schema.toml

schema.toml is the database's schema: its views, fields, vocabularies, layers and access rules. mosaica build and mosaica check read the file that [build] schema in mosaica.toml names, schema.toml by default, or the one --config names. mosaica check --payloads prints the same declaration as the request bodies that declare it on a running service.

Every table refuses a key it does not know. Where a key is refused beside another, or needs another, its description says so.

Key	Type	Default	Description
sources	table of strings	not set	The files the declaration reads, as name = "path", each path relative to the directory the declaration is in. Every source key elsewhere names one of these. An empty name, an empty path and an absolute path are refused; --file NAME=PATH replaces a path from the command line.
defaults	table	not set	The source a block takes when it names none, and the view that orders internal ids.
shards	table	not set	The size of the shards the items are stored in.
view	array of tables	[]	Coordinate systems, each giving the items it holds a position on a map.
view_group	array of tables	[]	Sets of views that share every setting and differ by a key.
vocabulary	array of tables	[]	Named value sets, which category attributes draw on.
attribute	array of tables	[]	The columns each item carries.
layer	array of tables	[]	Annotation layers: named sets of artifacts, such as clusters or regions, drawn over views.

[defaults]

What a block takes when it names no source of its own. source reaches a [[view]] and an entity-scoped [[attribute]], and nothing else: a vocabulary, a layer, a view group and point_visibility with no source of their own read no file.

Key	Type	Default	Description
source	string	not set	A name in [sources], read by a [[view]] and an entity-scoped [[attribute]] that name no source. A name [sources] does not have is refused.
allocation_view	string	not set	The view whose map positions order the entity ids a build assigns to items with the same access labels. Where more than one view, counting each view of a group, reads points from a file, it is required; with one such view it is that view. A view of a group is named <group>:<key>, and a name that is not one of the build's views is refused.

[shards]

The size of the shards the items are stored in. Without this table the size is 4,026,531,840. PUT /control/shards declares the same table at a running service.

Key	Type	Default	Description
size	integer	required	The high water at which the shard taking new items seals and the next one opens. A positive integer; a size past 4,294,967,295, where the ids end, seals there. A build whose files create more items writes several shards. An edit of a sealed shard's item takes an id the shard has freed or one past its high water, so at a size at or past the end of the ids, the edits of a full shard are refused until a compaction frees ids.

[[view]]

One coordinate system: a position for each item it holds, the frame those positions are stored across, and who may see the view and each of its points.

Key	Type	Default	Description
name	string	required	The view's name, which a request names it by. ASCII letters, digits, _ and -, unique among views and view groups.
title	string	not set	A display title, served on /v1/meta as the view's display_name. Without one the view's name is served.
projection	string	"none"	How a longitude and latitude become a position on the map: web_mercator, equirectangular (also written plate_carree), gall_isographic, or none for coordinates that are not places on the Earth. It decides which spellings extent and fields take. Any other name is refused.
source	string	the value of [defaults].source	A name in [sources]: the file holding the view's points, one row per item. A view with no source is built with no rows, and takes its rows at a running service.
fields	table of strings	not set	Where the points file keeps each field, as field = "column". The fields are either x and y or morton and residual, or on a projected view lon and lat, and each attribute declared unique, whose column is its field or its name where this map does not move it. A field not named here is read from the column of its own name. A field the view does not have, both kinds of position, residual without morton, and fields where the view has no source are refused.
extent	string or table	required	The frame positions are stored across, as a 32-bit position on each axis. A point outside it is stored on its edge, and a build reports how many points that moved but never refuses the frame. The spellings are under [view.extent].
point_visibility	table	required	Where each point's access label comes from: keys under [view.point_visibility].
visibility	string or array of strings	"public"	The access label a viewer must satisfy to reach the view, or a list of labels of which they must satisfy one. Each label is an access expression, such as finance&(eu|uk). public alone admits every viewer. An empty list, an empty label, inherited, public beside another label, and a label that is not an access expression are refused.

