# Query parameters

Parameters for `GET /v1/map` and `GET /v1/map.{ext}`. The same options exist in the JSON body of `POST /v1/map` (see [Request body](/docs/reference/request-body.md)).

## Area and framing

What the map is about and how it is framed. All of these are optional, but a map needs an `area`, `bounds`, `center`+`zoom`, a route, a shape or at least one point.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-area"></a>`area` | string \| object | — | The area to frame and highlight. Ambiguous names return 409 with candidates. Name, `iso:CZ`, `iso:CZ-72`, `osm:r51684` or `wikidata:Q213`. Country-level areas fall back to Natural Earth when the OSM import does not cover them (`area=Japan`, `iso:IT`); regions and cities need the OSM import. | `area=Czechia` |
| <a id="param-level"></a>`level` | integer, 1–11 | — | Only match areas at this OSM admin level (2 = country; regions and municipalities vary by country). Narrows a name lookup (turns `area` into `{query, level}`). | `level=8` |
| <a id="param-country"></a>`country` | string | — | Only match areas inside this ISO 3166-1 alpha-2 country. Narrows a name lookup. | `country=CZ` |
| <a id="param-bounds"></a>`bounds` | string | — | Explicit frame `[west, south, east, north]`; overrides automatic framing. Cannot be combined with `center`/`zoom`. `west,south,east,north`. | `bounds=12.09,48.55,18.86,51.06` |
| <a id="param-center"></a>`center` | string | — | Center of the map. With `zoom`, this is an exact camera (as in other static map APIs) and nothing else affects the frame. Without `zoom`, the zoom is chosen so the area, routes, shapes and points fit around this center. `lat,lon` (the same order as `poi`, `from` and `to`). | `center=50.08,14.42` |
| <a id="param-zoom"></a>`zoom` | number, 0–22 | — | Zoom level, 0 (whole world) to 22, in the usual web-map zoom units (512 px tiles, as MapLibre and Mapbox GL: at zoom z the world is 512·2^z CSS px wide). With `center`, an exact camera; without `center`, the map is centered on the content at this zoom. Not available with the globe projection. Fractional zooms work (`5.5`). | `zoom=12` |
| <a id="param-padding"></a>`padding` | number, 0–0.45 | `0.04` | Space around the framed content as a fraction of the image size. | `padding=0.04` |
| <a id="param-projection"></a>`projection` | `mercator` \| `globe` \| `auto` | `mercator` | Map projection. `mercator` is the usual flat web map. `globe` draws an orthographic globe, which keeps continent-spanning routes and high latitudes true to shape; the content must fit on one hemisphere (within 85° of the view center), and neighbor labels are not available. `auto` picks the globe when the content spans more than 50° or Mercator would stretch it more than 2.5× between its lowest and highest latitude, else Mercator. `mercator` (default), `globe` or `auto`. | `projection=globe` |
| <a id="param-globeview"></a>`globeview` | `full` \| `fit` | `full` | How much of the globe to show. `full` (default): the whole globe, centered on your content, with space around it; recognizable at a glance as a globe. `fit`: zoomed in until the content fills the image; a larger scale with more detail along the route, but only part of the globe is visible. `full` (default) or `fit`. | `globeview=fit` |

## Points

Labeled markers. Repeat `poi` for each point; options go after the location, separated by `|`.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-poi"></a>`poi` | string (repeatable) | — | Points with markers and labels (up to 50). `lat,lon` or `place:Name`, followed by `\|option:value` pairs (see POI options). Repeat for more points. | `poi=49.13,17.33\|label:Chřiby\|marker:triangle` |

## Shapes

Your own lines and polygons. Repeat `shape` for each one (drawn in order, later on top); style options come first as `key:value|`, the geometry is always the last part. See Shape options below.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-shape"></a>`shape` | string (repeatable) | — | Extra lines and polygons, drawn in order (later ones on top). Up to 50; in GET, repeat `shape`. Style options as `key:value\|`, then the geometry as the last part: `line:lat,lon;…`, `polygon:lat,lon;…`, `polyline:<encoded>`, `polyline6:<encoded>` or `geojson:<json>`. Repeat for more shapes (drawn in order). See Shape options. | `shape=color:#d01c1c\|width:3\|line:50.08,14.42;49.19,16.61` |

