API consistency refers to the degree to which an API behaves predictably and reliably across different environments and scenarios. Scaling an API involves increasing its capacity to handle a larger volume of requests or a higher load; as you do this, you need to keep API consistency in mind.
Here are some tips for ensuring API consistency while scaling: Design the API for scaling.
Explicitly spell out the extent of the API design audit, including which APIs and related documentation will be incorporated.
API design: The audit should review the design of the API, including the naming conventions used for resources, methods and parameters, as well as the consistency and clarity of the API documentation.