---
agentTools:
  projectIndex: https://docs.arthur.ai/llms.txt
---

# December 2025 Release Notes

## Arthur Platform

* Arthur is solving the agent visibility gap with the launch of the industry’s first Agentic Discovery & Governance (ADG) Platform. Arthur’s ADG platform was built to turn agent chaos into a structured, scalable operation.
  * [Learn more about building your company's ADG strategy.](https://arthur.ai/blog/adg?utm_source=docs\&utm_medium=release-notes\&utm_campaign=adg-launch)
* New agentic features are arriving in January 2026 that will provide powerful tools for testing, tracing, and deploying agent based workflows.
  * Interested in trying it first? Email <product@arthur.ai> to join the early access group.

## Arthur Evals Engine OSS

**New Features**

* Test & Preview Custom Metrics Before Saving: Users can now validate their custom metrics directly within the creation and editing workflow.
* Users can run the metric against available datasets to preview results and confirm the logic behaves as expected before saving.

**Bug Fixes**

* Sketch metrics can now be created and calculated without specifying any dimension columns.
  Frontend No Longer Overwrites User-Defined Metadata for Reported Metrics.

## Community

**Venture Backed Startup?**

* Join Arthur’s Start Up Partner Program: If you’re building a venture-backed startup that uses AI Agents and are trying to figure out how to reliably ship them to production, this program is perfect for you. [Apply Today](https://www.arthur.ai/startup-program?referrer=dec-product-release-notes)