diff --git a/tests/test_integration.py b/tests/test_integration.py
new file mode 100644
index 0000000..a4b9fed
--- /dev/null
+++ b/tests/test_integration.py
@@ -0,0 +1,306 @@
+import pytest
+import json
+import yaml
+from click.testing import CliRunner
+from pathlib import Path
+from json_to_openapi.cli import main
+from json_to_openapi.schema_generator import OpenAPIGenerator
+
+
+class TestIntegration:
+    """Integration test cases."""
+
+    @pytest.fixture
+    def runner(self):
+        return CliRunner()
+
+    @pytest.fixture
+    def user_schema_file(self, tmp_path):
+        data = {
+            "users": [
+                {
+                    "id": 1,
+                    "name": "Alice",
+                    "email": "alice@example.com",
+                    "age": 30,
+                    "active": True,
+                    "created_at": "2024-01-15T10:30:00Z",
+                    "tags": ["admin", "user"],
+                    "metadata": {
+                        "department": "Engineering",
+                        "level": 5
+                    }
+                },
+                {
+                    "id": 2,
+                    "name": "Bob",
+                    "email": "bob@example.com",
+                    "age": 25,
+                    "active": False,
+                    "created_at": "2024-02-20T14:00:00Z",
+                    "tags": ["user"],
+                    "metadata": {
+                        "department": "Sales",
+                        "level": 3
+                    }
+                }
+            ],
+            "total": 2
+        }
+        file_path = tmp_path / "users.json"
+        file_path.write_text(json.dumps(data))
+        return file_path
+
+    @pytest.fixture
+    def product_schema_file(self, tmp_path):
+        data = {
+            "products": [
+                {
+                    "id": 101,
+                    "name": "Laptop",
+                    "price": 999.99,
+                    "in_stock": True,
+                    "category": "Electronics",
+                    "variants": [
+                        {"color": "black", "sku": "LAP-BLK-001"},
+                        {"color": "silver", "sku": "LAP-SLV-001"}
+                    ]
+                },
+                {
+                    "id": 102,
+                    "name": "Mouse",
+                    "price": 29.99,
+                    "in_stock": True,
+                    "category": "Electronics",
+                    "variants": [
+                        {"color": "white", "sku": "MSE-WHT-001"}
+                    ]
+                }
+            ]
+        }
+        file_path = tmp_path / "products.json"
+        file_path.write_text(json.dumps(data))
+        return file_path
+
+    def test_end_to_end_user_schema(self, runner, user_schema_file, tmp_path):
+        """Test end-to-end conversion of user schema."""
+        output_file = tmp_path / "users_openapi.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(user_schema_file),
+            "-o", str(output_file),
+            "-t", "Users API",
+            "-v", "1.0.0",
+            "-d", "API for managing users"
+        ])
+
+        assert result.exit_code == 0
+        assert output_file.exists()
+
+        content = output_file.read_text()
+        spec = yaml.safe_load(content)
+
+        assert spec["openapi"] == "3.0.3"
+        assert spec["info"]["title"] == "Users API"
+        assert spec["info"]["version"] == "1.0.0"
+        assert spec["info"]["description"] == "API for managing users"
+
+    def test_end_to_end_product_schema(self, runner, product_schema_file, tmp_path):
+        """Test end-to-end conversion of product schema."""
+        output_file = tmp_path / "products_openapi.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(product_schema_file),
+            "-o", str(output_file),
+            "-t", "Products API"
+        ])
+
+        assert result.exit_code == 0
+        assert output_file.exists()
+
+        content = output_file.read_text()
+        spec = yaml.safe_load(content)
+
+        assert spec["openapi"] == "3.0.3"
+        assert spec["info"]["title"] == "Products API"
+
+    def test_batch_processing(self, runner, user_schema_file, product_schema_file, tmp_path):
+        """Test batch processing of multiple JSON files."""
