You can use the Polaris PSA API to fetch and modify your Polaris PSA data.
The Polaris PSA API is based on GraphQL, an open-source API standard that allows for declarative data fetching (i.e. clients query a single endpoint for data).
GraphQL offers more efficient data loading the traditional REST APIs, and allows for faster development cycles. Plus, it supports any programming language or framework.
If you’re not familiar with GraphQL, you can learn more about it on the GraphQL site.