diff --git a/build/kint.phar b/build/kint.phar
index ddd666fe9..0a41abd8d 100644
Binary files a/build/kint.phar and b/build/kint.phar differ
diff --git a/src/CallFinder.php b/src/CallFinder.php
index f85b1ae01..cfa1921ac 100644
--- a/src/CallFinder.php
+++ b/src/CallFinder.php
@@ -248,15 +248,15 @@ public static function getFunctionCalls(string $source, int $line, $function): a
 
             // Check if it matches the signature
             if (null === $class) {
-                if ($prev_tokens[1] && isset(self::$classcalls[$prev_tokens[1][0]])) {
+                if (null !== $prev_tokens[1] && isset(self::$classcalls[$prev_tokens[1][0]])) {
                     continue;
                 }
             } else {
-                if (!$prev_tokens[1] || T_DOUBLE_COLON !== $prev_tokens[1][0]) {
+                if (null === $prev_tokens[1] || T_DOUBLE_COLON !== $prev_tokens[1][0]) {
                     continue;
                 }
 
-                if (!$prev_tokens[0] || !isset(self::$namespace[$prev_tokens[0][0]])) {
+                if (null === $prev_tokens[0] || !isset(self::$namespace[$prev_tokens[0][0]])) {
                     continue;
                 }
 
@@ -539,20 +539,21 @@ private static function tokensFormatted(array $tokens): array
                 $next = $tokens[$next];
 
                 /** @psalm-var PhpToken $last */
+                // Since we call tokensTrim we know we can't be here without a $last */
                 if ($attribute && ']' === $last[0]) {
                     $attribute = false;
                 } elseif (!$ignorestrip && isset(self::$strip[$last[0]]) && !self::tokenIsOperator($next)) {
                     continue;
                 }
 
-                if (!$ignorestrip && isset(self::$strip[$next[0]]) && $last && !self::tokenIsOperator($last)) {
+                if (!$ignorestrip && isset(self::$strip[$next[0]]) && !self::tokenIsOperator($last)) {
                     continue;
                 }
 
                 $token = ' ';
                 $space = true;
             } else {
-                if (KINT_PHP80 && $last && T_ATTRIBUTE == $last[0]) {
+                if (KINT_PHP80 && null !== $last && T_ATTRIBUTE == $last[0]) {
                     $attribute = true;
                 }
 
diff --git a/src/Kint.php b/src/Kint.php
index 40d37689b..614731939 100644
--- a/src/Kint.php
+++ b/src/Kint.php
@@ -411,6 +411,8 @@ public static function getBasesFromParamInfo(array $params, int $argc): array
      * @param array   $args    Arguments
      *
      * @return array Call info
+     *
+     * @psalm-param list<non-empty-array> $trace
      */
     public static function getCallInfo(array $aliases, array $trace, array $args): array
     {
@@ -456,7 +458,7 @@ public static function getCallInfo(array $aliases, array $trace, array $args): a
             'trace' => $miniTrace,
         ];
 
-        if ($call) {
+        if (null !== $call) {
             $ret['params'] = $call['parameters'];
             $ret['modifiers'] = $call['modifiers'];
         }
@@ -648,7 +650,7 @@ protected static function getSingleCall(array $frame, array $args): ?array
         if (
             !isset($frame['file'], $frame['line'], $frame['function']) ||
             !\is_readable($frame['file']) ||
-            !$source = \file_get_contents($frame['file'])
+            false === ($source = \file_get_contents($frame['file']))
         ) {
             return null;
         }
diff --git a/src/Parser/ClassMethodsPlugin.php b/src/Parser/ClassMethodsPlugin.php
index e71d537aa..8b90300ae 100644
--- a/src/Parser/ClassMethodsPlugin.php
+++ b/src/Parser/ClassMethodsPlugin.php
@@ -61,6 +61,7 @@ public function parse(&$var, Value &$o, int $trigger): void
                 $methods[] = new MethodValue($method);
             }
 
