Enhance docstring

Change-Id: Ifedaa18d4d27b5d699d7fe02598aa1869c498c8c
Reduce nesting of `retry` decorator implementation

Change-Id: Ib71b5d2a7204b6b4309ee60455d30dd36e6486fa
Various fixups

Change-Id: Iaf9f50fb08786d5ba10496fa63274f9cc689cce2