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SDL API: https://docs.o-ran-sc.org/projects/o-ran-sc-ric-plt-sdl/en/latest/user-guide.html
Xapp onboarding : old link (likely outdated): and deployment: check section "RIC applications" in https://docs.o-ran-sc.org/projects/o-ran-sc-it-devdep/en/latest/developer-guide.htmlinstallation-guides.html#ric-applications on how to use the dms_cli to onboard and deploy xApps.
Generally check the read-the-docs pages: https://docs.o-ran-sc.org/en/latest/projects.html#near-realtime-ran-intelligent-controller-ric
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