diff --git a/src/BigDecimal.php b/src/BigDecimal.php
index 4128a57..e70870d 100644
--- a/src/BigDecimal.php
+++ b/src/BigDecimal.php
@@ -45,6 +45,8 @@ final class BigDecimal extends BigNumber implements \Serializable
     }
 
     /**
+     * Creates a BigDecimal of the given value.
+     *
      * @param BigNumber|number|string $value
      *
      * @return BigDecimal
@@ -57,12 +59,16 @@ final class BigDecimal extends BigNumber implements \Serializable
     }
 
     /**
-     * @param BigInteger|int|string $value An integer representing the unscaled value of the number.
-     * @param int                   $scale The scale of the number, positive or zero.
+     * Creates a BigDecimal from an unscaled value and a scale.
+     *
+     * Example: `(12345, 3)` will result in the BigDecimal `12.345`.
+     *
+     * @param BigNumber|number|string $value The unscaled value. Must be convertible to a BigInteger.
+     * @param int                     $scale The scale of the number, positive or zero.
      *
      * @return BigDecimal
      *
-     * @throws \InvalidArgumentException
+     * @throws \InvalidArgumentException If the scale is negative.
      */
     public static function ofUnscaledValue($value, $scale = 0)
     {
diff --git a/src/BigInteger.php b/src/BigInteger.php
index 6ac485c..e9dadcf 100644
--- a/src/BigInteger.php
+++ b/src/BigInteger.php
@@ -36,6 +36,8 @@ final class BigInteger extends BigNumber implements \Serializable
     }
 
     /**
+     * Creates a BigInteger of the given value.
+     *
      * @param BigNumber|number|string $value
      *
      * @return BigInteger
diff --git a/src/BigNumber.php b/src/BigNumber.php
index 4b9ad52..afa69f1 100644
--- a/src/BigNumber.php
+++ b/src/BigNumber.php
@@ -102,6 +102,8 @@ abstract class BigNumber
     /**
      * Proxy method to access protected constructors from sibling classes.
      *
+     * @internal
+     *
      * @param mixed ...$args The arguments to the constructor.
      *
      * @return static
diff --git a/src/BigRational.php b/src/BigRational.php
index b336e79..8d69e1e 100644
--- a/src/BigRational.php
+++ b/src/BigRational.php
@@ -55,6 +55,8 @@ final class BigRational extends BigNumber implements \Serializable
     }
 
     /**
+     * Creates a BigRational of the given value.
+     *
      * @param BigNumber|number|string $value
      *
      * @return BigRational