cs2-masked-inspect (Go)

Pure Go library for encoding and decoding CS2 masked inspect links — no runtime dependencies, requires Go 1.21+.

Installation

go get github.com/vlydev/cs2-masked-inspect-go

Usage

Deserialize a CS2 inspect link

import "github.com/vlydev/cs2-masked-inspect-go/cs2inspect"

// Accepts raw hex, steam:// URLs, hybrid S/A/D URLs, and classic inspect URLs.
item, err := cs2inspect.Deserialize("steam://rungame/730/76561202255233023/+csgo_econ_action_preview%20E3F3...")
if err != nil {
    log.Fatal(err)
}
fmt.Println(item.DefIndex)   // 7 (AK-47)
fmt.Println(item.PaintIndex) // 422
fmt.Println(item.PaintSeed)  // 922
if item.PaintWear != nil {
    fmt.Printf("%.5f\n", *item.PaintWear) // 0.04121
}
fmt.Println(len(item.Stickers)) // 5

Serialize

pw := float32(0.005411375779658556)
data := &cs2inspect.ItemPreviewData{
    DefIndex:   60,
    PaintIndex: 440,
    PaintSeed:  353,
    Rarity:     5,
    PaintWear:  &pw,
}
hexStr, err := cs2inspect.Serialize(data)
if err != nil {
    log.Fatal(err)
}
fmt.Println(hexStr)
// "00183C20B803280538E9A3C5DD0340E102C246A0D1"

IsMasked / IsClassic

// Returns true if the link contains a decodable protobuf payload.
cs2inspect.IsMasked("steam://rungame/730/.../+csgo_econ_action_preview%20A00183C...")
// true

// Returns true if the link is a classic S/A/D format with a decimal D value.
cs2inspect.IsClassic("steam://rungame/730/.../+csgo_econ_action_preview%20S123A456D789")
// true

Working with stickers and keychains

item, _ := cs2inspect.Deserialize(hexStr)

for _, s := range item.Stickers {
    fmt.Printf("Slot %d: StickerID=%d", s.Slot, s.StickerID)
    if s.Wear != nil {
        fmt.Printf(" wear=%.4f", *s.Wear)
    }
    fmt.Println()
}

for _, kc := range item.Keychains {
    fmt.Printf("Keychain StickerID=%d", kc.StickerID)
    if kc.HighlightReel != nil {
        fmt.Printf(" highlightReel=%d", *kc.HighlightReel)
    }
    fmt.Println()
}

Gen codes

Generate a Steam inspect URL from item parameters (defindex, paintindex, paintseed, paintwear):

import "github.com/vlydev/cs2-masked-inspect-go/cs2inspect"

// Generate a Steam inspect URL
url, err := cs2inspect.Generate(7, 474, 306, 0.22540508, nil)

// Convert to gen code
item := &cs2inspect.ItemPreviewData{DefIndex: 7, PaintIndex: 474, PaintSeed: 306}
pw := float32(0.22540508); item.PaintWear = &pw
code := cs2inspect.ToGenCode(item, "!gen") // "!gen 7 474 306 0.22540508"

// Parse a gen code
item2, err := cs2inspect.ParseGenCode("!gen 7 474 306 0.22540508")

// Convert an existing inspect link directly to a gen code
code, err := cs2inspect.GenCodeFromLink("steam://rungame/730/76561202255233023/+csgo_econ_action_preview%20001A...", "!gen")
// "!gen 7 474 306 0.22540508"

API Reference

Functions

Function	Signature	Description
Serialize	func Serialize(data *ItemPreviewData) (string, error)	Encode item data to uppercase hex. Key byte is always 0x00.
Deserialize	func Deserialize(input string) (*ItemPreviewData, error)	Decode hex payload or any inspect URL format.
IsMasked	func IsMasked(link string) bool	True if the link has an embedded protobuf payload.
IsClassic	func IsClassic(link string) bool	True if the link is a classic S/A/D format with decimal D.

ItemPreviewData fields

Go Field	Proto Field	Wire Type	Description
AccountID	1	varint	Steam account ID
ItemID	2	varint (uint64)	Asset ID
DefIndex	3	varint	Item definition index
PaintIndex	4	varint	Skin/paint index
Rarity	5	varint	Item rarity
Quality	6	varint	Item quality
PaintWear	7	varint (float32 bits)	Wear value 0.0–1.0, nil = omitted
PaintSeed	8	varint	Pattern seed (0–1000)
KillEaterScoreType	9	varint	StatTrak kill type
KillEaterValue	10	varint	StatTrak counter
CustomName	11	length-delimited	Name tag
Stickers	12	length-delimited (repeated)	Applied stickers
Inventory	13	varint	Inventory flags
Origin	14	varint	Item origin
QuestID	15	varint	Quest ID
DropReason	16	varint	Drop reason
MusicIndex	17	varint	Music kit index
EntIndex	18	varint (int32)	Entity index
PetIndex	19	varint	Pet/agent index
Keychains	20	length-delimited (repeated)	Keychains (same Sticker type)

Sticker fields

Go Field	Proto Field	Wire Type	Description
Slot	1	varint	Sticker slot (0–4)
StickerID	2	varint	Sticker definition ID
Wear	3	fixed32 LE	Sticker wear, nil = omitted
Scale	4	fixed32 LE	Scale, nil = omitted
Rotation	5	fixed32 LE	Rotation, nil = omitted
TintID	6	varint	Tint ID
OffsetX	7	fixed32 LE	X offset, nil = omitted
OffsetY	8	fixed32 LE	Y offset, nil = omitted
OffsetZ	9	fixed32 LE	Z offset, nil = omitted
Pattern	10	varint	Pattern index
HighlightReel	11	varint	Highlight reel, nil = omitted

Validation rules

Serialize:

• PaintWear must be in [0.0, 1.0] if set; returns error otherwise.
• CustomName must not exceed 100 characters; returns error otherwise.

Deserialize:

• Hex payload must not exceed 4096 characters; returns error otherwise.
• Decoded payload must be at least 6 bytes; returns error otherwise.

Binary format

[key_byte] [proto_bytes XOR'd with key] [4-byte checksum XOR'd with key]

• key_byte = 0x00 for tool-generated links (no XOR).
• key_byte != 0x00 for native CS2 links (XOR every byte including key itself).

Checksum:

buffer  = [0x00] + proto_bytes
crc     = CRC32-IEEE(buffer)
xored   = (crc & 0xFFFF) ^ (uint32(len(proto_bytes)) * crc)  [unsigned 32-bit]
checksum = big-endian uint32(xored & 0xFFFFFFFF)

Test vectors

Vector	Key	DefIndex	PaintIndex	PaintSeed	PaintWear	Notes
00183C20B803280538E9A3C5DD0340E102C246A0D1	0x00	60	440	353	≈0.005411	Tool-generated
E3F33674… (96 bytes)	0xE3	7 (AK-47)	422	922	≈0.04121	Native CS2, 5 stickers
00180720DA03…	0x00	7	474	306	≈0.6337	CSFloat vector A
00180720C80A…	0x00	–	1352	–	≈0.99	CSFloat vector B, 4 stickers
A2B2A2BA…	0xA2	1355	–	–	nil	CSFloat vector C, 1 keychain

Running tests

go test ./...

Contributing

Pull requests are welcome. Please ensure all tests pass and follow standard Go conventions.

License

MIT — see LICENSE.