# December 9, 2025

Here are the most relevant improvements we've made since the last release:

## 📊 Dataset Improvements

We've enhanced dataset functionality with several key improvements:

* **Edit Dataset Items** - You can now edit dataset items directly from the UI, making it easier to update and refine your evaluation data.

* **Remove Dataset Upload Limit for Self-Hosted** - Self-hosted deployments no longer have dataset upload limits, giving you more flexibility for large-scale evaluations.

* **Dataset Item Tagging Support** - Added comprehensive tagging support for dataset items, enabling better organization and filtering of your evaluation data.

* **Dataset Filtering Capabilities by Any Column** - Filter datasets by any column in both the playground and dataset view, giving you flexible ways to find and work with specific data subsets.

* **Ability to Rename Datasets** - Rename datasets directly from the UI, making it easier to organize and manage your evaluation datasets.

## 📈 Experiment Updates

We've made significant improvements to experiment management and analysis:

* **Experiment-Level Metrics** - Compute experiment-level metrics (as opposed to experiment-item-level metrics) for better insights into your evaluation results. Read more in the [experiment-level metrics documentation](https://www.comet.com/docs/opik/evaluation/evaluate_your_llm#computing-experiment-level-metrics).

* **Rename Experiments & Metadata** - Update experiment names and metadata config directly from the dashboard, giving you more control over experiment organization.

* **Token & Cost Columns** - Token usage and cost are now surfaced in the experiment items table for easy scanning and cost visibility.

<Frame>
  <img src="https://files.buildwithfern.com/https://opik.docs.buildwithfern.com/docs/opik/2026-01-30T17:33:07.444Z/img/changelog/2025-12-09/experiment_updates.png" alt="Experiments page showing experiment-level metrics, graphs, and experiment items table with token and cost columns" />
</Frame>

## 🎮 Playground Improvements

We've made the Playground more powerful and easier to use for non-technical users:

* **Easy Navigation from Playground to Dataset and Metrics** - Quick navigation links from the playground to related datasets and metrics, streamlining your workflow.

* **Advanced filtering for Playground Datasets** - Filter playground datasets by tags and any other columns, making it easier to find and work with specific dataset items.

* **Pagination for the Playground** - Added pagination support to handle large datasets more efficiently in the playground.

* **Added Experiment Progress Bar in the Playground** - Visual progress indicators for running experiments, giving you real-time feedback on experiment status.

* **Added Model-Specific Throttling and Concurrency Configs in the Playground** - Configure throttling and concurrency settings per model in the playground, giving you fine-grained control over resource usage.

## 🚨 Enhanced Alerts

We've expanded alert capabilities with threshold support:

* **Added Threshold Support for Trace and Thread Feedback Scores** - Configure thresholds for feedback scores on traces and threads, enabling more precise alerting based on quality metrics.

* **Added Threshold to Trace Error Alerts** - Set thresholds for trace error alerts to get notified only when error rates exceed your configured limits.

* **Trigger Experiment Created Alert from the Playground** - Receive alerts when experiments are created directly from the playground.

## 🤖 Opik Optimizer Updates

Significant enhancements to the Opik Optimizer:

* **Cost and Latency Optimization Support** - Added support for optimizing both cost and latency metrics simultaneously. Read more in the [optimization metrics documentation](/docs/opik/agent_optimization/optimization/define_metrics#include-cost-and-duration-metrics).

* **Training and Validation Dataset Support** - Introduced support for training and validation dataset splits, enabling better optimization workflows. Learn more in the [dataset documentation](/docs/opik/agent_optimization/optimization/define_datasets#trainvalidation-splits).

* **Example Scripts for Microsoft Agents and CrewAI** - New example scripts demonstrating how to use Opik Optimizer with popular LLM frameworks. Check out the [example scripts](https://github.com/comet-ml/opik/tree/main/sdks/opik_optimizer/scripts/llm_frameworks).

* **UI Enhancements and Optimizer Improvements** - Several UI enhancements and various improvements to Few Shot, MetaPrompt, and GEPA optimizers for better usability and performance.

## 🎨 User Experience Enhancements

Improved usability across the platform:

* **Added `has_tool_spans` Field to Show Tool Calls in Thread View** - Tool calls are now visible in thread views, providing better visibility into agent tool usage.

* **Added Export Capability (JSON/CSV) Directly from Trace, Thread, and Span Detail Views** - Export data directly from detail views in JSON or CSV format, making it easier to analyze and share your observability data.

## 🤖 New Models!

Expanded model support:

* **Added Support for Gemini 3 Pro, GPT 5.1, OpenRouter Models** - Added support for the latest model versions including Gemini 3 Pro, GPT 5.1, and OpenRouter models, giving you access to the newest AI capabilities.

***

And much more! 👉 [See full commit log on GitHub](https://github.com/comet-ml/opik/compare/1.9.17...1.9.40)

*Releases*: `1.9.18`, `1.9.19`, `1.9.20`, `1.9.21`, `1.9.22`, `1.9.23`, `1.9.25`, `1.9.26`, `1.9.27`, `1.9.28`, `1.9.29`, `1.9.31`, `1.9.32`, `1.9.33`, `1.9.34`, `1.9.35`, `1.9.36`, `1.9.37`, `1.9.38`, `1.9.39`, `1.9.40`