[view.extent]

extent is the word "auto" or a table. A view with no projection takes four spellings, in the units of its own coordinates:

extent = "auto"                           # the same as { auto = true, margin = 0.01 }
extent = { auto = true, margin = 0.25 }   # a square fitted to the data, plus margin each side
extent = { min = -25.0, max = 25.0 }      # one range for both axes
extent = { x = [-18, 19], y = [-22, 24] } # a range for each axis

A projected view takes auto and a box in degrees, which it widens to the smallest aligned square that contains it, or a box in the coordinates the projection produces, taken as written. The last is the frame /v1/meta reports for a view, which gives a new view another's frame:

extent = "auto"                                     # the data's own longitude and latitude
extent = { lon = [-8.6, 1.8], lat = [49.9, 60.9] }  # a box in degrees
extent = { x = [0.5, 0.75], y = [0.25, 0.5] }       # a box in the projected frame

auto reads the view's points to fit the frame, so it is refused where the points source holds no rows. Any other word, an empty table, half a box, a number that is not finite, a box in degrees on a view with no projection, and auto as a table on a projected view are refused.

Key	Type	Default	Description
auto	boolean	not set	true fits the frame to the points the build reads. false is refused, and so is auto beside min, max, x or y. A projected view writes extent = "auto" instead.
margin	number	0.01	Space added to each side of an auto frame, as a fraction of the data's span. Finite and at least 0. Refused without auto = true.
min	number	not set	The low end of both axes, beside max.
max	number	not set	The high end of both axes, beside min. It must be above min.
x	array of 2 numbers	not set	The x axis as [low, high], beside y, with high above low.
y	array of 2 numbers	not set	The y axis as [low, high], beside x, with high above low.
lon	array of 2 numbers	not set	A projected view's longitudes as [west, east], in degrees within ±180, beside lat. A box crossing the antimeridian, with west above east, is refused.
lat	array of 2 numbers	not set	A projected view's latitudes as [south, north], in degrees within ±90, beside lon, with north not below south.

[view.point_visibility]

Where each point's access label comes from. A label is an access expression, such as secret&(team_a|team_b), and a viewer sees a point when their terms satisfy one of its labels. Write field or source, not both, and at least one of the three keys.

Key	Type	Default	Description
field	string	not set	A column of the view's points file holding each point's access label, as a string or a list of strings. A null or an empty list is no label. An empty name is refused.
source	string	not set	A name in [sources]: a file of an integer term_id beside the column of at least one attribute declared unique, which names the point, one row per point and access term. If one view of a build reads labels this way, every view must, from the same file.
default	string	not set	The label a point with none of its own takes: public for every viewer, or an access expression. inherited is refused. Without it, a point with no label is refused, at a build and at /control/ingest alike.

[[view_group]]

A set of views that share every setting and differ by a key, and by the metadata each view carries. A view of the group is addressed <group>:<key>. The roster, which says what the views are, takes one of three forms:

• [[view_group.view]] blocks, one per view, each naming its own points file. The group names no source.
• A [view_group.views] file with one row per view, beside a group source holding every view's points in rows that name their view in a view column.
• Neither: the group's source holds every view's points, and the views are the distinct values of its view column. They carry no metadata.

Writing both rosters is refused. [defaults].source does not reach a group, so a build refuses a group with neither a source nor [[view_group.view]] blocks.

