> For the complete documentation index, see [llms.txt](https://docs.testery.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.testery.io/get-to-know-testery/system-variables.md).

# System Variables

Testery sets System Variables that get passed to the tests as standard environment variables. They may be accessed using the standard method of accessing environment variables in your testing framework. These values may be useful to you for logging and debugging purposes.

If you're looking for how to set variables in Testery that can vary by environment and will get passed in to your test runs, see[ Environments - Variables](/get-to-know-testery/set-up-your-test-environments.md#variables).

* `IS_TESTERY` - Set to TRUE if the tests are running in the Testery platform. Useful for writing tests that perform differently when running in the platform.
* `TESTERY_CHROME_ARGS` - Arguments that should be passed to Chrome if you are manually launching it in your tests.
* `TESTERY_TEST_RUN_KEY` - A unique key string given to each test run.
* `TESTERY_TEST_RUN_ID` - A unique numeric id given to each test run.
* `TESTERY_ENVIRONMENT_URL` - The Environment URL set on the Environment. See Setting Up Environments.


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