+            /** @psalm-suppress InvalidArgument */
             \usort($methods, ['Kint\\Parser\\ClassMethodsPlugin', 'sort']);
 
             self::$cache[$class] = $methods;
@@ -68,6 +69,7 @@ public function parse(&$var, Value &$o, int $trigger): void
 
         if (!empty(self::$cache[$class])) {
             $rep = new Representation('Available methods', 'methods');
+            $rep->contents = [];
 
             // Can't cache access paths
             foreach (self::$cache[$class] as $m) {
diff --git a/src/Parser/ClassStaticsPlugin.php b/src/Parser/ClassStaticsPlugin.php
index 5435da932..5a063b1d3 100644
--- a/src/Parser/ClassStaticsPlugin.php
+++ b/src/Parser/ClassStaticsPlugin.php
@@ -87,6 +87,7 @@ public function parse(&$var, Value &$o, int $trigger): void
                     $const->access_path = '\\'.$class.'::'.$name;
                 }
 
+                /** @psalm-var Value */
                 $const = $this->parser->parse($val, $const);
 
                 $consts[] = $const;
@@ -96,7 +97,8 @@ public function parse(&$var, Value &$o, int $trigger): void
         }
 
         $statics = new Representation('Static class properties', 'statics');
-        $statics->contents = self::$cache[$class];
+        /** @psalm-var list<Value> */
+        $statics->contents = self::$cache[$class] ?? [];
 
         foreach ($reflection->getProperties(ReflectionProperty::IS_STATIC) as $static) {
             $prop = new Value();
@@ -124,6 +126,7 @@ public function parse(&$var, Value &$o, int $trigger): void
                 $statics->contents[] = $prop;
             } else {
                 $static = $static->getValue();
+                /** @psalm-var Value */
                 $statics->contents[] = $this->parser->parse($static, $prop);
             }
         }
@@ -132,6 +135,7 @@ public function parse(&$var, Value &$o, int $trigger): void
             return;
         }
 
+        /** @psalm-suppress InvalidArgument */
         \usort($statics->contents, ['Kint\\Parser\\ClassStaticsPlugin', 'sort']);
 
         $o->addRepresentation($statics);
diff --git a/src/Parser/DOMDocumentPlugin.php b/src/Parser/DOMDocumentPlugin.php
index 84cfbf835..90afb91ab 100644
--- a/src/Parser/DOMDocumentPlugin.php
+++ b/src/Parser/DOMDocumentPlugin.php
@@ -154,6 +154,7 @@ protected function parseList($var, InstanceValue &$o, int $trigger): void
         }
 
         $r = new Representation('Iterator');
+        $r->contents = [];
         $o->replaceRepresentation($r, 0);
 
         foreach ($var as $key => $item) {
@@ -222,6 +223,7 @@ protected function parseNode(DOMNode $var, InstanceValue &$o): void
         $attributes = null;
 
         $rep = $o->value;
+        $rep->contents = [];
 
         foreach ($known_properties as $prop) {
             $prop_obj = $this->parseProperty($o, $prop, $var);
@@ -250,15 +252,14 @@ protected function parseNode(DOMNode $var, InstanceValue &$o): void
         // Set the attributes
         if ($attributes) {
             $a = new Representation('Attributes');
-            foreach ($attributes->contents as $attribute) {
-                $a->contents[] = $attribute;
-            }
+            $a->contents = $attributes->contents;
             $o->addRepresentation($a, 0);
         }
 
         // Set the children
-        if ($childNodes) {
+        if ($childNodes && \is_array($childNodes->contents)) {
             $c = new Representation('Children');
+            $c->contents = [];
 
             if (1 === \count($childNodes->contents) && ($node = \reset($childNodes->contents)) && \in_array('depth_limit', $node->hints, true)) {
                 $n = new InstanceValue();
@@ -278,9 +279,7 @@ protected function parseNode(DOMNode $var, InstanceValue &$o): void
             }
 
             $o->addRepresentation($c, 0);
-        }
 
-        if ($childNodes) {
             $o->size = \count($childNodes->contents);
         }
 
diff --git a/src/Parser/Parser.php b/src/Parser/Parser.php
index 1767eaa3f..7e4d14355 100644
--- a/src/Parser/Parser.php
+++ b/src/Parser/Parser.php
@@ -321,6 +321,7 @@ private function parseArray(array &$var, Value $o): Value
         }
 
