> ## Documentation Index > Fetch the complete documentation index at: https://gofastmcp.com/llms.txt > Use this file to discover all available pages before exploring further. # formatters # `fastmcp.utilities.openapi.formatters` Parameter formatting functions for OpenAPI operations. ## Functions ### `format_array_parameter` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} format_array_parameter(values: list, parameter_name: str, is_query_parameter: bool = False) -> str | list ``` Format an array parameter according to OpenAPI specifications. **Args:** * `values`: List of values to format * `parameter_name`: Name of the parameter (for error messages) * `is_query_parameter`: If True, can return list for explode=True behavior **Returns:** * String (comma-separated) or list (for query params with explode=True) ### `format_deep_object_parameter` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} format_deep_object_parameter(param_value: dict, parameter_name: str) -> dict[str, str] ``` Format a dictionary parameter for deep-object style serialization. According to OpenAPI 3.0 spec, deepObject style with explode=true serializes object properties as separate query parameters with bracket notation. For example, `{"id": "123", "type": "user"}` becomes `param[id]=123¶m[type]=user`. **Args:** * `param_value`: Dictionary value to format * `parameter_name`: Name of the parameter **Returns:** * Dictionary with bracketed parameter names as keys ### `generate_example_from_schema` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} generate_example_from_schema(schema: JsonSchema | None) -> Any ``` Generate a simple example value from a JSON schema dictionary. Very basic implementation focusing on types. ### `format_json_for_description` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} format_json_for_description(data: Any, indent: int = 2) -> str ``` Formats Python data as a JSON string block for Markdown. ### `format_description_with_responses` ```python theme={"theme":{"light":"snazzy-light","dark":"dark-plus"}} format_description_with_responses(base_description: str, responses: dict[str, Any], parameters: list[ParameterInfo] | None = None, request_body: RequestBodyInfo | None = None) -> str ``` Formats the base description string with response, parameter, and request body information. **Args:** * `base_description`: The initial description to be formatted. * `responses`: A dictionary of response information, keyed by status code. * `parameters`: A list of parameter information, including path and query parameters. Each parameter includes details such as name, location, whether it is required, and a description. * `request_body`: Information about the request body, including its description, whether it is required, and its content schema. **Returns:** * The formatted description string with additional details about responses, parameters, * and the request body.