Views Custom Field Handlers tokens
The first hook, hook_token_info(), is used to declare any custom tokens.

    /**
 * Implements hook_token_info().
 */
function module_name_token_info() {
  $info = array();
  // Define a new token type.
  $info['types']['my_custom_tokens'] = array(
    'name' =&gt; t('My custom tokens'),
    'description' =&gt; t('A token type for my custom tokens.'),
  );
  // Define any new tokens.
  $info['tokens']['my_custom_tokens']['my_cool_token'] = array(
    'name' =&gt; t('My cool token'),
    'description' =&gt; t('A token I use to show that I am cool.'),
  );
  return $info;
}


We are creating our own custom token type here too but if you just want to put your token in an already existing type, you can get a list of the existing tokens and types by calling token_get_info().

Now that our new token is good and defined, we just need to give it some content with hook_tokens().

     /**
     * Implements hook_tokens().
     */
    function module_name_tokens($type, $tokens, array $data = array(), array $options = array()) {
      $replacements = array();

      if ($type == 'my_custom_tokens') {
        // Loop through the available tokens.
        foreach ($tokens as $name =&gt; $original) {
          // Find our custom tokens by name.
          switch ($name) {
            case 'my_cool_token':
              // Work out the value of our token.
              $value = 'Whatever we want the token to be';
              // Give our token it's value!
              $replacements[$original] = $value;
              break;
          }
        }
      }
   return $replacements;

}


That's it! Our token should now be available and appear in the list of tokens wherever tokens are available.