The diagnostic code index

Every message koyu check returns, catalogued. There are 65 codes in 19 families: 49 errors and 16 warnings. This page shows which family a code belongs to and how heavy it is. The cause, a minimal reproduction, and the fix live on the family pages.

What check tells you stops at whether what is written is self-consistent as data. It says nothing about whether the building is usable — that is what koyu validate says, separately, with its 15 rules. The two are different types: check returns Diagnostic { code, severity } and validate returns Finding { rule, level }. Even the spellings differ on sight — a code is three letters plus two digits, a rule is chapter.rule (site.escape).

The human-facing check does not display codes. Get the code with --json before looking anything up here; the procedure is on Reading a diagnostic.

There are only two severities

severity	Meaning	check exit code	check --strict exit code
error	The composition does not stand up; no single shape can be made from what is written	1	1
warning	Suspect. It does stand up, and the shape is still determined	0	1

Severity is an invariant property of a code. The same code is never an error in one file and a warning in another. When the weight has to change, the existing code keeps its severity and a new code is minted.

Looking up by symptom

Symptom	Codes to look at
You wrote a boundary and were told the spaces "do not touch"	BND04
You placed a door or window and were told "there is more than one segment"	OPN05
You cannot get a window onto an external wall	OPN04 OPN05
You wrote a stair or a void and were told off	VRT01 VRT02 VRT03
You put a door on a stair and were told it "is not interpreted"	VRT05
You laid out spaces and were told "the regions overlap"	GEO02
The overlap appeared while subdividing a dwelling into rooms	GEO02 — the fix is not the layout
A path on a boundary is reported undefined	REF01
A floor finish written as an area will not pass	SEG01 SEG02
You thought you wrote a level and were told "its level cannot be determined"	SUF02
The floor-height arithmetic does not pass	HGT01 HGT02
No ceiling height or slab thickness written, and neither ceilings nor floors are generated	SUF01 SUF03
You wrote an attribute and it had no effect	ATT01 ATT02 ATT03
The site's figures do not agree	check does not say — koyu validate's site.escape / site.area do
The stair's going or slope is cramped	check does not say — koyu validate's stair.proportion / run.slope do
There is a hole in the envelope	check does not say — koyu validate's envelope.gap does
The file dies without a single line being read	SYN01

Every code

The order is the ledger's.

REF — references (1)

Code	severity	One line
REF01	error	References an undefined space

BND — boundaries (6)

Code	severity	One line
BND01	error	A boundary between a space and itself
BND02	error	A duplicate boundary
BND03	error	A wall boundary to a space on a different level
BND04	error	The spaces do not touch, so no boundary can be derived
BND05	warning	Edge-restricted and unrestricted boundaries coexist on one pair
BND06	warning	No edge remains on the perimeter, so the segment is of zero length

LVL — levels (1)

Code	severity	One line
LVL01	error	Two levels have the same z

GEO — overlapping regions (2)

Code	severity	One line
GEO01	error	The regions of one space overlap each other
GEO02	error	The regions of two spaces overlap

VRT — vertical boundaries (6)

Code	severity	One line
VRT01	error	A vertical boundary needs a region and a level on both sides
VRT02	error	A vertical boundary spans one step between adjacent levels
VRT03	error	The spaces of a vertical boundary do not overlap in plan
VRT04	warning	The space above a void boundary is not type:void
VRT05	warning	An opening on a vertical boundary is not interpreted
VRT06	warning	A seg on a vertical boundary is not interpreted

OPN — openings (8)

Code	severity	One line
OPN01	error	The wrong axis for hinge
OPN02	error	The openings overlap
OPN03	warning	An opening on an open boundary has no effect on passage
OPN04	error	There is no boundary segment on which to place the opening
OPN05	error	There is more than one boundary segment — ambiguous
OPN06	error	The opening is wider than the boundary segment
OPN07	error	The wrong axis for an explicit opening position
OPN08	error	An explicit opening position runs off the segment

SEG — uncounted subdivisions (8)

area (inside a room) is SEG01–SEG02; seg (along a boundary) is SEG03–SEG08.

