diff --git a/core/src/main/java/cc/carm/lib/configuration/source/ConfigurationFactory.java b/core/src/main/java/cc/carm/lib/configuration/source/ConfigurationFactory.java
index 85d466e..41adb62 100644
--- a/core/src/main/java/cc/carm/lib/configuration/source/ConfigurationFactory.java
+++ b/core/src/main/java/cc/carm/lib/configuration/source/ConfigurationFactory.java
@@ -20,6 +20,13 @@ import java.util.function.Consumer;
 import java.util.function.Function;
 import java.util.function.Supplier;
 
+/**
+ * ConfigurationFactory, used to create configuration holder.
+ *
+ * @param <SOURCE> The {@link ConfigureSource} type
+ * @param <HOLDER> The {@link ConfigurationHolder} type.
+ * @param <SELF>   Self builder, for further implement support.
+ */
 public abstract class ConfigurationFactory<
         SOURCE extends ConfigureSource<?, ?, SOURCE>,
         HOLDER extends ConfigurationHolder<SOURCE>,
@@ -139,18 +146,39 @@ public abstract class ConfigurationFactory<
         return self();
     }
 
+    /**
+     * Supply the base path generator for this configuration holder
+     *
+     * @param generator {@link  PathGenerator}
+     * @return this
+     */
     public SELF pathGenerator(PathGenerator generator) {
         return initializer(loader -> {
             loader.pathGenerator(generator);
         });
     }
 
+    /**
+     * Register a new annotation for metadata to the configuration loader
+     *
+     * @param annotation The {@link Annotation}
+     * @param metadata   The {@link ConfigurationMetadata} type
+     * @param extractor  The {@link Function} to extract the metadata from the annotation
+     * @param <M>        The metadata type
+     * @param <A>        The annotation type
+     * @return this
+     */
     public <M, A extends Annotation> SELF metaAnnotation(@NotNull Class<A> annotation,
                                                          @NotNull ConfigurationMetadata<M> metadata,
                                                          @NotNull Function<A, M> extractor) {
         return initializer(loader -> loader.registerAnnotation(annotation, metadata, extractor));
     }
 
+    /**
+     * Build the configuration holder.
+     *
+     * @return The configuration holder
+     */
     public abstract @NotNull HOLDER build();
 
 }
diff --git a/core/src/main/java/cc/carm/lib/configuration/source/loader/PathGenerator.java b/core/src/main/java/cc/carm/lib/configuration/source/loader/PathGenerator.java
index df9701e..665f43a 100644
--- a/core/src/main/java/cc/carm/lib/configuration/source/loader/PathGenerator.java
+++ b/core/src/main/java/cc/carm/lib/configuration/source/loader/PathGenerator.java
@@ -9,6 +9,12 @@ import org.jetbrains.annotations.Nullable;
 import java.lang.reflect.Field;
 import java.util.function.UnaryOperator;
 
+/**
+ * Path generator for configuration.
+ * <p>
+ * Path generator is a utility class that helps to generate the path of the configuration.
+ * It can be used to generate the path of the field or class.
+ */
 public class PathGenerator {
 
     public static PathGenerator of() {
diff --git a/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSection.java b/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSection.java
index b1de0a1..00955a9 100644
--- a/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSection.java
+++ b/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSection.java
@@ -11,56 +11,199 @@ import java.util.function.Function;
 import java.util.function.Supplier;
 import java.util.stream.Stream;
 
+/**
+ * Represents a section of a configuration.
+ *
+ * @author Carm
+ * @since 4.0.0
+ */
 public interface ConfigureSection {
 
+    /**
+     * Gets the parent section of this section.
+     * <p>
+     * For root sections, this will return null.
+     *
+     * @return Parent section, or null if this is a root section.
+     */
+    @Contract(pure = true)
     @Nullable ConfigureSection parent();
 
+    /**
+     * Gets a set containing all keys in this section.
+     * <p>
+     * If deep is set to true, then this will contain all the keys within any
+     * child {@link ConfigureSection}s (and their children paths).
+     * <p>
+     * If deep is set to false, then this will contain only the keys of any
+     * direct children, and not their own children.
+     *
+     * @param deep Whether to get a deep list.
+     * @return Set of keys contained within this Section.
+     */
     @NotNull
     @UnmodifiableView
     default Set<String> getKeys(boolean deep) {
         return getValues(deep).keySet();
     }
 
