialized Agents
December 18, 2025 — GitHub Copilot now supports Agent Skills, allowing agents to leverage specialized skills for complex tasks.
December 3, 2025 — Announcement of Custom Agents created by GitHub partners for observability, infrastructure as code, and security.
| Domain | Feature |
|---|---|
| Observability | Agents for monitoring and debugging |
| Infrastructure as Code | Terraform, CloudFormation, etc. |
| Security | Vulnerability analysis, compliance |
Copilot Memory: Early Access
December 19, 2025 — GitHub launches early access to Copilot Memory for Pro and Pro+ subscribers. This feature allows Copilot to remember context between sessions, offering a more personalized and continuous experience.
Auto Model Selection
December 10, 2025 — Automatic model selection goes into general availability in VS Code. Copilot intelligently chooses the best model depending on the task: speed with Gemini 3 Flash, reasoning with Claude Opus 4.5, or code generation with GPT-5.1-Codex.
December 8, 2025 — Pro and Pro+ subscribers can also manually choose their preferred model via the Model Picker for the coding agent.
🔗 Auto Model Selection Changelog
Improved GitHub MCP Server
December 10, 2025 — GitHub’s MCP (Model Context Protocol) server receives major improvements:
- Tool-specific configuration support
- Better integration with existing workflows
- Optimized performance
C++ Editing Tools
December 16, 2025 — C++ code editing tools arrive in public preview, with specialized features for this demanding language.
Extended Copilot Code Review
December 17, 2025 — The Copilot code review feature becomes accessible to organization members without a Copilot license. A significant democratization for teams.
December 18, 2025 — Preview code review features are now supported in GitHub Enterprise Cloud with data residency.
Copilot Spaces: Public Spaces
December 1, 2025 — Copilot Spaces introduces public spaces and code view support, facilitating collaboration on shared projects.
Metrics and Dashboards
December brings several improvements for usage tracking:
| Date | Feature |
|---|---|
| Dec 18 | PR activity metrics at Enterprise level (preview) |
| Dec 16 | Copilot usage tracking by organization |
| Dec 5 | Code generation metrics dashboard |
What This Means
December 2025 confirms GitHub Copilot’s multi-model strategy. Developers are no longer limited to a single AI provider: they can choose GPT-5 for raw power, Claude Opus 4.5 for reasoning, or Gemini 3 for speed.
The arrival of Agent Skills and Copilot Memory foreshadows a development assistant that understands your context and can delegate tasks to specialized agents. GitHub Copilot is evolving from a simple autocompletion tool to a complete development assistance platform.