Key	Type	Default	Description
name	string	required	The group's name, the first half of each of its views' ids. ASCII letters, digits, _ and -, unique among views and view groups.
title	string	not set	A display title, served on /v1/meta.
projection	string	"none"	As on [[view]].
source	string	not set	A name in [sources]: the file holding every view's points, one row per item and view. Required with [view_group.views] and refused beside [[view_group.view]] blocks.
fields	table of strings	not set	Where the group's source keeps each field: as on [[view]], and view, the column naming each row's view. Refused on a group with no source.
extent	string or table	required	As on [[view]]: one frame for every view of the group.
point_visibility	table	required	As on [[view]], for every view of the group.
visibility	string or array of strings	"public"	As on [[view]], for every view of the group. A view of the group may narrow it with a visibility of its own.
members	string	not set	Another group's name: this group's views are that group's, and its own source holds their points. Through this group a view is reached by this group's visibility alone; a gate the owning group's roster gives the view does not apply here, and the points keep their own labels. The group named may not itself name members, and a roster or metadata beside members is refused.
metadata	table	not set	The values each view carries, served with it on /v1/meta: name = "type" over the [[attribute]] types, or name = { type = "category", vocabulary = "<name>" }, whose value is a key taken as an attribute's category value is: a closed vocabulary refuses a key it does not list, and an open one adds it. Every view must carry every name. key, source, visibility and the group's view column are refused as names, and so is metadata on a group whose views are minted from its source with no roster, or one that names members.
view	array of tables	[]	The roster as one block per view: keys under [[view_group.view]].
views	table	not set	The roster as a file: keys under [view_group.views].

[[view_group.view]]

One view of a group, written in the declaration. Beside these keys the block takes one for each name the group's metadata declares, holding a value of the declared type, and every view carries every name. A timestamp_us value is a date, such as 2026-04-01, which is midnight UTC; a date-time with an offset, such as 2026-04-01T09:30:00Z, with at most six fractional-second digits and a space allowed for the T; or microseconds since the Unix epoch, as an integer or a string of digits. Either date form may also be written as a string. A date-time with no offset is refused. A float may be written as an integer, and nan and inf are refused. An integer outside its type's range is refused. A group-level key, such as extent or projection, is refused, and so is any other key.

Key	Type	Default	Description
key	string	required	The view's key: its id is <group>:<key>. ASCII letters, digits, _ and -, and no two views of the group may share one.
source	string	not set	A name in [sources]: the file holding this view's points. A view with none is built with no rows.
visibility	string or array of strings	not set	The label, or list of labels of which a viewer must hold one, to reach this view as well as the group, in this group only. Without it, or with public alone, the group's visibility is the view's only gate.

[view_group.views]

The roster as a file of one row per view, beside the group's source. Its columns are key, visibility, and one for each metadata name.

Key	Type	Default	Description
source	string	required	A name in [sources]: the roster file.
fields	table of strings	not set	Where the roster file keeps key, visibility and each metadata name, as field = "column".

[[vocabulary]]

A named set of values that category attributes and category metadata draw on. Each value is stored as an integer code: pinned where the declaration or its file writes one, and otherwise drawn at random, which a rebuild does again.

Key	Type	Default	Description
name	string	required	The vocabulary's name. ASCII letters, digits, _ and -, unique among vocabularies.
title	string	not set	A display title. Not built yet: the title is accepted and not published.
width	string	required	The width codes are stored at: u8, u16 or u32, whose largest codes are 255, 65,535 and 4,294,967,295.
value_set	string	required	closed refuses a value the vocabulary does not hold, at a build and at ingest. open gives such a value a new code.
visibility	string	required	public shows every viewer every value. derived shows each viewer only the values carried by points they can see.
source	string	not set	A name in [sources]: a file of values, with a key column and optional code and title columns. A value with no code is drawn one. Refused beside values.
fields	table of strings	not set	Where the values file keeps key, code and title, as field = "column".
values	array of strings, or table of integers	not set	The values written here: an array of keys, each drawn a code, or a table of key = code, which pins them. A code is from 1 to the width's largest, since 0 means no value. Two values at one code, a code also reserved, an empty key and a key given twice are refused, and so is values beside source.
reserved	array of integers	not set	Retired codes, from 1 to the width's largest, which no value may hold and no draw picks.

