README

Pure PHP 8.2+ library for encoding and decoding CS2 masked inspect links — no runtime dependencies.

Installation

composer require vlydev/cs2-masked-inspect

Usage

Deserialize a CS2 inspect link

use VlyDev\Steam\InspectLink;

// Accepts a full steam:// URL or a raw hex string
$item = InspectLink::deserialize(
    'steam://run/730//+csgo_econ_action_preview%20E3F3367440334DE2FBE4C345E0CBE0D3...'
);

echo $item->defindex;   // 7  (AK-47)
echo $item->paintindex; // 422
echo $item->paintseed;  // 922
echo $item->paintwear;  // ~0.04121
echo $item->itemid;     // 46876117973

foreach ($item->stickers as $s) {
    echo $s->stickerId; // 7436, 5144, 6970, 8069, 5592
}

Serialize an item to a hex payload

use VlyDev\Steam\InspectLink;
use VlyDev\Steam\ItemPreviewData;

$data = new ItemPreviewData(
    defindex:   60,
    paintindex: 440,
    paintseed:  353,
    paintwear:  0.005411375779658556,
    rarity:     5,
);

$hex = InspectLink::serialize($data);
// 00183C20B803280538E9A3C5DD0340E102C246A0D1

$url = "steam://run/730//+csgo_econ_action_preview%20{$hex}";

Item with stickers and keychains

use VlyDev\Steam\InspectLink;
use VlyDev\Steam\ItemPreviewData;
use VlyDev\Steam\Sticker;

$data = new ItemPreviewData(
    defindex:   7,
    paintindex: 422,
    paintseed:  922,
    paintwear:  0.04121,
    rarity:     3,
    quality:    4,
    stickers: [
        new Sticker(slot: 0, stickerId: 7436),
        new Sticker(slot: 1, stickerId: 5144, wear: 0.1),
    ],
);

$hex = InspectLink::serialize($data);
$decoded = InspectLink::deserialize($hex); // round-trip

Gen codes

Gen codes are space-separated command strings used on CS2 community servers to spawn items.

Format:

!gen {defindex} {paintindex} {paintseed} {paintwear} [{s0_id} {s0_wear} ... {s4_id} {s4_wear}] [{kc_id} {kc_wear} ...]

Stickers are always represented as 5 slot pairs (padded with 0 0 for empty slots)
Keychains are appended without padding, only for present slots
Float values have trailing zeros stripped (max 8 decimal places); 0.0 becomes "0"

Generate a Steam inspect URL from parameters

use VlyDev\Steam\GenCode;

$url = GenCode::generate(
    defIndex:  7,
    paintIndex: 474,
    paintSeed:  306,
    paintWear:  0.22540508,
    rarity:     6,
);
// steam://rungame/730/76561202255233023/+csgo_econ_action_preview%200018...

Convert an ItemPreviewData to a gen code

use VlyDev\Steam\GenCode;
use VlyDev\Steam\ItemPreviewData;
use VlyDev\Steam\Sticker;

$item = new ItemPreviewData(
    defindex:   7,
    paintindex: 474,
    paintseed:  306,
    paintwear:  0.22540508,
    stickers: [
        new Sticker(slot: 2, stickerId: 7203),
    ],
);

$code = GenCode::toGenCode($item);
// "!gen 7 474 306 0.22540508 0 0 0 0 7203 0 0 0 0 0"

$code = GenCode::toGenCode($item, '!g'); // custom prefix

Parse a gen code string

use VlyDev\Steam\GenCode;

$item = GenCode::parseGenCode('!gen 7 474 306 0.22540508 0 0 0 0 7203 0 0 0 0 0');
echo $item->defindex;    // 7
echo $item->paintindex;  // 474
echo $item->paintseed;   // 306
echo $item->paintwear;   // 0.22540508

