# Version Overview
Multiple versions of a service can be added to an existing service, called service versions. The Version Overview presents all of the service versions for the selected service. The significance of how multiple versions can be called used is described in [Manage service versions and effective dates](/build-spark-services/manage-versions-and-effective-dates.md).
To access this feature, after choosing a specific service from [Folder overview](/navigation/folder-overview.md), choose the  "Version Overview" icon from the service sidebar.
## Review the history of versions
The *History* tab shows a list of all the service versions for a service.
* The service versions are shown in descending order.
* The "three-dot menu" also includes additional actions that can be taken on a service version.
### Download version overview
Spark will return an Excel file with a full list of all the service versions on this service. This also includes additional information such as any tags, [Neuron](/build-spark-services/neuron.md) versions used for compilation, filename and file sizes.
### View service version details
The [Service Documentation](/navigation/service-documentation.md) only includes the information from the latest version of a Spark service. To view the service documentation for older service versions, click the "three-dot" menu and choose *View service version details*.
### Analyze service version with AI
This opens a new window with an Excel worksheet viewer and chat window. You can ask questions about the workbook and understand more about the formulas and help to debug any issues. Multiple windows can also be invoked across services or service versions. This enables automated ability to compare between 2 different files.
See [Analyze service with AI](/build-spark-services/analyze-service-with-ai.md) for more information.
### Go to API Tester
Open the selected service version the [API Tester](/navigation/api-tester.md).
### Go to API Call History
Filter the [API Call History](/navigation/api-call-history.md) for the selected service version.
### Restore a previous version of a service as the latest version
An older version of a Spark service to be set as the latest service version. The *Release note* will be populated to indicate which service version this was restored from.
Click the "three-dot menu" and choose *Restore Version*.
### **Download service version**
Select different ways that you want to download the Excel file corresponding to the Spark service. You can also download the compiled [Neuron](/build-spark-services/neuron.md) file from this menu.
#### Remove Custom XML
{% hint style="info" %}
Removing Custom XML is simplified with the [Coherent Assistant](https://docs.coherent.global/assistant/) Debugger.
{% endhint %}
Spark may have injected Custom XML into an Excel workbook. You can remove this by following these steps:
1. In Excel for Windows, click the File menu.\
2. Then select *Info*, *Check for Issues*, *Inspect Document*. This option may be disabled if there are protections that are enabled on the workbook or any worksheets.\
3. In the following modal:
1. Check *Custom XML Data*.
2. It is recommended to uncheck *Hidden Rows and Columns* as this option is unstable.
4. If any Custom XML is found, the *Document Inspector* will report *Custom XML data was found.*
5. Click **Remove All** to remove all the Custom XML embedded in the Excel file.
### Make deployment request
Initiate a [Options](/navigation/options.md#deployment-request).
### Delete service version
Clean up extra unneeded service versions with this option. Note that all data relating to a particular service version will no longer be accessible including: the Excel file, associated API Call History entries, and testbed results run against the particular service version.
### Recompile service version
This can be used to recompile the Spark service using a particular version of Neuron. This is beneficial to take advantage of changes in the newer versions of the compiler or to use older versions for compatibility and testing purposes. More details can be found in [Manage tenant settings](/tenant-administration/manage-tenant-settings.md#choose-the-neuron-compiler-version-for-additional-service-versions).
## Visualize versions on a timeline
The *Timeline* tab presents a visual view of the service versions over time.
* The service versions are shown in descending order.
* The version that would be selected for the current date and time is highlighted in dark purple. See [Manage service versions and effective dates](/build-spark-services/manage-versions-and-effective-dates.md) for more information.
## Compare service versions
To understand differences between service versions, select any two versions using the checkboxes in the *Compare* column, and then click the **Compare versions** button. A pop-up screen will appear to display the progress of the model comparison process. The report will be automatically downloaded when complete.
The comparison report in the Excel workbook format includes a summary sheet that tallies the updated content across different categories from the older version of the model to the newer one. This sheet also provides an overview of the changes made for all the named cell ranges. Additionally, the report attaches the worksheets of the newer model and highlights any modifications using different colors.
---
# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://docs.coherent.global/navigation/version-overview.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.