[[attribute]]

A column each item carries. render and index decide where its value is kept, and may be set together. render = true stores the value beside each point's position, so it travels with every point a viewport returns and can colour the map. index = true builds an index that filters and searches by it. With neither, the value is kept in the item's record and read when the item is opened.

Key	Type	Default	Description
name	string	required	The column's name, which filters and /v1/categories/{column} use. ASCII letters, digits, _ and -, unique among attributes. mosaica_id, residual, x, y, access, node_id, record, all_of, any_of, none_of, region, member_of and highlighted are refused.
title	string	not set	A display title. Not built yet: the title is accepted and not published.
field	string	the attribute's name	The column of the source file holding the values. An empty name is refused.
source	string	the value of [defaults].source	A name in [sources]: the file the values are read from. A file other than a view's points names the item each row belongs to by the columns of the attributes declared unique. An entity-scoped attribute with no source here or in [defaults] is built with no values, and a build whose views create items refuses it. A group-scoped attribute with none reads each view's own points file, and [defaults] does not reach it.
type	string	required	The type of value the column holds, one of the types below.
vocabulary	string	not set	The [[vocabulary]] a category draws on. Required on a category, refused on every other type, and a name no [[vocabulary]] declares is refused.
render	boolean	false	Store the value beside each point's position. Refused on keyword and text.
index	boolean	false	Build an index that filters and searches by the value. A group-scoped text column needs it.
unique	boolean	false	No two items may hold one value, and a row carrying a value names the item holding it. Every file the build reads names items by the columns of these attributes where it carries them. A points row naming no item creates one, and a row of any other file naming none is refused. A later row naming an item an earlier row of its file names, or giving a second item a value, is refused. A build reports the rows it refuses; an ingest giving an item a value another item holds is refused. eq and in filters on the column are answered from its index, with or without index = true; without it, they are the only filters it takes. Applies to keyword, integer and timestamp_us columns scoped to the entity. A null is no value, so any number of items may hold one.
scope	string or table	"entity"	"entity": one value per item, the same under every view. { group = "<name>" }: one value per item and view of that group, which must own its views rather than name members.
fields	table of strings	not set	Where this attribute's source keeps the fields that name each row's item, as field = "column": each attribute declared unique, under its own name, where the source calls its column something else; and on a group-scoped attribute, view, the column saying which view each row's value is for, view if absent. Any other field, and fields on an attribute with no source, is refused.
analyser	string	"unicode"	The analyser that turns a text column into search terms. This build has unicode, and refuses any other name. Refused on every other type.

The types type takes:

Type	Holds
bool	true or false
u8	an integer from 0 to 255
u16	an integer from 0 to 65,535
u32	an integer from 0 to 4,294,967,295
u64	an integer from 0 to 2^64 - 1
i8	an integer from -128 to 127
i16	an integer from -32,768 to 32,767
i32	a signed 32-bit integer
i64	a signed 64-bit integer
f32	a 32-bit floating-point number
f64	a 64-bit floating-point number
timestamp_us	an instant, stored as microseconds since the Unix epoch
keyword	a short string matched exactly, such as an identifier or a hostname. Refused with render = true
text	prose, searched by the terms its analyser produces. Refused with render = true
category	a value of the vocabulary vocabulary names, stored as its code at the vocabulary's width

[[layer]]

An annotation layer: a named set of artifacts, such as clusters or regions, drawn over one or more views. An artifact's members are the items it contains. Three keys decide who may learn that an artifact exists, and none has a default: visibility, artifact_visibility and require_member_visibility.

A layer's artifacts come from its own source file, from [[layer.artifacts]] blocks, or from neither, in which case the layer is declared empty and filled through the control plane. [defaults].source does not reach a layer.

