$runner = new Runner();
$runner->setMinAcceptableScore(0.75);
$runner->addHandler(new MyCustomHandler());
$runner->addHandler(new MyOtherHandler());
$runner->setContext($myContext);

$runner->getFirstAcceptable();

$existingKeywords = [/* your code here*/];
$runner = CorpusHandlerHelper::addCorpus(new Runner(), $existingKeywords);
$runner->setContext($userInput);
$result = $runner->getBestMatch();

if ($result->getScore() === 1.0) {
    // your code here. Example:
    //$page->addKeyword($result->getResult());
} else {
    // your code here. Example:
    //echo 'Did you mean "'.$result->getResult().'"?';
}

$runner = new Runner();
$runner->setMinAcceptableScore(0.75);
$runner->addHandler(new class implements HandlerInterface {
    public function execute($context)
    {
        // Some external request that return a score/confidence value
        $percent = doSomethingAwesome($context);
        return new HandlerResult($percent/100, $percent, $context, $this);
    }
    public function accept($context)
    {
        return true;
    }
});
$runner->addHandler(new class implements HandlerInterface {
    public function execute($context)
    {
        // Some voodoo calculation with the context
        $noteOnTen = myHardWorkCalculation($context);
        return new HandlerResult($percent/10, $noteOnTen, $context, $this);
    }
    public function accept($context)
    {
        return true;
    }
});
$runner->setContext($myContext);

$result = $runner->getFirstAcceptable();

var_dump($result);