diff --git a/src/main/java/ru/lionarius/CalculationThread.java b/src/main/java/ru/lionarius/CalculationThread.java
index 248d316..23538c5 100644
--- a/src/main/java/ru/lionarius/CalculationThread.java
+++ b/src/main/java/ru/lionarius/CalculationThread.java
@@ -2,14 +2,56 @@ package ru.lionarius;
 
 import java.util.function.Function;
 
+/**
+ * The {@code CalculationThread} class represents a thread that performs
+ * numerical integration over a specific interval using a given function.
+ * It utilizes the {@link IntegralCalculator} to compute the integral for
+ * the specified bounds of the function.
+ *
+ * <p>This class extends {@code Thread} and overrides the {@code run} method
+ * to calculate the integral when the thread starts running.</p>
+ *
+ * <p>Once the calculation is complete, the result can be retrieved using
+ * the {@link #getResult()} method.</p>
+ *
+ * @see IntegralCalculator
+ */
 public class CalculationThread extends Thread {
+
+    /**
+     * The calculator used to perform the integration.
+     */
     private final IntegralCalculator calculator;
+
+    /**
+     * The function to be integrated.
+     */
     private final Function<Double, Double> function;
+
+    /**
+     * The lower bound of the integration interval.
+     */
     private final double lowerBound;
+
+    /**
+     * The upper bound of the integration interval.
+     */
     private final double upperBound;
-    
+
+    /**
+     * The result of the integration.
+     */
     private double result;
-    
+
+    /**
+     * Constructs a new {@code CalculationThread} with the specified calculator,
+     * function, and integration bounds.
+     *
+     * @param calculator the {@link IntegralCalculator} used to compute the integral
+     * @param function   the function to integrate, represented as a {@link Function}
+     * @param lowerBound the lower bound of the integration interval
+     * @param upperBound the upper bound of the integration interval
+     */
     public CalculationThread(IntegralCalculator calculator, Function<Double, Double> function, double lowerBound, double upperBound) {
         this.calculator = calculator;
         this.function = function;
@@ -17,11 +59,20 @@ public class CalculationThread extends Thread {
         this.upperBound = upperBound;
     }
     
+    /**
+     * Calculates the integral of the specified function over the given interval.
+     * This method is executed when the thread is started.
+     */
     @Override
     public void run() {
         this.result = this.calculator.calculate(this.function, this.lowerBound, this.upperBound);
     }
-    
+
+    /**
+     * Returns the result of the integration after the thread completes execution.
+     *
+     * @return the computed result of the integral
+     */
     public double getResult() {
         return this.result;
     }
diff --git a/src/main/java/ru/lionarius/IntegralCalculator.java b/src/main/java/ru/lionarius/IntegralCalculator.java
index 282d4b9..b71babf 100644
--- a/src/main/java/ru/lionarius/IntegralCalculator.java
+++ b/src/main/java/ru/lionarius/IntegralCalculator.java
@@ -71,7 +71,7 @@ public class IntegralCalculator {
         if (function == null)
             throw new NullPointerException("function cannot be null");
 
-        if (lowerBound == upperBound) { 
+        if (lowerBound == upperBound) {
             this.callProgressCallback(0, 1);
             this.callProgressCallback(1, 1);
 
@@ -94,9 +94,9 @@ public class IntegralCalculator {
 
         var sum = (function.apply(lowerBound) + function.apply(upperBound)) / 2;
         for (var i = 1L; i < n; i++) {
-            if (Thread.interrupted())
+            if (Thread.currentThread().isInterrupted())
                 break;
-            
+
             sum += function.apply(lowerBound + h * i);
 
             this.callProgressCallback(i, n);
diff --git a/src/main/java/ru/lionarius/Main.java b/src/main/java/ru/lionarius/Main.java
index 88c62ab..929cd58 100644
--- a/src/main/java/ru/lionarius/Main.java
+++ b/src/main/java/ru/lionarius/Main.java
@@ -29,7 +29,7 @@ public class Main {
             var command = input.split(" ");
 
             if (command.length == 0) {
-                System.out.println("No command entered.");
+                System.out.println("No command entered");
                 continue;
             }
 
@@ -60,9 +60,10 @@ public class Main {
      */
     private static void handleStartCommand(String[] command, Function<Double, Double> function, double lowerBound, double upperBound) {
         if (command.length < 2) {
-            System.out.println("Usage: start <accuracy>");
+            System.out.println("Usage: start <e>");
             return;
         }
+
         double accuracy = Double.parseDouble(command[1]);
         var thread = new CalculationThread(new IntegralCalculator(accuracy), function, lowerBound, upperBound);
         int id = currentId++;
@@ -79,9 +80,10 @@ public class Main {
      */
     private static void handleStopCommand(String[] command) {
         if (command.length < 2) {
-            System.out.println("Usage: stop <threadId>");
+            System.out.println("Usage: stop <n>");
             return;
         }
+
         int id = Integer.parseInt(command[1]);
         var thread = threads.remove(id);
         if (thread == null) {
@@ -100,15 +102,17 @@ public class Main {
      */
     private static void handleAwaitCommand(String[] command) {
         if (command.length < 2) {
-            System.out.println("Usage: await <threadId>");
+            System.out.println("Usage: await <n>");
             return;
         }
+
         int id = Integer.parseInt(command[1]);
         var thread = threads.remove(id);
         if (thread == null) {
             System.out.println("Thread " + id + " not found");
             return;
         }
+
         try {
             thread.join();
             System.out.println("Result: " + thread.getResult());