Code	severity	One line
SEG01	error	An area on a space with no region
SEG02	warning	An area spills outside the region
SEG03	warning	A seg on an open boundary is not interpreted
SEG04	error	There is no boundary segment on which to place the seg
SEG05	error	There is more than one boundary segment for the seg — ambiguous
SEG06	error	The seg is wider than the boundary segment
SEG07	error	The wrong axis for an explicit seg position
SEG08	error	An explicit seg position runs off the segment

ZON — zones (2)

Code	severity	One line
ZON01	warning	There are no spaces beneath the zone
ZON02	warning	A space shares its path with a zone

HGT — the height invariant (2)

Code	severity	One line
HGT01	error	It collides into the floor above
HGT02	error	Insufficient coverage for a partial void

SUF — sufficiency (4)

Code	severity	One line
SUF01	error	The ceiling height cannot be determined; no ceiling and no roof can be generated
SUF02	error	The level cannot be determined; not one solid can be generated
SUF03	warning	The level has no slab, so not one floor is generated
SUF04	warning	A vertical-circulation declaration produces no shape at all

SIT — site outline (3)

Code	severity	One line
SIT01	error	The site shape has a duplicate vertex
SIT02	error	The site shape is self-intersecting
SIT04	warning	No zone corresponds to the polygon

SIT03 and SIT05 are retired numbers.

UID — identity (4)

Code	severity	One line
UID01	error	A uid cannot be a token of digits alone
UID02	error	A uid cannot contain whitespace
UID03	error	A duplicate uid
UID04	error	A duplicate name within one container

ATT — attributes (3)

Code	severity	One line
ATT01	error	The attribute takes a positive number
ATT02	error	The value is not in the ledger's vocabulary
ATT03	error	The key is not in the ledger and carries no namespace

DAY — daylight scope (1)

Code	severity	One line
DAY01	error	daylight is either 1 (in scope) or 0 (out of scope)

RUN — vertical circulation (4)

Code	severity	One line
RUN01	error	More than one vertical-circulation declaration on one space
RUN02	error	The value must be a direction of travel, N/E/S/W
RUN03	error	The region is not a single rectangle, or the level is unknown
RUN05	error	form is invalid, or the shape is not determined

RUN04, RUN06, RUN07 and RUN08 are retired numbers.

LIN — drawn lines (3)

Code	severity	One line
LIN01	error	The line does not separate the two spaces
LIN02	error	A vertical boundary cannot carry a line
LIN03	warning	The line cuts nothing

COL — columns (2)

Code	severity	One line
COL01	warning	Not one column stands for this declaration
COL02	warning	An earlier declaration already took the same intersections

VER — language-version acceptance (4)

Code	severity	One line
VER01	error	A koyu 0.1 file has a touching pair with no boundary declared
VER02	error	A koyu 0.3-or-earlier file has a habitable type with no daylight
VER03	error	A koyu 0.4-or-earlier file uses 0.5 vocabulary
VER04	error	A koyu 0.5-or-earlier file uses 1.0 vocabulary

SYN — syntax and composition (1)

Code	severity	One line
SYN01	error	A syntax or composition error

SYN01 is not a check of its own but the exception thrown while reading, copied into a single diagnostic. It appears only under check --json — without --json, check prints the exception as it is and exits 1.

Retired numbers

Numbers are never reused. Reusing one would make past output unreadable. Eleven are retired: six moved to koyu validate rules and four folded into the SUF family. What replaced what is on Retired diagnostic codes.

BND07 HGT03 HGT04 HGT05 RUN04 ENV01 RUN06 RUN07 RUN08 SIT03 SIT05

What a green check has not looked at

Green means the composition is self-consistent as data and a shape can be made from what is written. It says nothing about architectural validity. Two things in particular walk straight through it.

A sealed building. The default between touching spaces is a wall, and a wall is impassable without a door. A two-storey house with not one door written is green and completely sealed.

koyu doors <file> /L2/bed /out/road

If that answers "unreachable", the circulation is not connected. koyu validate's access.unreachable says the same thing as a violation.

Daylight. Not one window is needed to be green. koyu light <file> gives the 1/7 judgement per room, and koyu validate's daylight.ratio reports it as a violation.

How to call check and its flags is on koyu check; the validation surface is on koyu validate.