The test plan generator determines which tests need to run for a given set of Chrome OS builds.
This is generally intended to be executed by a LUCI recipe. A service account credentials file is needed in order to fetch CL data from Gerrit.
go run cmd/test_plan_generator/main.go gen-test-plan \ --input_json=/path/to/input.json \ --output_json=/path/for/output.json \ --service-account-json=/path/to/service-account-json-file.json
See the sample directory for data that can be used for local runs.