TeamCity 2020.1 Help

Typed Parameters

When adding a build parameter (system property, environment variable or configuration parameter), you can extend its definition with a specification that will regulate the parameter's control presentation and validation. This specification is the parameter's meta-information that is used to display the parameter in the Triggering a Custom Build dialog. It allows making a custom build run more user-friendly and usable by non-developers.

Consider a simple example. You have a build configuration in which you have a hard-to-read build parameter that regulates if a build has to include a license or not. The parameter can be either true or false, and is false by default. It may be clear for a build engineer, which build parameter regulates license generation and which value it is to have, but it may not be obvious to a regular user.

Using the build parameter's specification you can make your parameters more readable in the Run Custom Build dialog.

Adding Parameter Specification

To add specification to a build parameter, click the Edit button in the Spec area when editing/adding a build parameter.

All parameters specifications support a number of common properties, such as:

  • Label: some text that is shown near the control in the Run Custom Build dialog.

  • Description: some text that is shown below the control containing an explanatory note of the control use.

  • Display:
    • if hidden is selected, the parameter will not be shown in the Run Custom Build dialog, but will be sent to a build;

    • if prompt is selected, TeamCity will always require a review of the parameter value when clicking the Run button (won't require the parameter if build is triggered automatically);

    • if normal is selected, the parameter will be shown as usual.

  • Read-only: if the box is checked, it will be impossible to override the parameter with a different value.

  • Type:
    • a simple text field with the ability to validate its value using regular expression;

    • a checkbox;

    • a select control;

    • a password field.

The table below provides more details on each control type.




The default option. Represents a usual text string without any extra handling


True/false option represented by a checkbox


"Select one" or "select many" control to set the value to one of predefined settings.


This is designed to store passwords or other secure data in TeamCity settings. TeamCity makes the value of the password parameter never appear in the TeamCity web UI: it affects the settings' screens and the Run Custom Build dialog where password fields appear. Also, the value is replaced in the build's Parameters tab and build log.

The password value is stored in the configuration files under TeamCity Data Directory. Depending on the server Encryption Settings, the value is either scrambled or encrypted with a custom key.

The build log value is hidden with a simple search-and-replace algorithm, so if you have a trivial password of "123", all occurrences of "123" will be replaced, potentially exposing the password. Setting the parameter to the password type does not guarantee that the raw value cannot be retrieved. Any project administrator can retrieve it, and any developer who can change the build script could potentially write malicious code to get the password.

Note that if you switch an existing parameter from the password type to any other type, the original password value will be lost.

Depending on the specification's type, there are additional settings.


Allowed value- choose the allowed value. For the Regex option, specify Pattern, a Java-style regular expression to validate the field value, as well as a validation message.


Checked value/ Unchecked value: Specify values for the parameter to have depending on the checkbox's state.

It is recommended to specify the checked value and keep the default value and the unchecked value of the parameter the same.

Depending on the way the build is triggered, the checkbox behavior will be as follows:

  • if the build is triggered by an automatic trigger or by clicking the Run button (without the run custom build dialog), the default value is used

  • if the build is triggered via the run custom build dialog without changing anything, the 'unchecked value' is used (if not empty); and if it is empty, the default value is used

  • if the build is triggered via the run custom build dialog with the box checked, the 'checked value' is used (if not empty); and if it is empty, the 'true' value is used


Check the Allow multiple box to enable multiple selection. In the Items field specify a newline-separated list of items. Use the following syntax label => value or value.

Manually Configuring Parameter Specification

Alternatively, you can manually configure a specification using a specially formatted string with the syntax similar to the one used in service messages (typeName key='value' ).
For example, for the text label: text label='some label' regex='some pattern'.

Copying Parameter Specification

If you start editing a parameter that has a specification, you can see a link to its raw value in the Edit parameter dialog. Click it to view the specification in its raw form (in the service message format). To use this specification in another build configuration, just copy it from here, and paste in another configuration.

Modifying Parameter Specification via REST API

You can also view/edit typed parameters specification via REST API.

Last modified: 19 August 2020