Is API information constantly being mutated?

[zxzfff.8013]

Recently, I started working on a project using the Guild Wars 2 API. This might seem like a random question, but it's relevant to my project. I would like to know if the values in https://api.guildwars2.com/v2/commerce/prices change. Meaning will there be more IDs added when new items are added to the game? Also, does https://api.guildwars2.com/v2/commerce/prices change only show the IDs of items that are currently being sold on the TP (Meaning if some item is not being sold in TP, it won't show up in the list of IDs)? I would also like to know the same things for https://api.guildwars2.com/v2/items.

[Daniel Snider.6241]

Data you get from the Guild Wars 2 API comes from many different live sources, depending on what you're requesting. For example, https://api.guildwars2.com/v2/items will automatically update to show new items as they are added to the game. https://api.guildwars2.com/v2/commerce/prices will automatically update as items are added and removed from the trading post.

Compare https://api.guildwars2.com/v2/items/6459versus https://api.guildwars2.com/v2/commerce/prices/6459

It is listed in items, but since it is not listed on the TP it does not show in commerce/prices.