> For the complete documentation index, see [llms.txt](https://docs.brainboard.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.brainboard.co/cloud-design/left-bar/input-and-output/variables.md). # Variables ### Variables In **Terraform**, a variable is a way to store and reuse values throughout your **Terraform** code, and it is defined using the **`variable`** block. {% hint style="info" %} Brainboard allows you to create a variable **manually,** or you can also import it from an existing file. File types allowed are: **`tfvars`** , **`tf`**. {% endhint %} {% hint style="success" %} **Brainboard** follows **Terraform** best practices, so by default, when you create a new architecture, Brainboard automatically adds a variable called **`tags`** which is added in the generated **Terraform** code of every resource that supports tagging. {% endhint %} #### Action items on the Variables window Shared below is the screenshot of the **Variables** window, numbered with action items/features available on this screen, followed by their brief description. {% hint style="info" %} By default, the variables list is displayed when you click on the **variables icon** in the right panel. {% endhint %}

#	Feature	Purpose / Description
₁	_{Add Variable (+)}	_{To create a new variable. (Explained in detail below).}
₂	_{Search option}	_{To search for a specific variable on the Variables window. Keyword search is supported.}
₃	_Filter	_{Using this option, you can filter the list of variables by scope or by the user who updated the variable. So, you have the following three options:} _{- All (no filter).} _{- Scope: architecture, environment, project, organization.} _{- Updated by: select the user name whose updated variables you want to view.}
₄	_{Sorting variables list}	_{You can sort the list of variables according to ascending or descending order of their names, as well as in ascending/descending order of the date when they were last updated.}
₅	_Filter	_{The scope selector allows you to view variables that are defined in every scope or display all variables of all scopes.}
₆	_{Expand all / Collapse all}	_{Clicking this will exapnd the variables section for you to view details of each variable in the list. Clicking it again will collapse the expanded view.}

#### Creating a new variable To create a new variable, expand the right panel, and follow these steps: 1. Click the **`Variable`** icon available in the right panel. 2. Then, click the **`+`** icon to add/import variables. It opens the **Create** **Variable** modal.

3. After that, you can either create a variable **manually** or you can click on the **`Import`** option to **import** already defined variables from an external file (**`tfvars`** , **`tf`** ).

On the ***"Create variable"*** form, you can specify the following information: 1. **Name of the variable:** This is the name that you'll use to reference the variable when you use it. {% hint style="info" %} It follows the naming conventions of **Terraform**; for example, it doesn't support spaces or starting with a number. **Best practice:** use clear and explicit names and separate words with an underscore **`_`**. {% endhint %} 2. **Scope:** You can set the level at which you want this variable to be available.

{% hint style="info" %} The four levels of scopes are listed in the order of **"least shared or restrictive to most shared/available/"** {% endhint %} {% hint style="info" %} There is an override mechanism if the same variable is defined in multiple scopes. {% endhint %}

Scope	Explanation	Variable Override
_Architecture	_{Variables that are defined with this scope are only available within this architecture only.}	_{If the same variable is defined in another level as well, the default or values defined at the architecture level overrides any other level.}
_Environment	_{Variables defined at the environment level are available to all architectures within the same environment.}	_{Variables defined in this level override those defined at project and organization level.}
_Project	_{Variables defined at the project level are available to all environments and architectures within the same project.}	_{Variables defined in this level override those defined at the organization level.}
_Organization	_{Variables defined at the organization level are available to all architectures, environments and project within the organization.}

3. **Description:** It should concisely explain the purpose of the variable and what kind of value is expected. This description string might be included in documentation about the module, and so it should be written from the perspective of the user of the module rather than its maintainer. 4. **Variable type:** This allows you to restrict the type of value that will be accepted. {% hint style="info" %} If no type constraint is set, then a value of any type is accepted. {% endhint %} While type constraints are optional, we recommend specifying them; they can serve as helpful reminders for users of the module, and they allow **Terraform** to return a helpful error message if the wrong type is used. {% hint style="success" %} The supported type keywords are: **`any`** **`bool`** **`list`** **`map`** **`number`** **`object`** **`set`** **`string`** **`tuple`** {% endhint %}

5. **Default value:** If present, the variable is considered to be *optional* and the default value will be used if no value is set. 6. **Value:** The value that will be used during **Terraform** execution and if defined, it overrides the default value. 1. This value will be put in the file **`terraform.tfvars`** . 2. If you convert the architecture into a template or clone the architecture, this value will be removed. 7. **Sensitive:** Setting this flag prevents **Terraform** from showing its value in the **`plan`** or **`apply`** output and **Brainboard** will store the variable in a separate vault. {% hint style="warning" %} Even if the variable is flagged sensitive, its value will still be stored in clear text in the **Terraform** state. {% endhint %} 8. **Validation:** You can specify custom validation rules for the variable.

{% hint style="success" %} For every variable defined, Brainboard creates a variable block in the file **`variables.tf`**** ****.** {% endhint %} {% hint style="info" %} Refer to the [RBAC (Role Based Access Control) documentation page](/settings/rbac.md) to understand how you can manage permissions to restrict/allow members and teams to add, update or delete variables. {% endhint %} --- # Agent Instructions This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com. ## 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.brainboard.co/cloud-design/left-bar/input-and-output/variables.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.