         $rep = new Representation('Contents');
+        $rep->contents = [];
         $rep->implicit_label = true;
         $array->addRepresentation($rep);
         $array->value = $rep;
@@ -442,6 +443,7 @@ private function parseObject(&$var, Value $o): Value
         }
 
         $rep = new Representation('Properties');
+        $rep->contents = [];
 
         $readonly = [];
 
diff --git a/src/Parser/SimpleXMLElementPlugin.php b/src/Parser/SimpleXMLElementPlugin.php
index db6f9b9c1..275f4f282 100644
--- a/src/Parser/SimpleXMLElementPlugin.php
+++ b/src/Parser/SimpleXMLElementPlugin.php
@@ -79,6 +79,7 @@ public function parse(&$var, Value &$o, int $trigger): void
 
         // Attributes
         $a = new Representation('Attributes');
+        $a->contents = [];
 
         $base_obj = new Value();
         $base_obj->depth = $x->depth;
@@ -96,6 +97,7 @@ public function parse(&$var, Value &$o, int $trigger): void
         $attribs = [];
 
         foreach ($namespaces as $nsAlias => $nsUrl) {
+            /** @psalm-suppress RiskyTruthyFalsyComparison */
             if ($nsAttribs = $var->attributes($nsUrl)) {
                 $cleanAttribs = [];
                 foreach ($nsAttribs as $name => $attrib) {
@@ -131,6 +133,7 @@ public function parse(&$var, Value &$o, int $trigger): void
 
         // Children
         $c = new Representation('Children');
+        $c->contents = [];
 
         foreach ($namespaces as $nsAlias => $nsUrl) {
             // This is doubling items because of the root namespace
@@ -140,6 +143,7 @@ public function parse(&$var, Value &$o, int $trigger): void
                 continue;
             }
 
+            /** @psalm-suppress RiskyTruthyFalsyComparison */
             if ($nsChildren = $var->children($nsUrl)) {
                 $nsap = [];
                 foreach ($nsChildren as $name => $child) {
diff --git a/src/Parser/TracePlugin.php b/src/Parser/TracePlugin.php
index a5f47dcfc..c699e20c9 100644
--- a/src/Parser/TracePlugin.php
+++ b/src/Parser/TracePlugin.php
@@ -82,7 +82,7 @@ public function parse(&$var, Value &$o, int $trigger): void
                 continue;
             }
 
-            if (isset($trace[$index]['file']) && ($realfile = \realpath($trace[$index]['file']))) {
+            if (isset($trace[$index]['file']) && false !== ($realfile = \realpath($trace[$index]['file']))) {
                 foreach ($path_blacklist as $path) {
                     if (0 === \strpos($realfile, $path)) {
                         continue 2;
diff --git a/src/Parser/XmlPlugin.php b/src/Parser/XmlPlugin.php
index a5a31abd4..a17977654 100644
--- a/src/Parser/XmlPlugin.php
+++ b/src/Parser/XmlPlugin.php
@@ -124,7 +124,7 @@ protected static function xmlToSimpleXML(string $var, ?string $parent_path): ?ar
     protected static function xmlToDOMDocument(string $var, ?string $parent_path): ?array
     {
         // There's no way to check validity in DOMDocument without making errors. For shame!
-        if (!self::xmlToSimpleXML($var, $parent_path)) {
+        if (null === self::xmlToSimpleXML($var, $parent_path)) {
             return null;
         }
 
diff --git a/src/Renderer/CliRenderer.php b/src/Renderer/CliRenderer.php
index c2ea103b6..774b34743 100644
--- a/src/Renderer/CliRenderer.php
+++ b/src/Renderer/CliRenderer.php
@@ -71,6 +71,7 @@ class CliRenderer extends TextRenderer
 
     protected static $terminal_width = null;
 
