diff --git a/README.md b/README.md
index a37087a8e..ebf91b7f1 100644
--- a/README.md
+++ b/README.md
@@ -1,13 +1,13 @@
-# Codecov GitHub Action 
+# Codecov GitHub Action
 
 [![GitHub Marketplace](https://img.shields.io/badge/Marketplace-v1-undefined.svg?logo=github&logoColor=white&style=flat)](https://github.com/marketplace/actions/codecov)
-### Easily upload coverage reports to Codecov from GitHub Actions 
+### Easily upload coverage reports to Codecov from GitHub Actions
 
 >The latest release of this Action adds support for tokenless uploads from GitHub Actions!
 
 ## Usage
 
-To integrate Codecov with your Actions pipeline, specify the name of this repository with a tag number (`@v1` is recommended) as a `step` within your `workflow.yml` file. 
+To integrate Codecov with your Actions pipeline, specify the name of this repository with a tag number (`@v1` is recommended) as a `step` within your `workflow.yml` file.
 
 If you have a *private repository*, this Action also requires you to [provide an upload token](https://docs.codecov.io/docs/frequently-asked-questions#section-where-is-the-repository-upload-token-found-) from [codecov.io](https://www.codecov.io) (tip: in order to avoid exposing your token, store it as a `secret`). Optionally, you can choose to include up to four additional inputs to customize the upload context. **For public repositories, no token is needed**
 
@@ -24,11 +24,11 @@ steps:
     name: codecov-umbrella # optional
     fail_ci_if_error: true # optional (default = false)
 ```
->**Note**: This assumes that you've set your Codecov token inside *Settings > Secrets* as `CODECOV_TOKEN`. If not, you can [get an upload token](https://docs.codecov.io/docs/frequently-asked-questions#section-where-is-the-repository-upload-token-found-) for your specific repo on [codecov.io](https://www.codecov.io). Keep in mind that secrets are *not* available to forks of repositories. 
+>**Note**: This assumes that you've set your Codecov token inside *Settings > Secrets* as `CODECOV_TOKEN`. If not, you can [get an upload token](https://docs.codecov.io/docs/frequently-asked-questions#section-where-is-the-repository-upload-token-found-) for your specific repo on [codecov.io](https://www.codecov.io). Keep in mind that secrets are *not* available to forks of repositories.
 
 ## Arguments
 
-Codecov's Action currently supports five inputs from the user: `token`, `file`, `flags`,`name`, and `fail_ci_if_error`. These inputs, along with their descriptions and usage contexts, are listed in the table below: 
+Codecov's Action currently supports five inputs from the user: `token`, `file`, `flags`,`name`, and `fail_ci_if_error`. These inputs, along with their descriptions and usage contexts, are listed in the table below:
 
 >**Update**: We've removed the `yml` paramter with the latest release of this action. Please put your custom codecov yaml file at the root of the repo because other locations will no longer be supported in the future.
 
@@ -37,7 +37,7 @@ Codecov's Action currently supports five inputs from the user: `token`, `file`,
 | `token`  | Used to authorize coverage report uploads  | *Required for private repos* |
 | `file`  | Path to the coverage report(s) | Optional
 | `flags`  | Flag the upload to group coverage metrics (unittests, uitests, etc.). Multiple flags are separated by a comma (ui,chrome) | Optional
-| `env_vars`  | Environment variable to take the upload with. Multiple env variables can be multiple separated with commas (e.g. `OS,PYTHON`) | Optional
+| `env_vars`  | Environment variables to tag the upload with. Multiple env variables can be separated with commas (e.g. `OS,PYTHON`) | Optional
 | `name`  | Custom defined name for the upload | Optional
 | `fail_ci_if_error`  | Specify if CI pipeline should fail when Codecov runs into errors during upload. *Defaults to **false*** | Optional
 
@@ -50,14 +50,14 @@ jobs:
   run:
     runs-on: ${{ matrix.os }}
     strategy:
-      matrix: 
+      matrix:
         os: [ubuntu-latest, macos-latest, windows-latest]
     env:
       OS: ${{ matrix.os }}
       PYTHON: '3.7'
     steps:
     - uses: actions/checkout@master
-    - name: Setup Python  
+    - name: Setup Python
       uses: actions/setup-python@master
       with:
         python-version: 3.7
@@ -66,7 +66,7 @@ jobs:
         pip install pytest
         pip install pytest-cov
         pytest --cov=./ --cov-report=xml
-    - name: Upload coverage to Codecov  
+    - name: Upload coverage to Codecov
       uses: codecov/codecov-action@v1
       with:
         token: ${{ secrets.CODECOV_TOKEN }}
@@ -80,6 +80,6 @@ jobs:
 
 Contributions are welcome! Check out the [Contribution Guide](CONTRIBUTING.md).
 
-## License 
+## License
 
 The code in this project is released under the [MIT License](LICENSE).
diff --git a/action.yml b/action.yml
index 4cf1211b5..6b2854452 100644
--- a/action.yml
+++ b/action.yml
@@ -1,13 +1,13 @@
 name: 'Codecov'
 description: 'GitHub Action that uploads coverage reports for your repository to codecov.io'
 author: 'Ibrahim Ali <@ibrahim0814> | Codecov'
-inputs: 
+inputs:
   name:
     description: 'User defined upload name. Visible in Codecov UI'
-    required: false 
+    required: false
   token:
     description: 'Repository upload token - get it from codecov.io. Required only for private repositories'
-    required: false 
+    required: false
   file:
     description: 'Path to coverage file to upload'
     required: false
@@ -15,15 +15,14 @@ inputs:
     description: 'Flag upload to group coverage metrics (e.g. unittests | integration | ui,chrome)'
     required: false
   env_vars:
-    description: 'Environment variable to take the upload with, can be multiple separated with commas'
+    description: 'Environment variables to tag the upload with (e.g. PYTHON | OS,PYTHON)'
     required: false
   fail_ci_if_error:
     description: 'Specify whether or not CI build should fail if Codecov runs into an error during upload'
     required: false
 branding:
-  color: 'red' 
+  color: 'red'
   icon: 'umbrella'
 runs:
   using: 'node12'
   main: 'dist/index.js'
-   
diff --git a/dist/index.js b/dist/index.js
index 201c66c15..a40317e5b 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -2342,7 +2342,7 @@ try {
   const token = core.getInput("token");
   const flags = core.getInput("flags");
   const file = core.getInput("file");
-  let env_vars = core.getInput("env_vars");
+  const env_vars = core.getInput("env_vars");
   fail_ci = core.getInput("fail_ci_if_error").toLowerCase();
 
   if (
diff --git a/index.js b/index.js
index fcc49b8bb..d7f759976 100644
--- a/index.js
+++ b/index.js
@@ -9,7 +9,7 @@ try {
   const token = core.getInput("token");
   const flags = core.getInput("flags");
   const file = core.getInput("file");
-  let env_vars = core.getInput("env_vars");
+  const env_vars = core.getInput("env_vars");
   fail_ci = core.getInput("fail_ci_if_error").toLowerCase();
 
   if (