Function json_content 

pub fn json_content(json: Value) -> Value

Helper to create a JSON content response

Creates a standard MCP JSON content response with structured data:

{
  "content": [{
    "type": "json",
    "json": { ... }
  }]
}

Use case: Structured data for programmatic clients

Example

fn handle_get_product(args: &Value) -> Result<Value, String> {
    let product = get_product_from_db()?;
    Ok(json_content(serde_json::to_value(product)?))
}