In that case, it would be nice if the skill description for Pirate Bellow would tell you how many times it triggers in chat, so we could see how much it has been upgraded. That would be a KoL change. Some KoL dev should suggest it.
You can reverse engineer summonAnnoyanceCost to tell how many times the skill has been upgraded, and from that, derive the cost in the Swagger Shop to buy the next upgrade. Do we do that, or does the Coinmasters Frame always say the cost is 5,000 swagger?
Fun facts: if you buy your first Essence of Annoyance in the Swagger Shop, it leaves it there for the original cost - until you leave and go away. If you have not used it before coming back, it is not on offer the next time you go in; apparently you cannot buy another until you have used the previous one - and presumably, the Swagger Shop will update with the higher price, once you have done so. I don't know what would happen if you try to buy a second one before you leave the Swagger Shop with the first one; it is clearly visible in the shop inventory, but KoL will probably reject it.
(I wasn't brave enough to try to buy a second for 5,000 - the price it showed me - because I actually had more than 11,000 swagger left after buying my first, and I wasn't willing to spend that much for a second vial. It probably would have just rejected the attempt, since I had the first vial in inventory, but, who knows...)