+    /** @var bool */
     protected $windows_output = false;
 
     protected $colors = false;
@@ -100,7 +101,10 @@ public function __construct()
         if (!self::$terminal_width) {
             if (!KINT_WIN && self::$detect_width) {
                 try {
-                    self::$terminal_width = (int) \exec('tput cols');
+                    $tput = \exec('tput cols');
+                    if (false !== $tput) {
+                        self::$terminal_width = (int) $tput;
+                    }
                 } catch (Throwable $t) {
                     self::$terminal_width = self::$default_width;
                 }
diff --git a/src/Renderer/Rich/AbstractPlugin.php b/src/Renderer/Rich/AbstractPlugin.php
index 4d9ec7067..082976c74 100644
--- a/src/Renderer/Rich/AbstractPlugin.php
+++ b/src/Renderer/Rich/AbstractPlugin.php
@@ -50,7 +50,7 @@ public function renderLockedHeader(Value $o, string $content): string
     {
         $header = '<dt class="kint-parent kint-locked">';
 
-        if (RichRenderer::$access_paths && $o->depth > 0 && $ap = $o->getAccessPath()) {
+        if (RichRenderer::$access_paths && $o->depth > 0 && null !== ($ap = $o->getAccessPath())) {
             $header .= '<span class="kint-access-path-trigger" title="Show access path">&rlarr;</span>';
         }
 
diff --git a/src/Renderer/Rich/CallablePlugin.php b/src/Renderer/Rich/CallablePlugin.php
index 744380524..8ca45399b 100644
--- a/src/Renderer/Rich/CallablePlugin.php
+++ b/src/Renderer/Rich/CallablePlugin.php
@@ -74,7 +74,7 @@ protected function renderMethod(MethodValue $o): string
             $header .= '<var>'.$s;
 
             if ($o->return_reference) {
-                if ($s) {
+                if (\is_string($s) && \strlen($s)) {
                     $header .= ' ';
                 }
                 $header .= $this->renderer->escape('&');
diff --git a/src/Renderer/Rich/MethodDefinitionPlugin.php b/src/Renderer/Rich/MethodDefinitionPlugin.php
index f5ed37b62..f137300ad 100644
--- a/src/Renderer/Rich/MethodDefinitionPlugin.php
+++ b/src/Renderer/Rich/MethodDefinitionPlugin.php
@@ -39,7 +39,7 @@ public function renderTab(Representation $r): ?string
             return null;
         }
 
-        if (isset($r->contents)) {
+        if (\is_string($r->contents)) {
             $docstring = [];
             foreach (\explode("\n", $r->contents) as $line) {
                 $docstring[] = \trim($line);
diff --git a/src/Renderer/Rich/SimpleXMLElementPlugin.php b/src/Renderer/Rich/SimpleXMLElementPlugin.php
index 87d987079..c4dec62f6 100644
--- a/src/Renderer/Rich/SimpleXMLElementPlugin.php
+++ b/src/Renderer/Rich/SimpleXMLElementPlugin.php
@@ -39,6 +39,7 @@ public function renderValue(Value $o): ?string
             return null;
         }
 
+        /** @psalm-suppress RiskyTruthyFalsyComparison */
         if (!$o->isStringValue() || !empty($o->getRepresentation('attributes')->contents)) {
             return null;
         }
diff --git a/src/Renderer/Rich/TablePlugin.php b/src/Renderer/Rich/TablePlugin.php
index 80fdd10f1..653342aa1 100644
--- a/src/Renderer/Rich/TablePlugin.php
+++ b/src/Renderer/Rich/TablePlugin.php
@@ -35,8 +35,12 @@ class TablePlugin extends AbstractPlugin implements TabPluginInterface
 {
     public static $respect_str_length = true;
 
-    public function renderTab(Representation $r): string
+    public function renderTab(Representation $r): ?string
     {
+        if (!\is_array($r->contents)) {
+            return null;
+        }
+
         $out = '<pre><table><thead><tr><th></th>';
 
         $firstrow = \reset($r->contents);
@@ -51,6 +55,7 @@ public function renderTab(Representation $r): string
 
         $out .= '</tr></thead><tbody>';
 
