With no professional QA experience yet, the resume leads with proof rather than tenure. A Postman collection you wrote against a public API, a small REST Assured or pytest suite you can describe, a bug you reproduced and reported properly. Name the endpoint, the assertion, and what broke. That is more convincing than a summary claiming familiarity with API testing concepts.
An API testing resume for 2 years of experience is where most people stall, because the tool list is finally long and the bullets are still tasks. Cut the task language. Replace "wrote test cases for REST APIs" with the count of endpoints under automated coverage, the suite you moved into CI, and the regression window that shrank because of it. Two years of real work has numbers in it if you go and look for them.
At senior or lead level the resume stops being about tools at all. It is about the framework you chose and why, the contract testing you introduced, the flaky suite you stabilized, the test data strategy, and the people you brought along. Keep REST Assured, Postman, and JMeter in the skills block for the parser, then spend the bullets on judgment.
An API integration analyst or API developer resume borrows the same spine and shifts the emphasis toward design and consumption: the integrations you shipped, the auth models you handled, the versioning and deprecation you managed, the partners you unblocked. Same layout, same scoring, different center of gravity.