PulseBow Posted April 26, 2021 Share Posted April 26, 2021 When the backpack loads and there are no issues, many of my untradable weapon drops (not all) are shown as tradable and can be listed. While using the fallback, only the actually tradable items are shown as tradable? Issue has probably been brought up before but I can only find a thread for the other way around. Fallback: Last good inventory (Mad Milk out of view but tradable) Link to comment Share on other sites More sharing options...
Tasty Salamanders Posted April 26, 2021 Share Posted April 26, 2021 This isn't a backpack.tf glitch, but rather due to the way items are handled by Valve. Untradable items typically have an untradable flag, "untradable drops" don't actually have an untradable flag because they are actually tradable, the trade restriction is actually based on the account not the actual items. When an inventory properly loads (or the last good inventory is loaded) the information comes straight from the Steam API, and since the items don't actually have untradable tags they show up as tradable on backpack. Fallback doesn't use the API and instead used other information sources (such as scraped information) which does pick up the items are untradable. Link to comment Share on other sites More sharing options...
Amattica Posted April 26, 2021 Share Posted April 26, 2021 How strange... uhh. I mean unusual. I mean- oh you know what i mean. Link to comment Share on other sites More sharing options...
PulseBow Posted April 26, 2021 Author Share Posted April 26, 2021 1 hour ago, Tasty Salamanders said: This isn't a backpack.tf glitch, but rather due to the way items are handled by Valve. Untradable items typically have an untradable flag, "untradable drops" don't actually have an untradable flag because they are actually tradable, the trade restriction is actually based on the account not the actual items. When an inventory properly loads (or the last good inventory is loaded) the information comes straight from the Steam API, and since the items don't actually have untradable tags they show up as tradable on backpack. Fallback doesn't use the API and instead used other information sources (such as scraped information) which does pick up the items are untradable. You learn something new every day. Link to comment Share on other sites More sharing options...
MeFigaYoma Posted April 27, 2021 Share Posted April 27, 2021 6 hours ago, Tasty Salamanders said: This isn't a backpack.tf glitch, but rather due to the way items are handled by Valve. Untradable items typically have an untradable flag, "untradable drops" don't actually have an untradable flag because they are actually tradable, the trade restriction is actually based on the account not the actual items. When an inventory properly loads (or the last good inventory is loaded) the information comes straight from the Steam API, and since the items don't actually have untradable tags they show up as tradable on backpack. Fallback doesn't use the API and instead used other information sources (such as scraped information) which does pick up the items are untradable. This is mostly correct, except for the part about information sources. Proper inventory loading uses the TF2 WebAPI, created specifically for TF2 (even before trading was added). This source returns full information about TF2 items, including all their possible quirks. Recently this has been unreliable, often failing most attempts for several hours. I think it's a load-related issue since I've noticed that it's more reliable around European morning / American late night, and less reliable around European night / American early evening, when more people are playing, presumably. What backpack.tf calls "fallback inventory" is the result of the Steam inventory API. This gives exactly the same information you can see when you view your inventory on steam, nothing more, nothing less. This was introduced when Steam trading was added, and its information and format is standardised across all games using the steam item system (plus steam items such as trading cards). As a result, it does not return some TF2-specific item information, such as item origin, original ID, item position in backpack, or item level (actually, it returns a string called "type" as one of the attributes for each item, which contains the item level only for some items, e.g. a unique YER is "type": "Level 1 Knife", but OP's Strange Citizen Cane is "type": "Strange Hat - Points Scored: 3540"). This is why, when loading from a fallback inventory, backpack.tf shows everything as Level 0 and Origin: Timed Drop and doesn't update item histories or display item position in the backpack correctly. This API nearly never fails (unless Steam is down, of course). I have taken a look at the results returned by both APIs on OP's backpack, and I can confirm that the TF2 WebAPI result doesn't specify that his untradeable-because-F2P weapon drops are untradable, while the Steam Inventory API does. I am not certain, but I assume the items become tradable once you upgrade to premium, so it would make sense that it's an account-based restriction, rather than an item attribute. If anyone is curious about what the API results actually show, here are the full results for a particular item in OP's backpack, with some comments by me: https://pastebin.com/twTeEhxk Link to comment Share on other sites More sharing options...
PulseBow Posted April 28, 2021 Author Share Posted April 28, 2021 On 4/27/2021 at 2:14 AM, MeFigaYoma said: This is mostly correct, except for the part about information sources. Proper inventory loading uses the TF2 WebAPI, created specifically for TF2 (even before trading was added). This source returns full information about TF2 items, including all their possible quirks. Recently this has been unreliable, often failing most attempts for several hours. I think it's a load-related issue since I've noticed that it's more reliable around European morning / American late night, and less reliable around European night / American early evening, when more people are playing, presumably. What backpack.tf calls "fallback inventory" is the result of the Steam inventory API. This gives exactly the same information you can see when you view your inventory on steam, nothing more, nothing less. This was introduced when Steam trading was added, and its information and format is standardised across all games using the steam item system (plus steam items such as trading cards). As a result, it does not return some TF2-specific item information, such as item origin, original ID, item position in backpack, or item level (actually, it returns a string called "type" as one of the attributes for each item, which contains the item level only for some items, e.g. a unique YER is "type": "Level 1 Knife", but OP's Strange Citizen Cane is "type": "Strange Hat - Points Scored: 3540"). This is why, when loading from a fallback inventory, backpack.tf shows everything as Level 0 and Origin: Timed Drop and doesn't update item histories or display item position in the backpack correctly. This API nearly never fails (unless Steam is down, of course). I have taken a look at the results returned by both APIs on OP's backpack, and I can confirm that the TF2 WebAPI result doesn't specify that his untradeable-because-F2P weapon drops are untradable, while the Steam Inventory API does. I am not certain, but I assume the items become tradable once you upgrade to premium, so it would make sense that it's an account-based restriction, rather than an item attribute. If anyone is curious about what the API results actually show, here are the full results for a particular item in OP's backpack, with some comments by me: https://pastebin.com/twTeEhxk That was a good explanation, and I read through the Your Eternal Reward results (mini-crit on lunchbox wtf). Also for some reason it makes me happy that you mentioned my hat. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.