+        /** $psalm-var \Kint\Zval\Value[] $r->contents */
         foreach ($r->contents as $row) {
             $out .= '<tr><th>';
             if (null !== ($s = $row->getName())) {
diff --git a/src/Renderer/Rich/TimestampPlugin.php b/src/Renderer/Rich/TimestampPlugin.php
index 43abfb60e..226db2b91 100644
--- a/src/Renderer/Rich/TimestampPlugin.php
+++ b/src/Renderer/Rich/TimestampPlugin.php
@@ -35,7 +35,7 @@ class TimestampPlugin extends AbstractPlugin implements TabPluginInterface
 {
     public function renderTab(Representation $r): ?string
     {
-        if ($dt = DateTime::createFromFormat('U', (string) $r->contents)) {
+        if (\is_scalar($r->contents) && ($dt = DateTime::createFromFormat('U', (string) $r->contents))) {
             return '<pre>'.$dt->setTimeZone(new DateTimeZone('UTC'))->format('Y-m-d H:i:s T').'</pre>';
         }
 
diff --git a/src/Renderer/RichRenderer.php b/src/Renderer/RichRenderer.php
index b3d86ea1d..fa2cda7b9 100644
--- a/src/Renderer/RichRenderer.php
+++ b/src/Renderer/RichRenderer.php
@@ -269,7 +269,7 @@ public function renderHeaderWrapper(Value $o, bool $has_children, string $conten
 
         $out .= '>';
 
-        if (self::$access_paths && $o->depth > 0 && ($ap = $o->getAccessPath())) {
+        if (self::$access_paths && $o->depth > 0 && null !== ($ap = $o->getAccessPath())) {
             $out .= '<span class="kint-access-path-trigger" title="Show access path">&rlarr;</span>';
         }
 
@@ -304,7 +304,7 @@ public function renderHeader(Value $o): string
         if (null !== ($s = $o->getName())) {
             $output .= '<dfn>'.$this->escape($s).'</dfn> ';
 
-            if ($s = $o->getOperator()) {
+            if (null !== ($s = $o->getOperator())) {
                 $output .= $this->escape($s, 'ASCII').' ';
             }
         }
diff --git a/src/Utils.php b/src/Utils.php
index 545709586..2f73beb8c 100644
--- a/src/Utils.php
+++ b/src/Utils.php
@@ -52,6 +52,8 @@ private function __construct()
      * @param int $value Amount of bytes
      *
      * @return array Human readable value and unit
+     *
+     * @psalm-return array{value: float, unit: 'B'|'KB'|'MB'|'GB'|'TB'}
      */
     public static function getHumanReadableBytes(int $value): array
     {
diff --git a/src/Zval/BlobValue.php b/src/Zval/BlobValue.php
index 026c14378..32f267d18 100644
--- a/src/Zval/BlobValue.php
+++ b/src/Zval/BlobValue.php
@@ -130,7 +130,7 @@ public static function strlen(string $string, $encoding = false): int
                 $encoding = self::detectEncoding($string);
             }
 
-            if ($encoding && 'ASCII' !== $encoding) {
+            if (false !== $encoding && 'ASCII' !== $encoding) {
                 return \mb_strlen($string, $encoding);
             }
         }
@@ -148,7 +148,7 @@ public static function substr(string $string, int $start, ?int $length = null, $
                 $encoding = self::detectEncoding($string);
             }
 
-            if ($encoding && 'ASCII' !== $encoding) {
+            if (false !== $encoding && 'ASCII' !== $encoding) {
                 return \mb_substr($string, $start, $length, $encoding);
             }
         }
@@ -167,7 +167,8 @@ public static function substr(string $string, int $start, ?int $length = null, $
     public static function detectEncoding(string $string)
     {
         if (\function_exists('mb_detect_encoding')) {
-            if ($ret = \mb_detect_encoding($string, self::$char_encodings, true)) {
+            $ret = \mb_detect_encoding($string, self::$char_encodings, true);
+            if (false !== $ret) {
                 return $ret;
             }
         }
diff --git a/src/Zval/MethodValue.php b/src/Zval/MethodValue.php
index 55c320981..e3e0dd10a 100644
--- a/src/Zval/MethodValue.php
+++ b/src/Zval/MethodValue.php
@@ -58,7 +58,8 @@ public function __construct(ReflectionFunctionAbstract $method)
         $this->startline = $method->getStartLine();
         $this->endline = $method->getEndLine();
         $this->internal = $method->isInternal();
-        $this->docstring = $method->getDocComment() ?: null;
+        $ds = $method->getDocComment();
+        $this->docstring = false === $ds ? null : $ds;
         $this->return_reference = $method->returnsReference();
 