+        output_dir = tmp_path / "output"
+        output_dir.mkdir()
+
+        result = runner.invoke(main, [
+            "batch",
+            str(tmp_path / "*.json"),
+            "-o", str(output_dir),
+            "-f", "yaml"
+        ])
+
+        assert result.exit_code == 0
+        assert "Successfully processed 2 files" in result.output
+
+        assert (output_dir / "users.yaml").exists()
+        assert (output_dir / "products.yaml").exists()
+
+    def test_combined_batch_processing(self, runner, user_schema_file, product_schema_file, tmp_path):
+        """Test combined batch processing."""
+        output_dir = tmp_path / "combined_output"
+        output_dir.mkdir()
+
+        result = runner.invoke(main, [
+            "batch",
+            str(tmp_path / "*.json"),
+            "-o", str(output_dir),
+            "-c",
+            "-f", "yaml"
+        ])
+
+        assert result.exit_code == 0
+
+    def test_spec_validity(self, runner, user_schema_file, tmp_path):
+        """Test that generated spec is valid OpenAPI 3.0.3."""
+        output_file = tmp_path / "valid_spec.yaml"
+
+        runner.invoke(main, [
+            "convert",
+            str(user_schema_file),
+            "-o", str(output_file)
+        ])
+
+        result = runner.invoke(main, ["validate", str(output_file)])
+        assert result.exit_code == 0
+        assert "Validation passed" in result.output
+
+    def test_json_output_format(self, runner, user_schema_file, tmp_path):
+        """Test JSON output format."""
+        output_file = tmp_path / "spec.json"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(user_schema_file),
+            "-o", str(output_file),
+            "-f", "json"
+        ])
+
+        assert result.exit_code == 0
+        content = output_file.read_text()
+        spec = json.loads(content)
+
+        assert spec["openapi"] == "3.0.3"
+        assert "info" in spec
+        assert "paths" in spec
+
+    def test_custom_endpoint_path(self, runner, user_schema_file, tmp_path):
+        """Test custom endpoint path."""
+        output_file = tmp_path / "custom_path.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(user_schema_file),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0
+        content = output_file.read_text()
+        spec = yaml.safe_load(content)
+
+        assert "/" in spec["paths"] or "/users" in spec["paths"]
+
+
+class TestEdgeCases:
+    """Test edge cases and error handling."""
+
+    @pytest.fixture
+    def runner(self):
+        return CliRunner()
+
+    def test_empty_object(self, runner, tmp_path):
+        """Test handling of empty object."""
+        data = {}
+        file_path = tmp_path / "empty.json"
+        file_path.write_text(json.dumps(data))
+
+        output_file = tmp_path / "output.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(file_path),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0
+        assert output_file.exists()
+
+    def test_empty_array(self, runner, tmp_path):
+        """Test handling of empty array."""
+        data = []
+        file_path = tmp_path / "empty_array.json"
+        file_path.write_text(json.dumps(data))
+
+        output_file = tmp_path / "output.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(file_path),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0
+
+    def test_nested_deep_structure(self, runner, tmp_path):
+        """Test handling of deeply nested structures."""
+        data = {"level1": {"level2": {"level3": {"level4": {"level5": "deep"}}}}}
+        file_path = tmp_path / "deep.json"
+        file_path.write_text(json.dumps(data))
+
+        output_file = tmp_path / "output.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(file_path),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0
+
+    def test_special_characters_in_strings(self, runner, tmp_path):
+        """Test handling of special characters."""
+        data = {
+            "message": "Hello \"World\"!",
+            "path": "/api/v1/users",
+            "email": "user@example.com"
+        }
+        file_path = tmp_path / "special.json"
+        file_path.write_text(json.dumps(data))
+
+        output_file = tmp_path / "output.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(file_path),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0
+
+    def test_unicode_characters(self, runner, tmp_path):
+        """Test handling of unicode characters."""
+        data = {
+            "name": "日本語 Test",
+            "emoji": "🚀",
+            "chinese": "你好"
+        }
+        file_path = tmp_path / "unicode.json"
+        file_path.write_text(json.dumps(data))
+
+        output_file = tmp_path / "output.yaml"
+
+        result = runner.invoke(main, [
+            "convert",
+            str(file_path),
+            "-o", str(output_file)
+        ])
+
+        assert result.exit_code == 0