+    /**
+     * Gets a set containing all values in this section.
+     * <p>
+     * If deep is set to true, then this will contain all the keys within any
+     * child {@link ConfigureSection}s (and their children paths).
+     * <p>
+     * If deep is set to false, then this will contain only the keys of any
+     * direct children, and not their own children.
+     *
+     * @param deep Whether to get a deep list.
+     * @return Map of data values contained within this Section.
+     */
     @NotNull
     @UnmodifiableView
     Map<String, Object> getValues(boolean deep);
 
+    /**
+     * Sets the value at the given path.
+     * <p>
+     * Null values will be kept, if you want to remove a value use {@link #remove(String)}
+     * Path separator depends on holder's
+     * {@link cc.carm.lib.configuration.source.option.StandardOptions#PATH_SEPARATOR}
+     *
+     * @param path  The path to set the value at.
+     * @param value The value to set.
+     */
     void set(@NotNull String path, @Nullable Object value);
 
+    /**
+     * Removes the value at the given path.
+     * <p>
+     * Path separator depends on holder's
+     * {@link cc.carm.lib.configuration.source.option.StandardOptions#PATH_SEPARATOR}
+     *
+     * @param path The path to remove the value at.
+     */
+    void remove(@NotNull String path);
+
+    /**
+     * Check if the value of given path is present.
+     * <p>
+     * Path separator depends on holder's
+     * {@link cc.carm.lib.configuration.source.option.StandardOptions#PATH_SEPARATOR}
+     *
+     * @param path The path to check.
+     * @return True if the value is present, false otherwise.
+     */
     boolean contains(@NotNull String path);
 
+    /**
+     * Predicate the value of given path is specific type.
+     *
+     * @param path      The path to check.
+     * @param typeClass The type's class
+     * @param <T>       The type to check.
+     * @return True if the value is present and is the correct type, false otherwise.
+     */
     default <T> boolean isType(@NotNull String path, @NotNull Class<T> typeClass) {
         return typeClass.isInstance(get(path));
     }
 
+    /**
+     * Predicate the value of given path is a  {@link List}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a list, false otherwise.
+     */
     default boolean isList(@NotNull String path) {
         return isType(path, List.class);
     }
 
+    /**
+     * Get the value as a {@link List} from the specified path.
+     *
+     * @param path The path to get the  {@link List}.
+     * @return The list if the path exists and is a list, otherwise null.
+     */
     @Nullable List<?> getList(@NotNull String path);
 
+    /**
+     * Predicate the value of given path is a {@link ConfigureSection}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a section, false otherwise.
+     */
     default boolean isSection(@NotNull String path) {
         return isType(path, ConfigureSection.class);
     }
 
+    /**
+     * Get the value as a {@link ConfigureSection} from the specified path.
+     *
+     * @param path The path to get the section.
+     * @return The section if the path exists and is a section, otherwise null.
+     */
     @Nullable
     ConfigureSection getSection(@NotNull String path);
 
+    /**
+     * Get the origin value of the path.
+     *
+     * @param path The path to get the value from.
+     * @return The value at the path, or null if not found.
+     */
     @Nullable Object get(@NotNull String path);
 
-    default @Nullable <T> T get(@NotNull String path, @NotNull Class<T> clazz) {
-        return get(path, null, clazz);
+    /**
+     * Get the value of the path for specific type,
+     * if the path does not exist, return null.
+     *
+     * @param path The path to get the value from.
+     * @param type The type class of the value
+     * @param <T>  The type of the value
+     * @return The value at the path, or the default value if not found.
+     */
+    default @Nullable <T> T get(@NotNull String path, @NotNull Class<T> type) {
+        return get(path, null, type);
     }
 
-    default @Nullable <T> T get(@NotNull String path, @NotNull DataFunction<Object, T> parser) {
+    /**
+     * Get the value of the path using a parser function,
+     * if the path does not exist, return NULL.
+     *
+     * @param path   The path to get the value from.
+     * @param parser The function to parse the value
+     * @param <T>    The type of the value
+     * @return The value at the path, or null if not found.
+     */
+    default @Nullable <T> T get(@NotNull String path, @NotNull DataFunction<@Nullable Object, T> parser) {
         return get(path, null, parser);
     }
 
