diff --git a/tests/ErrTest.php b/tests/ErrTest.php
index 335ceb5..b919ee0 100644
--- a/tests/ErrTest.php
+++ b/tests/ErrTest.php
@@ -59,15 +59,6 @@ public function unwrap_throws_exception(): void
         $err->unwrap();
     }
 
-    #[Test]
-    public function expect_throws_withGivenMessage(): void
-    {
-        $err = new Err('error');
-        $this->expectException(\LogicException::class);
-        $this->expectExceptionMessage('config file should be readable');
-        $err->expect('config file should be readable');
-    }
-
     #[Test]
     public function expectErr_returns_error_value(): void
     {
@@ -102,18 +93,6 @@ public function unwrap_withArrayError_describesType(): void
         $err->unwrap();
     }
 
-    #[Test]
-    public function unwrapException_remainsCatchableAsLogicException(): void
-    {
-        $err = new Err('error');
-
-        try {
-            $err->unwrap();
-        } catch (\LogicException $e) {
-            $this->assertInstanceOf(UnwrapException::class, $e);
-        }
-    }
-
     #[Test]
     public function unwrap_withThrowingStringableError_stillThrowsUnwrapException(): void
     {
@@ -178,29 +157,6 @@ public function unwrapErr_returns_error_value(): void
         $this->assertSame('error message', $err->unwrapErr());
     }
 
-    #[Test]
-    public function unwrapErr_withIntValue_returns_int(): void
-    {
-        $err = new Err(404);
-        $this->assertSame(404, $err->unwrapErr());
-    }
-
-    #[Test]
-    public function unwrapErr_withArrayValue_returns_array(): void
-    {
-        $error = ['code' => 500, 'message' => 'Internal Server Error'];
-        $err = new Err($error);
-        $this->assertSame($error, $err->unwrapErr());
-    }
-
-    #[Test]
-    public function unwrapErr_withObjectValue_returns_object(): void
-    {
-        $error = new \Exception('Test exception');
-        $err = new Err($error);
-        $this->assertSame($error, $err->unwrapErr());
-    }
-
     #[Test]
     public function unwrapOr_returns_default(): void
     {
@@ -208,14 +164,6 @@ public function unwrapOr_returns_default(): void
         $this->assertSame(42, $err->unwrapOr(42));
     }
 
-    #[Test]
-    public function unwrapOr_withDifferentTypes_returns_default(): void
-    {
-        $err = new Err('error');
-        $this->assertSame('default', $err->unwrapOr('default'));
-        $this->assertSame(['default'], $err->unwrapOr(['default']));
-    }
-
     #[Test]
     public function unwrapOrElse_calls_function(): void
     {
@@ -250,15 +198,6 @@ public function mapErr_applies_function_to_error(): void
         $this->assertSame('ERROR', $mapped->unwrapErr());
     }
 
-    #[Test]
-    public function mapErr_withTypeChange_transforms_type(): void
-    {
-        $err = new Err(404);
-        $mapped = $err->mapErr(fn ($code) => "Error code: $code");
-        $this->assertInstanceOf(Err::class, $mapped);
-        $this->assertSame('Error code: 404', $mapped->unwrapErr());
-    }
-
     #[Test]
     public function inspect_does_not_call_function(): void
     {
@@ -328,16 +267,6 @@ public function andThen_returns_self(): void
         $this->assertSame('error', $result->unwrapErr());
     }
 
-    #[Test]
-    public function andThen_withDifferentErrorType_keeps_original_error(): void
-    {
-        $err = new Err(self::asString('validation failed'));
-        $result = $err->andThen(fn ($x) => new Err(new \DomainException('unreachable')));
-
-        $this->assertSame($err, $result);
-        $this->assertSame('validation failed', $result->unwrapErr());
-    }
-
     #[Test]
     public function or_withAnotherErr_returns_second_err(): void
     {
@@ -378,17 +307,6 @@ public function match_calls_err_function(): void
         $this->assertSame('Error: error', $result);
     }
 
-    #[Test]
-    public function match_withDifferentReturnTypes_returns_err_branch(): void
-    {
-        $err = new Err(404);
-        $result = $err->match(
-            fn ($value) => ['status' => 'ok', 'data' => $value],
-            fn ($error) => ['status' => 'error', 'code' => $error],
-        );
-        $this->assertSame(['status' => 'error', 'code' => 404], $result);
-    }
-
     #[Test]
     public function match_supportsNamedArguments(): void
     {
@@ -425,22 +343,6 @@ public function err_withFalseValue_handles_false(): void
         $this->assertTrue($err->isErr());
     }
 
-    #[Test]
-    public function err_withZeroValue_handles_zero(): void
-    {
-        $err = new Err(0);
-        $this->assertSame(0, $err->unwrapErr());
-        $this->assertTrue($err->isErr());
-    }
-
-    #[Test]
-    public function err_withEmptyString_handles_empty_string(): void
-    {
-        $err = new Err('');
-        $this->assertSame('', $err->unwrapErr());
-        $this->assertTrue($err->isErr());
-    }
-
     #[Test]
     public function chainingOperations_applies_transformations(): void
     {
@@ -454,19 +356,6 @@ public function chainingOperations_applies_transformations(): void
         $this->assertSame('Final: [INITIAL ERROR]', $result->unwrapErr());
     }
 