Key	Type	Default	Description
name	string	required	The layer's name. Unique among layers, not empty, and not all in any case, which a viewport request writes for every layer.
title	string	not set	A display title, served on /v1/meta.
views	array of strings	required	The views the layer is drawn on. A view group's name draws it on every view of the group, and on each view created in the group later. A name no [[view]] or [[view_group]] declares, and a name given twice, are refused.
scope	string or table	"entity"	"entity": one set of artifacts drawn on every view the layer names. { group = "<name>" }: a set for each view of that group, each artifact naming its view in the view field, and views may name only that group's views.
source	string	not set	A name in [sources]: the artifacts file, one row per artifact. Refused beside [[layer.artifacts]].
fields	table of strings	not set	Where the artifacts file keeps each field, as field = "column". The fields are key; members or excluding, on an enumerated layer; contents, where the layer supplies content; parent, under a nested, dag or tiered hierarchy; attached_layer and attached_key, where it has depends_on; view, on a group-scoped layer; space, where it has a shape or polygon content; and the shape's own fields: min_x, min_y, max_x and max_y for a bbox, cx, cy and r for a circle, cx, cy, a, b and angle for an ellipse, and geometry, as WKB, for a polygon. level and attached_level are read under their own names. A members or excluding column is a list of structs, each struct one member, with a field for each attribute declared unique that names it, under the attribute's column. A field the layer does not declare, both members and excluding, and fields beside [[layer.artifacts]] are refused.
artifacts	array of tables	not set	Artifacts written in the declaration: keys under [[layer.artifacts]]. Refused beside source.
membership	string or table	required	How an artifact's members are found. "enumerated": a stored set per artifact. "spatial": the points inside the artifact's shape. { attribute = "<name>" }: one artifact per value of that attribute, which must have index = true and a category, u8, u16 or u32 type.
members	table	not set	Members as a file of their own, one row per artifact and member: keys under [layer.members]. Only on an enumerated layer, and refused beside a members or excluding field.
value_set	string	"closed"	"closed": the layer's artifacts are the ones its source or [[layer.artifacts]] declare, and a member row naming another is refused. "open": a member row naming a new key creates an artifact with that key. Any other value is refused.
hierarchy	table	required	How the layer's artifacts relate to each other: keys under [layer.hierarchy].
levels	array of tables	[]	The layer's levels: keys under [[layer.levels]]. Required under a stacked or tiered hierarchy, and refused under nested and dag and on an attribute membership.
layout	string	chosen by the server, again at each compaction	How the layer is stored for serving. "rows": a set of rows per artifact. "column": one artifact per row, for a level whose artifacts do not overlap. "list": a list of artifacts per row. A layer declared "column" whose artifacts overlap is served as "rows". Without this key, a flat, stacked or tiered layer with an enumerated membership is stored as "column" where a level's artifacts do not overlap and "list" where they do; any other layer is stored as "rows", unless a level holds at least 1,000 artifacts and a quarter of them are spread too widely for the map's index, when it takes "column" or "list" the same way. Refused on an attribute membership.
visibility	string	required	The access label a viewer must hold to learn that the layer exists, or public for every viewer. An empty label and inherited are refused.
artifact_visibility	table	required	What gates each artifact beyond visibility: keys under [layer.artifact_visibility].
require_member_visibility	string or table	required	How much of an artifact's membership a viewer must see for the artifact to be served: "all", "any", { count = n } with n at least 1, { fraction = p } with p a float above 0 and at most 1, or "none" for no such rule. "all" and fraction are refused on a spatial or attribute membership.
withdraw_on_member_deletion	boolean	false	Only false is accepted. Not built yet: withdrawing an artifact when one of its members is deleted. A deleted member leaves the artifact, and its computed content is recomputed from the members left.
depends_on	array of strings	[]	Layers whose artifacts this layer's artifacts attach to, through attached_layer and attached_key. Each must be declared before this one. Naming the layer itself is refused, and so is depends_on on an attribute membership.
content	table	not set	What each artifact carries besides its members: keys under [layer.content].
shape	table	not set	The kind of shape each artifact of a spatial layer carries: keys under [layer.shape]. Refused on any other membership. A spatial layer without one holds no artifacts.
default_space	string	"view"	The space a row of the source file writes its geometry in when it names none: "view", the view's own coordinates, or "wgs84", longitude and latitude in degrees, which every view the layer is drawn on must have a projection to take. Refused on a layer with neither a shape nor polygon content. A [[layer.artifacts]] row without a space is in "view" whatever this says.
labels	table	not set	A layer of labels for this layer's artifacts, written here: keys under [layer.labels].

