Earlier quoted context omitted.
We are not providing opening times yet - we just check if place is permanently closed or not. But it is in the works under our experimental enrichment API (which is not yet open to public)
I started scraping restaurant websites in Zürich and extracted and hand-checked opening hours in the OpenStreetMap format. The goal is to build a corpus for evaluation purposes which maps website texts to correct opening hours strings for all restaurants in Switzerland. Maybe you can use that to benchmark your own hours extracting system... https://github.com/wipfli/opening-hours/
I also launched recently a project to extract opening hours from OSM websites : https://codeberg.org/raphaelb/poi-complete
I also added a very basic web interface for validating the predictions: https://poicomplete.raphaelb.net
I don't know how well does Haiku handle OSM opening hours syntax, but with Kimi K2.5, I got better results when I asked it to provide opening hour ranges for every day of the week, and then constructed the opening hours manually.