-    #[Test]
-    public function exceptionAsErrorValue_handles_exception(): void
-    {
-        $exception = new \RuntimeException('Something went wrong');
-        $err = new Err($exception);
-
-        $this->assertTrue($err->isErr());
-        $this->assertSame($exception, $err->unwrapErr());
-
-        $handled = $err->mapErr(fn ($e) => $e->getMessage());
-        $this->assertSame('Something went wrong', $handled->unwrapErr());
-    }
-
     /**
      * リテラル型を int に広げます（共変テンプレートは定数型を保持するため）.
      */
diff --git a/tests/OkTest.php b/tests/OkTest.php
index ba2bcdb..3824549 100644
--- a/tests/OkTest.php
+++ b/tests/OkTest.php
@@ -57,30 +57,6 @@ public function unwrap_returns_value(): void
         $this->assertSame(42, $ok->unwrap());
     }
 
-    #[Test]
-    public function unwrap_withStringValue_returns_string(): void
-    {
-        $ok = new Ok('hello');
-        $this->assertSame('hello', $ok->unwrap());
-    }
-
-    #[Test]
-    public function unwrap_withArrayValue_returns_array(): void
-    {
-        $value = ['foo' => 'bar'];
-        $ok = new Ok($value);
-        $this->assertSame($value, $ok->unwrap());
-    }
-
-    #[Test]
-    public function unwrap_withObjectValue_returns_object(): void
-    {
-        $value = new \stdClass();
-        $value->foo = 'bar';
-        $ok = new Ok($value);
-        $this->assertSame($value, $ok->unwrap());
-    }
-
     #[Test]
     public function unwrapErr_throws_exception(): void
     {
@@ -97,15 +73,6 @@ public function expect_returns_value(): void
         $this->assertSame(42, $ok->expect('should have a value'));
     }
 
-    #[Test]
-    public function expectErr_throws_withGivenMessage(): void
-    {
-        $ok = new Ok(42);
-        $this->expectException(\LogicException::class);
-        $this->expectExceptionMessage('should have an error');
-        $ok->expectErr('should have an error');
-    }
-
     #[Test]
     public function unwrapErr_throwsUnwrapException_withValueInMessage(): void
     {
@@ -163,15 +130,6 @@ public function map_applies_function_to_value(): void
         $this->assertSame(20, $mapped->unwrap());
     }
 
-    #[Test]
-    public function map_withTypeChange_transforms_type(): void
-    {
-        $ok = new Ok(42);
-        $mapped = $ok->map(fn ($x) => "Value is: $x");
-        $this->assertInstanceOf(Ok::class, $mapped);
-        $this->assertSame('Value is: 42', $mapped->unwrap());
-    }
-
     #[Test]
     public function mapErr_does_nothing(): void
     {
@@ -240,32 +198,6 @@ public function andThen_applies_function(): void
         $this->assertSame(20, $result->unwrap());
     }
 
-    #[Test]
-    public function andThen_withDifferentErrorType_chains_results(): void
-    {
-        $ok = new Ok(self::asInt(10));
-        $result = $ok->andThen(
-            fn ($x) => $x > 5 ? new Ok("value: $x") : new Err(new \DomainException('too small')),
-        );
-
-        $this->assertInstanceOf(Ok::class, $result);
-        $this->assertSame('value: 10', $result->unwrap());
-    }
-
-    #[Test]
-    public function andThen_withDifferentErrorType_returns_new_err(): void
-    {
-        $ok = new Ok(self::asInt(3));
-        $result = $ok->andThen(
-            fn ($x) => $x > 5 ? new Ok("value: $x") : new Err(new \DomainException('too small')),
-        );
-
-        $this->assertInstanceOf(Err::class, $result);
-        $error = $result->unwrapErr();
-        $this->assertInstanceOf(\DomainException::class, $error);
-        $this->assertSame('too small', $error->getMessage());
-    }
-
     #[Test]
     public function or_returns_self(): void
     {
@@ -306,17 +238,6 @@ public function match_calls_ok_function(): void
         $this->assertSame('Success: 42', $result);
     }
 
-    #[Test]
-    public function match_withDifferentReturnTypes_returns_ok_branch(): void
-    {
-        $ok = new Ok('hello');
-        $result = $ok->match(
-            fn ($value) => \strlen($value),
-            fn ($error) => -1,
-        );
-        $this->assertSame(5, $result);
-    }
-
     #[Test]
     public function match_supportsNamedArguments(): void
     {
@@ -353,22 +274,6 @@ public function ok_withFalseValue_handles_false(): void
         $this->assertTrue($ok->isOk());
     }
 
-    #[Test]
-    public function ok_withZeroValue_handles_zero(): void
-    {
-        $ok = new Ok(0);
-        $this->assertSame(0, $ok->unwrap());
-        $this->assertTrue($ok->isOk());
-    }
-
-    #[Test]
-    public function ok_withEmptyString_handles_empty_string(): void
-    {
-        $ok = new Ok('');
-        $this->assertSame('', $ok->unwrap());
-        $this->assertTrue($ok->isOk());
-    }
-
     #[Test]
     public function chainingOperations_applies_transformations(): void
     {