+    /**
+     * Get the value of the path for specific type,
+     * if the path does not exist, return the default value.
+     *
+     * @param path     The path to get the value from.
+     * @param defaults The default value to return if the path does not exist.
+     * @param clazz    The type class of the value
+     * @param <T>      The type of the value
+     * @return The value at the path, or the default value if not found.
+     */
     @Contract("_,!null,_->!null")
-    default @Nullable <T> T get(@NotNull String path, @Nullable T defaultValue, @NotNull Class<T> clazz) {
-        return get(path, defaultValue, DataFunction.castObject(clazz));
+    default @Nullable <T> T get(@NotNull String path, @Nullable T defaults, @NotNull Class<T> clazz) {
+        return get(path, defaults, DataFunction.castObject(clazz));
     }
 
+    /**
+     * Get the value of the path using a parser function,
+     * if the path does not exist, return the default value.
+     *
+     * @param path         The path to get the value from.
+     * @param defaultValue The default value to return if the path does not exist.
+     * @param parser       The function to parse the value
+     * @param <T>          The type of the value
+     * @return The value at the path, or the default value if not found.
+     */
     @Contract("_,!null,_->!null")
     default @Nullable <T> T get(@NotNull String path, @Nullable T defaultValue,
                                 @NotNull DataFunction<Object, T> parser) {
@@ -75,125 +218,290 @@ public interface ConfigureSection {
         return defaultValue;
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link Boolean}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a boolean, false otherwise.
+     */
     default boolean isBoolean(@NotNull String path) {
         return isType(path, Boolean.class);
     }
 
+    /**
+     * Get the value as a {@link Boolean} from the specified path.
+     *
+     * @param path The path to get the boolean.
+     * @return The boolean if the path exists and is a boolean, otherwise false.
+     */
     default boolean getBoolean(@NotNull String path) {
         return getBoolean(path, false);
     }
 
+    /**
+     * Get the value as a {@link Boolean} from the specified path.
+     *
+     * @param path The path to get the boolean.
+     * @param def  The default value to return if the path does not exist.
+     * @return The boolean if the path exists and is a boolean, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Boolean getBoolean(@NotNull String path, @Nullable Boolean def) {
         return get(path, def, DataFunction.booleanValue());
     }
 
+    /**
+     * Predicate the value of given path is a {@link Byte}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a byte, false otherwise.
+     */
     default @Nullable Boolean isByte(@NotNull String path) {
         return isType(path, Byte.class);
     }
 
+    /**
+     * Get the value as a {@link Byte} from the specified path.
+     *
+     * @param path The path to get the byte.
+     * @return The byte if the path exists and is a byte, otherwise 0.
+     */
     default @Nullable Byte getByte(@NotNull String path) {
         return getByte(path, (byte) 0);
     }
 
+    /**
+     * Get the value as a {@link Byte} from the specified path.
+     *
+     * @param path The path to get the byte.
+     * @param def  The default value to return if the path does not exist.
+     * @return The byte if the path exists and is a byte, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Byte getByte(@NotNull String path, @Nullable Byte def) {
         return get(path, def, DataFunction.byteValue());
     }
 
+    /**
+     * Predicate the value of given path is a {@link Short}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a short, false otherwise.
+     */
     default boolean isShort(@NotNull String path) {
         return isType(path, Short.class);
     }
 
+    /**
+     * Get the value as a {@link Short} from the specified path.
+     *
+     * @param path The path to get the short.
+     * @return The short if the path exists and is a short, otherwise 0.
+     */
     default @Nullable Short getShort(@NotNull String path) {
         return getShort(path, (short) 0);
     }
 
+    /**
+     * Get the value as a {@link Short} from the specified path.
+     *
+     * @param path The path to get the short.
+     * @param def  The default value to return if the path does not exist.
+     * @return The short if the path exists and is a short, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Short getShort(@NotNull String path, @Nullable Short def) {
         return get(path, def, DataFunction.shortValue());
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link Integer}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a int, false otherwise.
+     */
     default boolean isInt(@NotNull String path) {
         return isType(path, Integer.class);
     }
 