         foreach ($method->getParameters() as $param) {
@@ -149,7 +150,7 @@ public function getValueShort(): ?string
 
         $ds = $this->value->getDocstringWithoutComments();
 
-        if (!$ds) {
+        if (null === $ds) {
             return null;
         }
 
diff --git a/src/Zval/ParameterValue.php b/src/Zval/ParameterValue.php
index fa9d05ef5..a30f3753a 100644
--- a/src/Zval/ParameterValue.php
+++ b/src/Zval/ParameterValue.php
@@ -41,9 +41,7 @@ public function __construct(ReflectionParameter $param)
     {
         parent::__construct();
 
-        if ($type = $param->getType()) {
-            $this->type_hint = Utils::getTypeString($type);
-        }
+        $this->type_hint = ($type = $param->getType()) ? Utils::getTypeString($type) : null;
 
         $this->reference = $param->isPassedByReference();
         $this->name = $param->getName();
@@ -73,9 +71,12 @@ public function __construct(ReflectionParameter $param)
                     $this->default = \gettype($default);
                     break;
             }
+        } else {
+            $this->default = null;
         }
     }
 
+    /** @psalm-return ?truthy-string */
     public function getType(): ?string
     {
         return $this->type_hint;
@@ -86,6 +87,7 @@ public function getName(): string
         return '$'.$this->name;
     }
 
+    /** @psalm-return ?truthy-string */
     public function getDefault(): ?string
     {
         return $this->default;
diff --git a/src/Zval/Representation/ColorRepresentation.php b/src/Zval/Representation/ColorRepresentation.php
index 806a80066..80e419695 100644
--- a/src/Zval/Representation/ColorRepresentation.php
+++ b/src/Zval/Representation/ColorRepresentation.php
@@ -41,6 +41,7 @@ class ColorRepresentation extends Representation
     public const COLOR_HEX_4 = 8;
     public const COLOR_HEX_8 = 9;
 
+    /** @psalm-var array<truthy-string, truthy-string> */
     public static $color_map = [
         'aliceblue' => 'f0f8ff',
         'antiquewhite' => 'faebd7',
@@ -211,6 +212,11 @@ public function __construct(string $value)
         $this->setValues($value);
     }
 
+    /**
+     * @psalm-param ?positive-int $variant
+     *
+     * @psalm-return ?truthy-string
+     */
     public function getColor(?int $variant = null): ?string
     {
         if (!$variant) {
@@ -225,6 +231,7 @@ public function getColor(?int $variant = null): ?string
                 return \array_search($hex, self::$color_map, true) ?: \array_search($hex_alpha, self::$color_map, true) ?: null;
             case self::COLOR_HEX_3:
                 if (0 === $this->r % 0x11 && 0 === $this->g % 0x11 && 0 === $this->b % 0x11) {
+                    /** @psalm-var truthy-string */
                     return \sprintf(
                         '#%1X%1X%1X',
                         \round($this->r / 0x11),
@@ -235,28 +242,36 @@ public function getColor(?int $variant = null): ?string
 
                 return null;
             case self::COLOR_HEX_6:
+                /** @psalm-var truthy-string */
                 return \sprintf('#%02X%02X%02X', $this->r, $this->g, $this->b);
             case self::COLOR_RGB:
                 if (1.0 === $this->a) {
+                    /** @psalm-var truthy-string */
                     return \sprintf('rgb(%d, %d, %d)', $this->r, $this->g, $this->b);
                 }
 
