The firebrand Franco-Bosnian wore a face like thunder as he prowled the touchline in a pinstripe suit gesticulating furiously as Japan wasted first-half chances, with debutant Kengo Kawamata coming closest by heading against the bar after 20 minutes.
Honda and Shinji Kagawa were introduced on the hour mark, quickly followed by Okazaki, and all three made an impact as the Blue Samurai blew out the cobwebs after their Asian Cup flop in January.
The 62-year-old Halilhodzic, who led Algeria to the knockout stages of last year's World Cup in Brazil, made sweeping changes for his first game in Oita, western Japan, but the arrival of Honda and Kagawa gave the home side an instant lift.
Former Bayern Munich loanee Takashi Usami almost marked his debut with a goal just before the final whistle, hitting the post with a curling effort, but Halilhodzic will have a clearer idea of his best side before the 2018 Asian World Cup qualifiers begin in June.
Former Yugoslavia striker Halilhodzic, who has promised to restore Japan's shattered confidence, will have another opportunity to tinker when his side face Uzbekistan in Tokyo on Tuesday.
Japan exited the 2014 FIFA World Cup™ with barely a whimper under Italian Alberto Zaccheroni before their AFC Asian Cup defence ended in an embarrassing quarter-final defeat to the United Arab Emirates on penalties.