Title: Blueprints Functions and the API Client
Published: July 15, 2026
Last modified: July 16, 2026

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# Blueprints Functions and the API Client

[ Back to top](https://developer.wordpress.org/playground/developers/apis/javascript-api/blueprint-functions/?output_format=md#wp--skip-link--target)

Every Blueprint step you can declare in the JSON object also provides a handler 
function that can be used directly.

For example:

    ```typescript
    const client = await startPlaygroundWeb({
        iframe: document.getElementById('wp'),
        remoteUrl: `https://playground.wordpress.net/remote.html`,
    });
    await client.isReady();

    await login(client, {
        username: 'admin',
        password: 'password',
    });

    await installPlugin(client, {
        // Resources can only be used with JSON Blueprints.
        // If you use functions, you must provide the resolved
        // file.
        pluginData: await fetch(pluginUrl),
    });
    ```

For more information and live examples visit the [Blueprints Steps page](https://developer.wordpress.org/playground/blueprints/steps).

First published

July 15, 2026

Last updated

July 16, 2026

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[ See list of changes: Blueprints Functions and the API Client ](https://developer.wordpress.org/playground/developers/apis/javascript-api/blueprint-functions/?output_format=md#)

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