$item2 = GenCode::parseGenCode('7 474 306 0.22540508'); // prefix is optional

Convert an existing inspect link directly to a gen code

$code = GenCode::genCodeFromLink('steam://rungame/730/76561202255233023/+csgo_econ_action_preview%20001A...');
// "!gen 7 474 306 0.22540508"

Validation

Use isMasked() and isClassic() to detect the link type without attempting to decode it.

use VlyDev\Steam\InspectLink;

// New masked format (pure hex blob) — can be decoded offline
$maskedUrl = 'steam://run/730//+csgo_econ_action_preview%20E3F3...';
InspectLink::isMasked($maskedUrl);   // true
InspectLink::isClassic($maskedUrl);  // false

// Hybrid format (S/A/D prefix with hex proto after D) — also decodable offline
$hybridUrl = 'steam://rungame/730/.../+csgo_econ_action_preview%20S76561199323320483A50075495125D1101C4C4FCD4AB10...';
InspectLink::isMasked($hybridUrl);   // true
InspectLink::isClassic($hybridUrl);  // false

// Classic format — requires Steam Game Coordinator to fetch item info
$classicUrl = 'steam://rungame/730/.../+csgo_econ_action_preview%20S76561199842063946A49749521570D2751293026650298712';
InspectLink::isMasked($classicUrl);  // false
InspectLink::isClassic($classicUrl); // true

Validation rules

deserialize() enforces:

Rule	Limit	Exception
Hex payload length	max 4,096 characters	`InvalidArgumentException`
Protobuf field count	max 100 per message	`OverflowException`

serialize() enforces:

Field	Constraint	Exception
`paintwear`	`[0.0, 1.0]`	`InvalidArgumentException`
`customname`	max 100 characters	`InvalidArgumentException`

How the format works

Three URL formats are handled:

New masked format — pure hex blob after csgo_econ_action_preview:
```
steam://run/730//+csgo_econ_action_preview%20<hexbytes>
```
Hybrid format — old-style S/A/D prefix, but with a hex proto appended after D (instead of a decimal did):
```
steam://rungame/730/.../+csgo_econ_action_preview%20S<steamid>A<assetid>D<hexproto>
```
Classic format — old-style S/A/D with a decimal did; requires Steam GC to resolve item details.

For formats 1 and 2 the library decodes the item offline. For format 3 only URL parsing is possible.

The hex blob (formats 1 and 2) has the following binary layout:

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

Section	Size	Description
`key_byte`	1 byte	XOR key. `0x00` = no obfuscation (tool links). Other values = native CS2 links.
`proto_bytes`	variable	`CEconItemPreviewDataBlock` protobuf, each byte XOR'd with `key_byte`.
`checksum`	4 bytes	Big-endian uint32, XOR'd with `key_byte`.

Checksum algorithm

$buffer   = "\x00" . $protoBytes;
$crc      = crc32($buffer) & 0xFFFFFFFF;
$xored    = (($crc & 0xFFFF) ^ (strlen($protoBytes) * $crc)) & 0xFFFFFFFF;
$checksum = pack('N', $xored); // big-endian uint32

`paintwear` encoding

paintwear is stored as a uint32 varint whose bit pattern is the IEEE 754 representation of a float32. The library handles this transparently — callers always work with PHP float values.

Proto field reference

CEconItemPreviewDataBlock

Field	Number	Type	Description
`accountid`	1	uint32	Steam account ID (often 0)
`itemid`	2	uint64	Item ID in the owner's inventory
`defindex`	3	uint32	Item definition index (weapon type)
`paintindex`	4	uint32	Skin paint index
`rarity`	5	uint32	Item rarity
`quality`	6	uint32	Item quality
`paintwear`	7	uint32*	float32 reinterpreted as uint32
`paintseed`	8	uint32	Pattern seed (0–1000)
`killeaterscoretype`	9	uint32	StatTrak counter type
`killeatervalue`	10	uint32	StatTrak value
`customname`	11	string	Name tag
`stickers`	12	repeated Sticker	Applied stickers
`inventory`	13	uint32	Inventory flags
`origin`	14	uint32	Origin
`questid`	15	uint32	Quest ID
`dropreason`	16	uint32	Drop reason
`musicindex`	17	uint32	Music kit index
`entindex`	18	int32	Entity index
`petindex`	19	uint32	Pet index
`keychains`	20	repeated Sticker	Applied keychains

