Get 'purchasable' from ElementAPI
Try

return [
'endpoints' =&gt; [
    'products.json' =&gt; [
        'elementType' =&gt; 'Commerce_Product',
        'criteria' =&gt; [
            // 'category' =&gt; 'products', // randomly trying stuff here!
            // 'section' =&gt; 'products',
            // 'type' =&gt; 'products',
        ],
        'transformer' =&gt; function(Commerce_ProductModel $product) {
            return [
                'title' =&gt; $product-&gt;title,
                'url' =&gt; $product-&gt;url,
            ];
        },
    ]
]]