> ## Documentation Index > Fetch the complete documentation index at: https://docs.commonality.co/llms.txt > Use this file to discover all available pages before exploring further. # Tags Tags are used to selectively apply [checks](/checks/introduction) and [constraints](/constraints/introduction) to packages. Tags are defined in a [package configuration](/reference/package-configuration) file located in your package's root directory. ```json commonality.json theme={null} { "tags": ["ui", "buildable", "private", "beta"] } ``` Commonality Studio is the best way to create and edit tags for packages. Start Studio in any JavaScript project by running: `npx commonality studio` Tags allow you to group packages by their purpose, concern, or domain without a tight coupling to directory structure. Below are some examples for inspiration but tags can be used to create any grouping that best suits your project. ## Tooling Tags can be used to enforce a consistent toolchain for subsets of packages. **Examples:** * Check that packages with the `buildable` tag have `build` and `dev` scripts. * Check that packages with the `testable` tag have a `test` script and a `vitest.config.ts` file. * Check that packages with the `typed` tag have `typescript` as a devDependency. ## Concern Tags can be used to create a hierarchy of packages based on their concern. **Examples:** * Enforce that no package can depend on a package with the tag `deployable`. * Enforce that packages with the tag `config` can only depend on packages also with the tag `config`. * Enforce that a database utility package with the tag `data` cannot depend on packages with the tag `ui`. ## Domain Tags can be used to create separation between teams or domains working in the same monorepo. * Limit that packages with the tag `marketing` can only depend on packages with the tag `marketing` or `shared`. ## Workflow Tags can be used to create workflows like deprecating or creating beta warnings. * Enforce that packages with the tag `high-stability` cannot depend on package with the tag `beta`. * Enforce that no package can depend on a package with the tag `deprecated`.