Designing APIs involves providing users with a degree of control over a service, which often necessitates additional functionality beyond basic HTTP verbs and resource URLs, such as pagination. Parametrization is crucial for this purpose, allowing various methods of adding parameters to requests, like through query strings, headers, or the body of POST requests. The choice of where to place these parameters—whether in headers or query strings—depends on factors such as sensitivity, dynamism, and developer experience. For example, headers are suitable for static parameters like authentication tokens, while query strings are ideal for dynamic parameters like filters. Although methods like square brackets or separating values by commas can be used for handling array parameters, careful consideration is needed to maintain readability and security, avoiding sensitive data in query strings due to their visibility. Additionally, API design should focus on understanding usage patterns to ensure the most common use cases are easily accomplished and to prevent errors, with tools like Moesif providing analytics to help monitor and optimize API traffic.