[[layer.artifacts]]

One artifact written in the declaration, for a layer a person authors rather than a pipeline produces. Its keys are the artifacts file's fields under their own names, and a layer written this way builds the same bundle as the same rows in a file. A shape is written in the key its layer's [layer.shape] kind names.

Key	Type	Default	Description
key	string	required	The artifact's key, which parent and attached_key name it by.
level	integer	0	The level the artifact is at: 0 on a layer with no levels.
members	table of arrays of strings or integers	not set	The members, as a table of columns keyed by the names of attributes declared unique, each an array of one length, the entries at one position naming one member: members = { geonameid = [2643743, 2988507] }. A value is a string for a keyword field, and an integer or a string of its decimal digits for an integer one, the string holding a value TOML cannot write as an integer, such as a u64 from 2^63. A member naming no item is refused and reported, and the artifact holds the rest. Only on an enumerated layer, and refused beside excluding.
excluding	table of arrays of strings or integers	not set	The members by exclusion: the items the artifact leaves out, written as members is, which the build turns into members. Only on an enumerated layer, and refused beside members.
contents	array of arrays of strings	[]	The artifact's content, best first: one array per rank, holding a value for each [[layer.content.supplied]] entry in order.
bbox	array of numbers	not set	A bbox layer's shape: [min_x, min_y, max_x, max_y].
circle	array of numbers	not set	A circle layer's shape: [cx, cy, r].
ellipse	array of numbers	not set	An ellipse layer's shape: [cx, cy, a, b, angle], with a and b its semi-axes and angle its rotation in degrees.
wkt	string	not set	A polygon layer's shape, as well-known text: "POLYGON ((…))".
space	string	"view"	The space the row's geometry is written in: "view" or "wgs84", which every view the layer is drawn on must have a projection to take. It governs the shape and any polygon content.
parent	string or array of strings	[]	The artifact's parents, by key: one under a nested or tiered hierarchy, and any number under dag.
attached_layer	string	not set	The layer this artifact attaches to, one that depends_on names.
attached_level	integer	0	The level of the artifact this one attaches to.
attached_key	string	not set	The key of the artifact this one attaches to.
access	string or array of strings	not set	The artifact's own access labels, on a layer whose artifact_visibility names a field: one label, a list, or [] for none of its own. Such a layer refuses a row without it.

[layer.members]

An enumerated layer's members as a file of their own, one row per artifact and member, for a membership too large for one field of the artifacts file. Under value_set = "closed", a members file needs the layer's own source or [[layer.artifacts]] for its rows to name.

Key	Type	Default	Description
source	string	not set	A name in [sources]: the members file.
fields	table of strings	not set	Where the members file keeps each field, as field = "column": key, the artifact's key; each attribute declared unique, under its own name, whose values name the member, such as fields = { id = "entity" }; and rank, where the layer supplies content, the rank in contents whose content was made from this member.

[layer.hierarchy]

How a layer's artifacts relate to each other, written as hierarchy = { kind = "flat" }.

Key	Type	Default	Description
kind	string	required	flat: one population. nested: a tree, each artifact naming its parent, every artifact at level 0. dag: the same with any number of parents. stacked: independent analyses, one per level. tiered: levels, each artifact naming a parent at a coarser level. An attribute membership takes flat alone.
prune_children	boolean	false	Serve only the deepest artifact that passes along each branch.

