diff --git a/src/Cli/Attribute/InvalidArgument.php b/src/Cli/Attribute/InvalidArgument.php
new file mode 100644
index 0000000..5578186
--- /dev/null
+++ b/src/Cli/Attribute/InvalidArgument.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace Bauhaus\Cli\Attribute;
+
+use InvalidArgumentException;
+
+final class InvalidArgument extends InvalidArgumentException
+{
+    public function __construct(string $invalid)
+    {
+        parent::__construct("Invalid cli argument: '$invalid'");
+    }
+}
diff --git a/src/Cli/Attribute/Name.php b/src/Cli/Attribute/Name.php
index a08ed08..18e150d 100644
--- a/src/Cli/Attribute/Name.php
+++ b/src/Cli/Attribute/Name.php
@@ -10,6 +10,7 @@ final class Name
     public function __construct(
         private string $value,
     ) {
+        $this->assertIsValid();
     }
 
     public function equalTo(self $that): bool
@@ -21,4 +22,15 @@ public function __toString(): string
     {
         return $this->value;
     }
+
+    private function assertIsValid(): void
+    {
+        $alphaNumeric = 'A-Za-z0-9';
+        $allowed = "$alphaNumeric-_";
+        $word = "[$alphaNumeric][$allowed]*";
+
+        if (0 === preg_match("/^$word(:$word)*$/", $this->value)) {
+            throw new InvalidArgument($this->value);
+        }
+    }
 }
diff --git a/src/Cli/Command.php b/src/Cli/Command.php
index bc956aa..3b86bfe 100644
--- a/src/Cli/Command.php
+++ b/src/Cli/Command.php
@@ -35,7 +35,7 @@ public function execute(Input $input, Output $output): void
 
     public function match(Input $input): bool
     {
-        return $this->id->equalTo($input->commandId());
+        return $this->id->equalTo($input->commandName());
     }
 
     private function extractEntrypointAttributes(): void
diff --git a/src/Cli/Input.php b/src/Cli/Input.php
index 03cf11b..59e0f07 100644
--- a/src/Cli/Input.php
+++ b/src/Cli/Input.php
@@ -7,7 +7,7 @@
 final class Input
 {
     private array $argv;
-    private Name $commandId;
+    private Name $commandName;
 
     private function __construct(string ...$rawInput)
     {
@@ -25,13 +25,13 @@ public static function fromString(string $string): self
         return new self(...explode(' ', $string));
     }
 
-    public function commandId(): Name
+    public function commandName(): Name
     {
-        return $this->commandId;
+        return $this->commandName;
     }
 
     private function parseInput(): void
     {
-        $this->commandId = new Name($this->argv[1]);
+        $this->commandName = new Name($this->argv[1]);
     }
 }
diff --git a/tests/Cli/Attribute/NameTest.php b/tests/Cli/Attribute/NameTest.php
new file mode 100644
index 0000000..42b26bd
--- /dev/null
+++ b/tests/Cli/Attribute/NameTest.php
@@ -0,0 +1,78 @@
+<?php
+
+namespace Bauhaus\Cli\Attribute;
+
+use PHPUnit\Framework\TestCase;
+
+class NameTest extends TestCase
+{
+    public function invalidNames(): array
+    {
+        return [
+            ['inv lid'],
+            ['inv@lid'],
+            [' invalid'],
+            [''],
+            ['-'],
+            ['invalid:'],
+        ];
+    }
+
+    /**
+     * @test
+     * @dataProvider invalidNames
+     */
+    public function throwExceptionIfNameIsInvalid(string $invalid): void
+    {
+        $this->expectException(InvalidArgument::class);
+        $this->expectExceptionMessage("Invalid cli argument: '$invalid'");
+
+        new Name($invalid);
+    }
+
+    public function validNames(): array
+    {
+        return [
+            ['valid'],
+            ['val:id'],
+            ['va:aa:lid'],
+            ['v:aa:lid'],
+            ['v:a:lid'],
+            ['val_id'],
+            ['val-id'],
+            ['val-i_d'],
+            ['val_-id'],
+        ];
+    }
+
+    /**
+     * @test
+     * @dataProvider validNames
+     */
+    public function convertToString(string $str): void
+    {
+        $name = new Name($str);
+
+        $this->assertEquals($str, (string) $name);
+    }
+
+    /**
+     * @test
+     */
+    public function returnTrueIfTwoNameAreEqual(): void
+    {
+        $name = new Name('something');
+
+        $this->assertTrue($name->equalTo(new Name('something')));
+    }
+
+    /**
+     * @test
+     */
+    public function returnFalseIfTwoNameAreNotEqual(): void
+    {
+        $name = new Name('something');
+
+        $this->assertFalse($name->equalTo(new Name('anotherThing')));
+    }
+}
diff --git a/tests/Cli/InputTest.php b/tests/Cli/InputTest.php
index f9aff39..ca5e3c0 100644
--- a/tests/Cli/InputTest.php
+++ b/tests/Cli/InputTest.php
@@ -15,7 +15,7 @@ public function determineCommandIdFromArgv(): void
         $expected = new Name('command-id');
 
         $input = Input::fromArgv('./bin/console', 'command-id');
-        $commandId = $input->commandId();
+        $commandId = $input->commandName();
 
         $this->assertEquals($expected, $commandId);
     }