Sticker

Field	Number	Type	Description
`slot`	1	uint32	Slot position
`sticker_id`	2	uint32	Sticker definition ID
`wear`	3	float32	Wear (fixed32)
`scale`	4	float32	Scale (fixed32)
`rotation`	5	float32	Rotation (fixed32)
`tint_id`	6	uint32	Tint
`offset_x`	7	float32	X offset (fixed32)
`offset_y`	8	float32	Y offset (fixed32)
`offset_z`	9	float32	Z offset (fixed32)
`pattern`	10	uint32	Pattern (keychains)

Known test vectors

Vector 1 — Native CS2 link (XOR key 0xE3)

E3F3367440334DE2FBE4C345E0CBE0D3E7DB6943400AE0A379E481ECEBE2F36F
D9DE2BDB515EA6E30D74D981ECEBE3F37BCBDE640D475DA6E35EFCD881ECEBE3
F359D5DE37E9D75DA6436DD3DD81ECEBE3F366DCDE3F8F9BDDA69B43B6DE81EC
EBE3F33BC8DEBB1CA3DFA623F7DDDF8B71E293EBFD43382B

Field	Value
`itemid`	`46876117973`
`defindex`	`7` (AK-47)
`paintindex`	`422`
`paintseed`	`922`
`paintwear`	`≈ 0.04121`
`rarity`	`3`
`quality`	`4`
sticker IDs	`[7436, 5144, 6970, 8069, 5592]`

Vector 2 — Tool-generated link (key 0x00)

new ItemPreviewData(defindex: 60, paintindex: 440, paintseed: 353,
                    paintwear: 0.005411375779658556, rarity: 5)

Expected hex:

00183C20B803280538E9A3C5DD0340E102C246A0D1

Running tests

composer install
composer test

Contributing

Bug reports and pull requests are welcome on GitHub.

Fork the repository
Create a branch: git checkout -b my-fix
Make your changes and add tests
Ensure all tests pass: composer test
Open a Pull Request

All PRs require the CI checks to pass before merging.

Author

VlyDev — vladdnepr1989@gmail.com

vlydev / cs2-masked-inspect

Maintainers

Package info

Statistics

Security

README

Installation

Usage

Deserialize a CS2 inspect link

Serialize an item to a hex payload

Item with stickers and keychains

Gen codes

Generate a Steam inspect URL from parameters

Convert an ItemPreviewData to a gen code

Parse a gen code string

Convert an existing inspect link directly to a gen code

Validation

Validation rules

How the format works

Checksum algorithm

`paintwear` encoding

Proto field reference

CEconItemPreviewDataBlock

Sticker

Known test vectors

Vector 1 — Native CS2 link (XOR key 0xE3)

Vector 2 — Tool-generated link (key 0x00)

Running tests

Contributing

Author

License

vlydev / cs2-masked-inspect

Maintainers

Package info

Statistics

Security

README

Installation

Usage

Deserialize a CS2 inspect link

Serialize an item to a hex payload

Item with stickers and keychains

Gen codes

Generate a Steam inspect URL from parameters

Convert an ItemPreviewData to a gen code

Parse a gen code string

Convert an existing inspect link directly to a gen code

Validation

Validation rules

How the format works

Checksum algorithm

paintwear encoding

Proto field reference

CEconItemPreviewDataBlock

Sticker

Known test vectors

Vector 1 — Native CS2 link (XOR key 0xE3)

Vector 2 — Tool-generated link (key 0x00)

Running tests

Contributing

Author

License

`paintwear` encoding