These bags aren’t airtight and so I wouldn’t keep herbs in them for a long time. However, they could be stored in an airtight container until right before you give them to someone, and suggest they do the same once they get them. I re-read your question and realize you’re talking about storage bags and not just tea bags for infusing! In that case, I have some more thoughts.
Many companies that claim to make compostable materials that are only compostable under very specific conditions and even though, may take a very long time. I’ve done quite a lot of research in this area and have been continually disappointed with what I’ve learned. Further, compostable materials cost more to purchase, and often they end up in the landfill if people don’t dispose of them properly, thereby, defeating the good intentions of the person providing them. When researching, It’s a good idea to contact the company and find out the details about how their materials are compostable. You may find that a recyclable option is a more affordable and perhaps, a more environmentally conscious choice.
-Rootree is a Canadian company making compostable packaging. This option may only be available for large orders but you can look into it:https://rootree.ca/