The Wayback Machine - https://web.archive.org/web/20160617152419/https://dev.twitter.com/web/wordpress/tweet-button

Display a Tweet Button in WordPress

The Twitter plugin for WordPress supports generating a Tweet button through the twitter_shareWordPress shortcode. Add a Tweet button to a WordPress post by including the shortcode in your post content area or by evaluating a shortcode in PHP using the do_shortcode WordPress function.

Example:

Share this post:

[twitter_share]

Supported shortcode parameters

text optional

Pre-populated text highlighted in the Tweet composer.

A text value provided in a shortcode overrides the text value provided in the post editor.

Example Value: Hello world

hashtags optional

A comma-separated list of hashtags to include with the Tweet.

A hashtags value provided in a shortcode overrides the hashtags value provided in the post editor.

Example Value: cute,funny

url optional

URL included with the Tweet.

Automatically set to the permalink value for the post after passing through the twitter_url filter when executed inside the loop.

Example Value: https://example.com/

via optional

Attribute the source of a Tweet to a Twitter username.

Defaults to the Twitter username provided in the Site Attribution section of the Twitter settings page. May be overridden by the twitter_via_username filter.

Example Value: TwitterDev

in_reply_to optional

Specify a Tweet ID for a new Tweet to appear in reply to another Tweet.

Example Value: 463440424141459456

count optional

A Tweet button displays the number of Tweets referencing the specified URL to the left or right of the button by default.

Set to none to omit the Tweet count or set to vertical to display the Tweet count above the button.

Example Value: none

counturl optional

Specify a count URL to be used to count the number of Tweets referencing your URL if you have modified your share URL.

Example Value: https://example.com/

align optional

Set to left or right to force align the button inside the generated iframe.

Example Value: right

size optional

Set to large to display a larger version of the Tweet button.

Example Value: large

Site-wide customization using a filter

A website may programmatically set Tweet button parameters by acting on the associative array passed to the shortcode_atts_twitter_shareWordPress filter.

Functions acting on the filter should treat the value associated with the hashtags key as a positional array of unique values. The value associated with the related key should be treated as an associative array with keys of Twitter usernames and values describing each username (or an empty string if no description).

Example:

/**
 * Always show a large button
 *
 * @param array $options parsed options with defaults applied
 * @param array $defaults default values of a Tweet button
 * @param array $attributes user-defined shortcode attributes
 *
 * @return array options array with our customization applied
 */
function twitter_share_custom_options( $options, $defaults, $attributes )
{
  $options['size'] = 'large';
  return $options;
}
add_filter( 'shortcode_atts_twitter_share', 'twitter_share_custom_options', 10, 3 );