This method has dynamic request argument. It depends on provided event type. See description below to get definitions of request argument for every event type.

Click suggestion event arguments:

type required ('click-suggestion'): Click suggestion event type.
request.rid required (string): Id of request, where user clicked on suggestion.
request.suggestion required (string): Suggestion title.
request.user optional (user): User object. Could be provided either at initialization or at request.

Click item event arguments:

type required ('click-item'): Click item event type.
request.item_id required (string): Id of item, which user clicked.
request.rid optional (string): Id of request, where user clicked on item.
request.user optional (user): User object. Could be provided either at initialization or at request.

Redirect event arguments:

type required ('redirect'): Redirect event type.
request.rid required (string): Id of request, where redirect was happened.
request.suggestion required (string): Suggestion that leads to the redirection.
request.user optional (user): User object. Could be provided either at initialization or at request.

Purchase event arguments:

type required ('purchase'): Purchase event type.
request.order_id required (string): Id of order.
request.currency required (string): Currency of the purchase.
request.revenue required (number): Total revenue of the purchase.
request.line_items required (line_item[]): Items in cart.
request.affiliation optional (string): Affiliation of the purchase.
request.user optional (user): User object. Could be provided either at initialization or at request.

Update cart event arguments:

type required ('update-cart'): Update cart event type.
request.line_items required (line_item[]): Items in cart.
request.user optional (user): User object. Could be provided either at initialization or at request.

Add to cart event arguments:

type required ('add-to-cart'): Add to cart event type.
request.item_id required (string): Id of item, added to cart.
request.rid optional (string): Id of request, where add to cart button was clicked.
request.quantity optional (number): Quantity of items, added to cart. Default - 1.
request.user optional (user): User object. Could be provided either at initialization or at request.

View page event arguments:

type required ('view-page'): View page event type.
request.url required (string): Url of the page viewed.
request.ref required (string): Referrer of the page.
request.width required (number): Width of the customer's browser.
request.height required (number): Height of the customer's browser.
request.item_id optional (string): Id of item. Only for product pages.
request.user optional (user): User object. Could be provided either at initialization or at request.

Types:

line_item.id required (string): Id of item.
line_item.unit_price required (string): Price of the product.
line_item.quantity required (number): Quantity of items.

user.uid required (string): Unique customer id.
user.sid required (string): Session id.
user.email optional (string): Customer email.
user.ip optional (number): Customer ip.
user.ua optional (string): Customer user agent.
user.lang optional (string[]): Languages.

Examples of usage:

// Click suggestion event
var request = {
    rid: '892',
    suggestion: 'White t-shirts'
};

client.feedback('click-suggestion', request);

// Click item event
var request = {
    rid: '892',
    item_id: '9842'
};

client.feedback('click-item', request);

// Redirect event
var request = {
    rid: '892',
    suggestion: 'T-shirt'
};

client.feedback('redirect', request);

// Purchase event
var request = {
    order_id: '451',
    currency: 'usd',
    revenue: 394.1,
    line_items: [{
        item_id: '5028',
        unit_price: 394.1,
        quantity: 2
    }]
};

client.feedback('purchase', request);

// Update cart event
var request = {
    line_items: [{
        item_id: '5028',
        unit_price: 394.1,
        quantity: 2
    }]
};

client.feedback('update-cart', request);

// Add to cart event
var request = {
    item_id: '5720',
    rid: '72046',
    quantity: 1,
};

client.feedback('add-to-cart', request);

// View page event
var request = {
    url: 'some-store.com',
    ref: 'some-referrer.com',
    width: 1366,
    height: 768,
    item_id: '8572'
};

client.feedback('view-page', request);