+                /** @psalm-var truthy-string */
                 return \sprintf('rgb(%d, %d, %d, %s)', $this->r, $this->g, $this->b, \round($this->a, 4));
             case self::COLOR_RGBA:
+                /** @psalm-var truthy-string */
                 return \sprintf('rgba(%d, %d, %d, %s)', $this->r, $this->g, $this->b, \round($this->a, 4));
             case self::COLOR_HSL:
                 $val = self::rgbToHsl($this->r, $this->g, $this->b);
                 if (1.0 === $this->a) {
+                    /** @psalm-var truthy-string */
                     return \vsprintf('hsl(%d, %d%%, %d%%)', $val);
                 }
 
+                /** @psalm-var truthy-string */
                 return \sprintf('hsl(%d, %d%%, %d%%, %s)', $val[0], $val[1], $val[2], \round($this->a, 4));
             case self::COLOR_HSLA:
                 $val = self::rgbToHsl($this->r, $this->g, $this->b);
 
+                /** @psalm-var truthy-string */
                 return \sprintf('hsla(%d, %d%%, %d%%, %s)', $val[0], $val[1], $val[2], \round($this->a, 4));
             case self::COLOR_HEX_4:
                 if (0 === $this->r % 0x11 && 0 === $this->g % 0x11 && 0 === $this->b % 0x11 && 0 === ((int) ($this->a * 255)) % 0x11) {
+                    /** @psalm-var truthy-string */
                     return \sprintf(
                         '#%1X%1X%1X%1X',
                         \round($this->r / 0x11),
@@ -269,6 +284,7 @@ public function getColor(?int $variant = null): ?string
                 return null;
 
             case self::COLOR_HEX_8:
+                /** @psalm-var truthy-string */
                 return \sprintf('#%02X%02X%02X%02X', $this->r, $this->g, $this->b, \round($this->a * 0xFF));
         }
 
@@ -332,6 +348,7 @@ protected function setValues(string $value): void
         }
     }
 
+    /** @psalm-return ?positive-int */
     protected function setValuesFromHex(string $hex): ?int
     {
         if (!\ctype_xdigit($hex)) {
@@ -378,6 +395,7 @@ protected function setValuesFromHex(string $hex): ?int
         return $variant;
     }
 
+    /** @psalm-return ?positive-int */
     protected function setValuesFromFunction(string $value): ?int
     {
         if (!\preg_match('/^((?:rgb|hsl)a?)\\s*\\(([0-9\\.%,\\s\\/\\-]+)\\)$/i', $value, $match)) {
diff --git a/src/Zval/Representation/MethodDefinitionRepresentation.php b/src/Zval/Representation/MethodDefinitionRepresentation.php
index 6c1ca38bb..bcc5499d7 100644
--- a/src/Zval/Representation/MethodDefinitionRepresentation.php
+++ b/src/Zval/Representation/MethodDefinitionRepresentation.php
@@ -64,7 +64,7 @@ public function __construct(?string $file, ?int $line, ?string $class, ?string $
      */
     public function getDocstringWithoutComments()
     {
-        if (!$this->contents) {
+        if (!\is_string($this->contents) || '' === $this->contents) {
             return null;
         }
 
diff --git a/src/Zval/Representation/Representation.php b/src/Zval/Representation/Representation.php
index c4680c3d1..b47a0ef47 100644
--- a/src/Zval/Representation/Representation.php
+++ b/src/Zval/Representation/Representation.php
@@ -32,6 +32,8 @@ class Representation
     public $label;
     public $implicit_label = false;
     public $hints = [];
+
+    /** @psalm-var null|scalar|\Kint\Zval\Value|\Kint\Zval\Value[] */
     public $contents = [];
 
     protected $name;
diff --git a/src/Zval/Representation/SplFileInfoRepresentation.php b/src/Zval/Representation/SplFileInfoRepresentation.php
index dad9d04cd..b09aea5fa 100644
--- a/src/Zval/Representation/SplFileInfoRepresentation.php
+++ b/src/Zval/Representation/SplFileInfoRepresentation.php
@@ -39,8 +39,11 @@ class SplFileInfoRepresentation extends Representation
     public $realpath = null;
     public $linktarget = null;
     public $size = null;
+    /** @var bool */
     public $is_dir = false;
+    /** @var bool */
     public $is_file = false;
+    /** @var bool */
     public $is_link = false;
     public $owner = null;
     public $group = null;
@@ -72,7 +75,8 @@ public function __construct(SplFileInfo $fileInfo)
             $this->is_link = $fileInfo->isLink();
 