[[layer.levels]]

One level of a stacked or tiered layer. Levels are numbered from 0 with none repeated or missing.

Key	Type	Default	Description
level	integer	required	The level's number, which an artifact names in its level.
title	string	not set	A display title, served on /v1/meta.
zoom	array of 2 integers	every zoom	The zoom levels the level is served at, [low, high] inclusive. A request naming no levels is answered with the levels whose range covers its zoom. A range with low above high, or starting past 16, is refused.

[layer.artifact_visibility]

What gates each artifact beyond the layer's own visibility. Written as artifact_visibility = { default = "inherited" }, or with a field naming each artifact's own labels.

Key	Type	Default	Description
field	string	not set	The field holding each artifact's own access labels: a column of the artifacts file, or access on a [[layer.artifacts]] row. Naming it declares that artifacts carry labels of their own. An empty name is refused, and so is field on an attribute membership.
default	string	required	The label an artifact with none of its own takes: an access label, public for every viewer, or inherited, which leaves the layer's visibility as the artifact's only gate. An empty label is refused.

[layer.content]

What each artifact carries besides its members.

Key	Type	Default	Description
computed	array of strings	[]	Properties the server computes from the members each viewer can see: centroid, box and hull. Any other name, a name given twice, and computed on an attribute membership are refused, and so is hull beside a shape or polygon content, since an artifact draws one shape.
supplied	array of tables	[]	Content the artifacts carry, one entry per kind: keys under [[layer.content.supplied]].

[[layer.content.supplied]]

One kind of content each artifact carries, in its contents. Refused on an attribute membership.

Key	Type	Default	Description
name	string	required	The content's name, unique within the layer.
type	string	required	text, polygon, extent or point, published on /v1/meta so a client knows how to draw it. polygon content is the artifact's drawn shape, so it is refused beside a hull or a [layer.shape].
require_member_visibility	string	required	"all": content made from the members, served only to a viewer who can see every member it was made from. "inherited": content true whatever the members, such as a name a person wrote, gated by the artifact alone.

[layer.shape]

The kind of shape each artifact of a spatial layer carries. An artifact's members are the points inside its shape.

Key	Type	Default	Description
kind	string	required	bbox, circle, ellipse or polygon.
depth	any	not set	Refused: every shape kind is exact, so a shape has no depth.

[layer.labels]

A layer of labels for the artifacts of the layer it is written in, such as a name for each cluster. It builds the same bundle as a second [[layer]] written after this one, with the same views and scope, hierarchy = { kind = "flat" }, depends_on naming this layer, and one [[layer.content.supplied]] entry named for the label layer, of type type, at the requirement [layer.labels.content] states. Each label names the artifact it labels with attached_layer and attached_key. A label layer that needs any other key is written out as a [[layer]].

Key	Type	Default	Description
name	string	required	The label layer's name, as on [[layer]].
title	string	not set	A display title, served on /v1/meta.
source	string	not set	As on [[layer]]: the labels file, one row per label.
fields	table of strings	not set	As on [[layer]].
members	table	not set	As [layer.members]: the members each label was made from.
type	string	required	The kind of content each label is: text, polygon, extent or point.
membership	string or table	required	As on [[layer]].
require_member_visibility	string or table	required	As on [[layer]]: how much of a label's membership a viewer must see for the label to be served.
content	table	required	The requirement on each label's content: keys under [layer.labels.content].
artifact_visibility	table	required	As on [[layer]].
visibility	string	the visibility of the layer it is written in	As on [[layer]].

[layer.labels.content]

The requirement on each label's content, which becomes its content entry's require_member_visibility.

Key	Type	Default	Description
require_member_visibility	string	required	"all" where the label was made from the items it names, so a viewer reads it only when they can see all of them. "inherited" where it is true whatever they are, such as a name a person wrote.