WordPress

You need a published agent and its Embed code from Agent → Deploy → Website widget.

<script src="https://evasay.com/voice-widget.js" data-agent="AGENT_SLUG" async></script>

With a code plugin

1. Install a plugin that adds code to every page, such as WPCode (Plugins → Add New).
2. Add the embed code to the Footer section and save.

On WordPress.com, plugins and custom code need a plan that allows them.

In your theme

If you maintain your own child theme, paste the embed code just before </body> in its footer.php, or add it from functions.php:

add_action('wp_footer', function () {
    echo '<script src="https://evasay.com/voice-widget.js" data-agent="AGENT_SLUG" async></script>';
});

A theme update replaces the parent theme's files, so put the code in a child theme or a plugin.

Allow your site's addresses

Under Agent → Deploy → Allowed websites, add each address your site opens at, for example https://www.example.com and https://example.com. Then your page can pass values and functions to the agent.