             if ($this->is_link) {
-                $this->linktarget = $fileInfo->getLinkTarget();
+                $lt = $fileInfo->getLinkTarget();
+                $this->linktarget = false === $lt ? null : $lt;
             }
         } catch (RuntimeException $e) {
             if (false === \strpos($e->getMessage(), ' open_basedir ')) {
@@ -150,7 +154,7 @@ public function __construct(SplFileInfo $fileInfo)
         $this->contents = \implode($this->flags).' '.$this->owner.' '.$this->group;
         $this->contents .= ' '.$this->getSize().' '.$this->getMTime().' ';
 
-        if ($this->is_link && $this->linktarget) {
+        if ($this->is_link && null !== $this->linktarget) {
             $this->contents .= $this->path.' -> '.$this->linktarget;
         } elseif (null !== $this->realpath && \strlen($this->realpath) < \strlen($this->path)) {
             $this->contents .= $this->realpath;
@@ -168,6 +172,7 @@ public function getLabel(): string
         return $this->typename;
     }
 
+    /** @psalm-return ?truthy-string */
     public function getSize(): ?string
     {
         if ($this->size) {
diff --git a/src/Zval/TraceFrameValue.php b/src/Zval/TraceFrameValue.php
index bee073bb7..70937789b 100644
--- a/src/Zval/TraceFrameValue.php
+++ b/src/Zval/TraceFrameValue.php
@@ -58,10 +58,10 @@ public function __construct(Value $base, array $raw_frame)
             'args' => null,
         ];
 
-        if ($this->trace['class'] && \method_exists($this->trace['class'], $this->trace['function'])) {
+        if (null !== $this->trace['class'] && \method_exists($this->trace['class'], $this->trace['function'])) {
             $func = new ReflectionMethod($this->trace['class'], $this->trace['function']);
             $this->trace['function'] = new MethodValue($func);
-        } elseif (!$this->trace['class'] && \function_exists($this->trace['function'])) {
+        } elseif (null === $this->trace['class'] && \function_exists($this->trace['function'])) {
             $func = new ReflectionFunction($this->trace['function']);
             $this->trace['function'] = new MethodValue($func);
         }
@@ -91,16 +91,16 @@ public function __construct(Value $base, array $raw_frame)
             $this->addRepresentation(new SourceRepresentation($this->trace['file'], $this->trace['line']));
         }
 
-        if ($this->trace['args']) {
+        if (null !== $this->trace['args']) {
             $args = new Representation('Arguments');
             $args->contents = $this->trace['args'];
             $this->addRepresentation($args);
         }
 
-        if ($this->trace['object']) {
+        if (null !== $this->trace['object']) {
             $callee = new Representation('object');
             $callee->label = 'Callee object ['.$this->trace['object']->classname.']';
-            $callee->contents[] = $this->trace['object'];
+            $callee->contents = [$this->trace['object']];
             $this->addRepresentation($callee);
         }
     }
diff --git a/src/Zval/Value.php b/src/Zval/Value.php
index 37885d97e..4e3bf2279 100644
--- a/src/Zval/Value.php
+++ b/src/Zval/Value.php
@@ -56,6 +56,7 @@ class Value
     public $hints = [];
     public $value;
 
+    /** @var Representation[] */
     protected $representations = [];
 
     public function __construct()
@@ -108,6 +109,7 @@ public function getRepresentation(string $name): ?Representation
         return $this->representations[$name] ?? null;
     }
 
+    /** @psalm-return Representation[] */
     public function getRepresentations(): array
     {
         return $this->representations;
@@ -169,6 +171,7 @@ public function getName(): ?string
         return null;
     }
 
+    /** @psalm-return ?truthy-string */
     public function getOperator(): ?string
     {
         switch ($this->operator) {