+    /**
+     * Get the value as a {@link Integer} from the specified path.
+     *
+     * @param path The path to get the int.
+     * @return The int if the path exists and is a int, otherwise 0.
+     */
     default @Nullable Integer getInt(@NotNull String path) {
         return getInt(path, 0);
     }
 
+    /**
+     * Get the value as a {@link Integer} from the specified path.
+     *
+     * @param path The path to get the int.
+     * @param def  The default value to return if the path does not exist.
+     * @return The int if the path exists and is a int, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Integer getInt(@NotNull String path, @Nullable Integer def) {
         return get(path, def, DataFunction.intValue());
     }
 
 
+    /**
+     * Predicate the value of given path is a {@link Long}.F
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a long, false otherwise.
+     */
     default boolean isLong(@NotNull String path) {
         return isType(path, Long.class);
     }
 
+    /**
+     * Get the value as a {@link Long} from the specified path.
+     *
+     * @param path The path to get the long.
+     * @return The long if the path exists and is a long, otherwise 0.
+     */
     default @Nullable Long getLong(@NotNull String path) {
         return getLong(path, 0L);
     }
 
+    /**
+     * Get the value as a {@link Long} from the specified path.
+     *
+     * @param path The path to get the long.
+     * @param def  The default value to return if the path does not exist.
+     * @return The long if the path exists and is a long, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Long getLong(@NotNull String path, @Nullable Long def) {
         return get(path, def, DataFunction.longValue());
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link Float}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a float, false otherwise.
+     */
     default boolean isFloat(@NotNull String path) {
         return isType(path, Float.class);
     }
 
+    /**
+     * Get the value as a {@link Float} from the specified path.
+     *
+     * @param path The path to get the float.
+     * @return The float if the path exists and is a float, otherwise 0.
+     */
     default @Nullable Float getFloat(@NotNull String path) {
         return getFloat(path, 0.0F);
     }
 
+    /**
+     * Get the value as a {@link Float} from the specified path.
+     *
+     * @param path The path to get the float.
+     * @param def  The default value to return if the path does not exist.
+     * @return The float if the path exists and is a float, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Float getFloat(@NotNull String path, @Nullable Float def) {
         return get(path, def, DataFunction.floatValue());
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link Double}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a double, false otherwise.
+     */
     default boolean isDouble(@NotNull String path) {
         return isType(path, Double.class);
     }
 
+    /**
+     * Get the value as a {@link Double} from the specified path.
+     *
+     * @param path The path to get the double.
+     * @return The double if the path exists and is a double, otherwise 0.
+     */
     default @Nullable Double getDouble(@NotNull String path) {
         return getDouble(path, 0.0D);
     }
 
+    /**
+     * Get the value as a {@link Double} from the specified path.
+     *
+     * @param path The path to get the double.
+     * @param def  The default value to return if the path does not exist.
+     * @return The double if the path exists and is a double, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Double getDouble(@NotNull String path, @Nullable Double def) {
         return get(path, def, DataFunction.doubleValue());
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link Character}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a char, false otherwise.
+     */
     default boolean isChar(@NotNull String path) {
         return isType(path, Boolean.class);
     }
 
+    /**
+     * Get the value as a {@link Character} from the specified path.
+     *
+     * @param path The path to get the char.
+     * @return The char if the path exists and is a char, otherwise null.
+     */
     default @Nullable Character getChar(@NotNull String path) {
         return getChar(path, null);
     }
 
+    /**
+     * Get the value as a {@link Character} from the specified path.
+     *
+     * @param path The path to get the char.
+     * @param def  The default value to return if the path does not exist.
+     * @return The char if the path exists and is a char, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable Character getChar(@NotNull String path, @Nullable Character def) {
         return get(path, def, Character.class);
     }
 
-
+    /**
+     * Predicate the value of given path is a {@link String}.
+     *
+     * @param path The path to check.
+     * @return True if the value is present and is a string, false otherwise.
+     */
     default boolean isString(@NotNull String path) {
         return isType(path, String.class);
     }
 
+    /**
+     * Get the value as a {@link String} from the specified path.
+     *
+     * @param path The path to get the string.
+     * @return The string if the path exists and is a string, otherwise null.
+     */
     default @Nullable String getString(@NotNull String path) {
         return getString(path, null);
     }
 
