Summary: The community price reflects the base item (immutable properties), while suggested accounts for instance-specific modifications.
When parsing the Backpack.tf websocket API, it is important to understand the distinct roles of the three price fields:
- Usage of
suggested: This field is the primary source for modified items (Parts, Paint, KS), as it accounts for those properties.
- Usage of
community: This field acts as a baseline for the base item. It ignores attachments and may be null for specific variants.
- Usage of
steam: This field matches the Steam Community Market hash name and may be missing for complex modified items that lack a direct SCM listing.
Price Divergence in Killstreak Variants
The most striking proof of this architecture comes from analyzing items where the “Immutable” base value diverges from the “Instance” value.
Case 1: The Invisible Killstreak (Null Community Price)
For high-tier killstreaks, the community price often vanishes entirely because users cannot vote on specific tiers.
Item: Professional Killstreak Festive Huntsman
- Observation: The
community field is null, but suggested correctly values the Pro Kit (~6 keys) on top of the base bow (~4.6 keys).
// Tier 3: Professional Killstreak Festive Huntsman
"price": {
"community": null, // <--- Fails to match "Pro KS" variant
"suggested": { // <--- Algorithmic sum (Base + Pro Kit)
"raw": 603.14,
"short": "10.25 keys"
}
}
Compare this to the base item, where they match perfectly:
// Tier 0: The Festive Huntsman
"price": {
"community": { // <--- Matches base pricelist
"short": "4.1–5.1 keys";
},
"suggested": {
"short": "4.6 keys"
}
}
Case 2: The “Blind” Community Price (Parts & Paint)
When an item does have a community price, that price is “blind” to attachments.
Item: Strange Thermal Tracker (with Paint & Parts)
- Observation:
community returns the cheap base Strange price. suggested adds nearly a key of value for the parts.
"price": {
"community": {
"value": 0.75, // <--- Base Strange Price (Blind to parts)
"short": "0.75–1.1 keys"
},
"suggested": {
"short": "1.67 keys" // <--- Includes Parts & Paint Value
}
}
The Three Pillars of Value (Definitions)
1. steam: SCM Listing
- What it is: Lowest/Median SCM listing.
- Behavior: Strictly tied to the Steam Market Hash Name. Often missing (
null) for kit-applied items because SCM listings are for the base item or the kit, not the combined asset.
2. community: Immutable Baseline
- What it is: User-voted suggestions from the main stats page.
- Behavior: A Baseline Lookup based on Defindex + Quality. It blindly ignores mutable properties.
3. suggested: Instance Value
- What it is: Algorithmic estimation of the specific instance.
- Behavior: Sums
Base + Value(Parts) + Value(Paints) + Value(Killstreak). This is your "True" market estimate for modified items.
joekiller 