diff --git a/docs/recipes.md b/docs/recipes.md
new file mode 100644
index 0000000..de5fe2c
--- /dev/null
+++ b/docs/recipes.md
@@ -0,0 +1,85 @@
+## Convert OpenAPIv2 to OpenAPIv3
+
+To convert OpenAPIv2 to OpenAPIv3, you can use the `prance` library. Install it using (after activate the virtual environment):
+
+```bash
+pip install prance
+```
+
+Then, you can use the following code:
+
+```bash
+prance convert openapi_v2.yaml openapi_v3.yaml
+```
+
+### Some Issues may exist in the generated OpenAPIv3 file
+
+- `description` field in some places may convert as multi-line string (bad format). use this code to fix it:
+
+```python
+import yaml
+import re
+
+def process_descriptions(data):
+    """
+    Recursively process a dictionary/list to modify all 'description' fields to a single line.
+    """
+    if isinstance(data, dict):
+        for key, value in data.items():
+            if key == 'description' and isinstance(value, str):
+                # Replace newlines, tabs, and multiple spaces with a single space
+                cleaned_description = re.sub(r'\s+', ' ', value.strip())
+                data[key] = cleaned_description
+            else:
+                process_descriptions(value)
+    elif isinstance(data, list):
+        for item in data:
+            process_descriptions(item)
+
+def modify_yaml_file(input_file, output_file):
+    try:
+        # Read the YAML file
+        with open(input_file, 'r', encoding='utf-8') as file:
+            yaml_data = yaml.safe_load(file)
+
+        # Process all description fields
+        process_descriptions(yaml_data)
+
+        # Write the modified data to a new YAML file
+        with open(output_file, 'w', encoding='utf-8') as file:
+            yaml.dump(yaml_data, file, allow_unicode=True, sort_keys=False, default_flow_style=False, width=1000)
+
+        print(f"Modified YAML file saved as: {output_file}")
+    except yaml.YAMLError as ye:
+        print(f"YAML parsing error: {ye}")
+    except Exception as e:
+        print(f"Error processing YAML file: {e}")
+
+# Example usage
+input_yaml = 'openapi_v3.yaml'  # Replace with your input YAML file path
+output_yaml = 'openapi_v3_output.yaml'  # Replace with desired output YAML file path
+modify_yaml_file(input_yaml, output_yaml)
+```
+
+- `successfull_response` in `responses` section. this is not a standard field in OpenAPIv3. You can remove it. remove it and put `example` right after `schema` field in `responses` section.
+
+```yaml
+responses:
+  "200":
+    description: successful operation
+    content:
+      application/json:
+        schema:
+          $ref: "#/components/schemas/API_Entities_AccessRequester"
+        example:
+          id: 1
+          username: ali
+          name: ali karami
+          state: active
+          created_at: 2012-10-22T14:13:35Z
+          access_level: 20
+```
+
+- `type:file` in `parameters` or `schema` section. this is not a standard field in OpenAPIv3. You can replace it with `type: string` and add `format: binary` field to it.
+
+- `application/x-tar` in `content` section. this may be cause of error in some cases. you can remove it and replace it with `application/octet-stream` or other standard types for binary files.