itemmaingroup.bss

Binary layout, indexed condition semantics, byte coverage, and exact snapshot evidence for the itemmaingroup.bss decoder in calpheonlabs.

Investigation status

Status	Value
Evidence state	Reconciled
Coverage	100%
Iteration	4
Last reviewed	2026-07-31
Captures examined	Build 2938; `Paz/pad00000.meta` SHA-256 `b7eefe6059818f84c0545f10020fe93bd3bd5d0647e043120caf78726ccafe8f`
Primary bytes	667,876; SHA-256 `32b5c35dec689cb423f34dcddd8b116d3a06cb6876db031c4d0addd5c6488e9b`
Snapshot proof	16,227 rows / 18,633 entries / 197 conditions; normalized SHA-256 `b9527ac33f1ee7cc056b5f7a933b7190276c654a40be293743abefcdf8024fd3`
Decoder	`packages/scraper/src/tables/itemmaingroup.bss.ts`
Remaining blockers	None

See Decoder methodology. Subgroup identifiers are deferred joins to itemsubgroup.dbss; no companion bytes are loaded by this decoder.

Field ledger

Field/path	Offset and width	Representation	Claimed meaning	Physical confidence	Representation confidence	Semantic confidence	Evidence	Status
PABR signature	file `+0`, 4	checked `bytes(4).reserved()`	Table framing	Certain	Certain	Certain	Exact `PABR` bytes; byte-only framing is intentionally omitted	Closed
`rowCount`, `rows[]`	file `+4`, 4; variable rows	retained `u32`, counted array	Main-group count and rows	Certain	Certain	Certain	16,227 rows consume exactly to the condition dictionary	Closed
`rows[].groupId`	row `+0`, 4	`u32`	Main-group identifier	Certain	Certain	High	Stable unique identity referenced by NPC, shop, drop, and worker selectors	Closed
`rows[].field04`	row `+4`, 4	`u32`	Neutral row control	Certain	Certain	Unknown	Exact position and value retained; historical names do not agree exhaustively	Closed
`rows[].reserved08`, `reserved12`, `reserved17`, `reserved21`	row `+8..+12`, `+17..+24`	`bytes(n).reserved()`	Byte-only empty ranges	Certain	Certain	Unknown	Explicitly consumed and intentionally omitted	Closed
`rows[].marker13`	row `+13`, 4	retained bytes	Neutral marker	Certain	Certain	Unknown	Varies across rows and has no proven universal gameplay label	Closed
`rows[].entryCount`, `rows[].entries[]`	row `+25`, 4; then 10 each	retained `u32`, counted array	Reference count and list	Certain	Certain	Certain	18,633 entries derive every variable row width exactly	Closed
`entries[].reserved00`	entry `+0`, 4	`bytes(4).reserved()`	Byte-only empty prefix	Certain	Certain	Unknown	Explicitly consumed and intentionally omitted	Closed
`entries[].conditionIndex`	entry `+4`, 4	`u32`	Condition-array index	Certain	Certain	Certain	Every captured value resolves inside the 197-record dictionary	Closed
`entries[].subgroupId`	entry `+8`, 2	`u16`	Item-subgroup identifier	Certain	Certain	Certain	Exhaustive joins resolve through `itemsubgroup.dbss`	Closed
`trailer.conditionCount`, `conditions[]`	dictionary start, 4; variable	retained `u32`, counted array	Indexed condition dictionary	Certain	Certain	Certain	197 records consume exactly to the footer	Closed
`conditions[].marker`	condition `+0`, 1	retained `u8().is(1)`	Condition-record marker	Certain	Certain	Unknown	Uniform intrinsic marker and active validation	Closed
`conditions[].byteLength`	condition `+1`, 4	retained even `u32`	UTF-16 byte length	Certain	Certain	Certain	Retained independently and frames each string exactly	Closed
`conditions[].text`	condition `+5`, variable	UTF-16 text	Condition expression	Certain	Certain	High	Valid text indexed exhaustively by row entries	Closed
`footer.trailerOffset`	final `-8`, 4	retained `u32`	Condition-dictionary start	Certain	Certain	Certain	Agrees with count-derived row-region end; retained as informational footer data	Closed
`footer.reserved04`	final `-4`, 4	`bytes(4).reserved()`	Byte-only terminator	Certain	Certain	Unknown	Explicitly consumed and intentionally omitted without footer validation	Closed

Active assumptions

Findings

ID	Finding	Evidence	Schema/documentation impact	Status
IMG-01	Main-group rows and their condition dictionary are independently self-framed.	Row/entry counts, condition counts/lengths, and strict EOF consumption agree exactly.	Production decoding requires no offset companion or post-decode repair.	Resolved
IMG-02	`marker13` and `field04` do not have universal gameplay names.	Historical correlations are incomplete and the current capture preserves unexplained variation.	Neutral fields remain fully represented.	Resolved
IMG-03	Footer data is informational after the layout proof.	The stored pointer agrees with the captured row-region end.	`trailerOffset` is retained, while the footer has no runtime pointer check.	Resolved