+    /**
+     * Get the value as a {@link String} from the specified path.
+     *
+     * @param path The path to get the string.
+     * @param def  The default value to return if the path does not exist.
+     * @return The string if the path exists and is a string, otherwise the default value.
+     */
     @Contract("_, !null -> !null")
     default @Nullable String getString(@NotNull String path, @Nullable String def) {
         return get(path, def, String.class);
@@ -291,17 +599,41 @@ public interface ConfigureSection {
         return getList(path, DataFunction.castObject(Character.class));
     }
 
+    /**
+     * Get the specific type of collection from the section.
+     *
+     * @param path        The path to get the collection from
+     * @param constructor The constructor of the collection
+     * @param parser      The function to parse the values
+     * @param <T>         The type of the values
+     * @param <C>         The type of the collection
+     * @return The collection of values
+     */
     default <T, C extends Collection<T>> @NotNull C getCollection(@NotNull String path,
                                                                   @NotNull Supplier<C> constructor,
                                                                   @NotNull DataFunction<Object, T> parser) {
         return parseCollection(getList(path), constructor, parser);
     }
 
+    /**
+     * Get the specific type of steam from the section.
+     *
+     * @param path The path to get the stream from
+     * @return The stream of values
+     */
     default @NotNull Stream<?> stream(@NotNull String path) {
         List<?> values = getList(path);
         return values == null ? Stream.empty() : values.stream();
     }
 
+    /**
+     * Get the specific type of steam from the section.
+     *
+     * @param path   The path to get the stream from
+     * @param parser The function to parse the values
+     * @param <T>    The type of the values
+     * @return The stream of values
+     */
     default <T> @NotNull Stream<T> stream(@NotNull String path, @NotNull Function<Object, T> parser) {
         return stream(path).map(parser);
     }
diff --git a/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSource.java b/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSource.java
index 6edf142..7322bc1 100644
--- a/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSource.java
+++ b/core/src/main/java/cc/carm/lib/configuration/source/section/ConfigureSource.java
@@ -10,6 +10,14 @@ import org.jetbrains.annotations.Nullable;
 import java.util.List;
 import java.util.Map;
 
+/**
+ * ConfigureSource represents the source of configuration,
+ * which can be a file, a database, or any other source.
+ *
+ * @param <SECTION>  The type of the root section.
+ * @param <ORIGINAL> The original configuration object.
+ * @param <SELF>     The type of the source itself, for further implement support.
+ */
 public abstract class ConfigureSource<
         SECTION extends ConfigureSection, ORIGINAL,
         SELF extends ConfigureSource<SECTION, ORIGINAL, SELF>>
diff --git a/features/commentable/src/main/java/cc/carm/lib/configuration/annotation/InlineComments.java b/features/commentable/src/main/java/cc/carm/lib/configuration/annotation/InlineComments.java
index a162961..f76089d 100644
--- a/features/commentable/src/main/java/cc/carm/lib/configuration/annotation/InlineComments.java
+++ b/features/commentable/src/main/java/cc/carm/lib/configuration/annotation/InlineComments.java
@@ -9,7 +9,12 @@ import java.lang.annotation.Target;
 @Retention(RetentionPolicy.RUNTIME)
 public @interface InlineComments {
 
-
+    /**
+     * Multiple inline comments support.
+     *
+     * @return inline comment contents.
+     * @see InlineComment
+     */
     InlineComment[] value();
 
 }
diff --git a/features/section/src/main/java/cc/carm/lib/configuration/source/section/MemorySection.java b/features/section/src/main/java/cc/carm/lib/configuration/source/section/MemorySection.java
index 10ba244..b29fb4f 100644
--- a/features/section/src/main/java/cc/carm/lib/configuration/source/section/MemorySection.java
+++ b/features/section/src/main/java/cc/carm/lib/configuration/source/section/MemorySection.java
@@ -88,6 +88,16 @@ public class MemorySection implements ConfigureSection {
         }
     }
 
+    @Override
+    public void remove(@NotNull String path) {
+        MemorySection section = getSectionFor(path);
+        if (section != this) {
+            section.remove(childPath(path));
+        } else {
+            this.data.remove(path);
+        }
+    }
+
     @Override
     public boolean contains(@NotNull String path) {
         return get(path) != null;