## Route

One route per GET request (use POST for several). Give `from` and `to`, or a `polyline`.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-from"></a>`from` | string | — | Start point when the server should compute the line. `lat,lon` or `place:Name`. A route needs `from`+`to` or `polyline`. | `from=40.4168,-3.7038` |
| <a id="param-to"></a>`to` | string | — | Finish point when the server should compute the line. | `to=place:Sevilla` |
| <a id="param-via"></a>`via` | string (repeatable) | — | Points the route must pass through, in order. | `via=38.98,-3.93` |
| <a id="param-profile"></a>`profile` | `car` \| `bike` \| `foot` \| `straight` \| `geodesic` | `geodesic` | How endpoints are connected: routed by `car`/`bike`/`foot` (needs a routing engine on the server or your `X-Routing-Key`), or locally as `straight` segments or `geodesic` great-circle arcs. The default `geodesic` always works (no routing engine, key or plan feature needed) and is the true shortest path, so it suits flights and locator maps; ask for `car`/`bike`/`foot` explicitly for roads. | `profile=straight` |
| <a id="param-polyline"></a>`polyline` | string | — | The line as an encoded polyline (Google algorithm). URL-encode it (polylines can contain `\|`, `?` and `\`). | ``polyline=_p~iF~ps\|U_ulLnnqC_mqNvxq`@`` |
| <a id="param-polylineprecision"></a>`polylineprecision` | `5` \| `6` | `5` | Polyline precision: 5 (Google) or 6 (Valhalla/OSRM). | `polylineprecision=6` |
| <a id="param-routeprovider"></a>`routeprovider` | `valhalla` \| `openrouteservice` \| `graphhopper` | — | Routing provider (default: the server's). openrouteservice and GraphHopper need a key (server-side or `X-Routing-Key`). | `routeprovider=valhalla` |
| <a id="param-routecolor"></a>`routecolor` | string | `#d01c1c` | Color of the route line. | `routecolor=#d01c1c` |
| <a id="param-routewidth"></a>`routewidth` | number, 0.5–20 | `3` | Line width in px. | `routewidth=3` |
| <a id="param-routecasing"></a>`routecasing` | string | `#ffffff` | Outline drawn under the line so it reads on busy basemaps. | `routecasing=#ffffff` |
| <a id="param-routedash"></a>`routedash` | string | — | Dash pattern in line widths, e.g. `[2, 1.5]`. Comma-separated. | `routedash=2,1.5` |
| <a id="param-routeopacity"></a>`routeopacity` | number, 0–1 | `1` | Line opacity. | `routeopacity=0.9` |
| <a id="param-fromlabel"></a>`fromlabel` | string | — | Label at this end (default: the place name, if the end was given as a place). | `fromlabel=Madrid` |
| <a id="param-tolabel"></a>`tolabel` | string | — | Label at this end (default: the place name, if the end was given as a place). | `tolabel=Sevilla` |
| <a id="param-frommarker"></a>`frommarker` | `pin` \| `dot` \| `ring` \| `flag` \| `triangle` \| `circle` \| `square` \| `star` \| `diamond` | — | Marker preset. Defaults depend on the role: plain point → `pin`, route start → `ring`, route finish → `flag`. | `frommarker=dot` |
| <a id="param-tomarker"></a>`tomarker` | `pin` \| `dot` \| `ring` \| `flag` \| `triangle` \| `circle` \| `square` \| `star` \| `diamond` | — | Marker preset. Defaults depend on the role: plain point → `pin`, route start → `ring`, route finish → `flag`. | `tomarker=pin` |
| <a id="param-showfrom"></a>`showfrom` | boolean | `true` | `false` hides the marker and label for this end. | `showfrom=false` |
| <a id="param-showto"></a>`showto` | boolean | `true` | `false` hides the marker and label for this end. | `showto=false` |

## Image

Size, format and attribution of the output image.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-w"></a>`w`<br>alias `width` | integer, 64–2048 | `600` | Image width in CSS px (the output is width × `scale` pixels). | `w=468` |
| <a id="param-h"></a>`h`<br>alias `height` | integer, 64–2048 | `400` | Image height in CSS px, including the title band if any. | `h=280` |
| <a id="param-scale"></a>`scale` | integer, 1–3 | `1` | Pixel ratio for high-DPI output (2 = retina). | `scale=2` |
| <a id="param-format"></a>`format` | `png` \| `jpeg` \| `webp` | `png` | Image format (GET can also use the path extension: /v1/map.png, .jpg, .webp). Or use the path extension: `/v1/map.webp`. | `format=webp` |
| <a id="param-quality"></a>`quality` | integer, 1–100 | `90` | JPEG/WebP quality. | `quality=85` |
| <a id="param-attribution"></a>`attribution` | `bottom-right` \| `bottom-left` \| `top-right` \| `top-left` \| `none` | `bottom-right` | Corner for the data attribution, or `none` to leave it off the image. The data licenses (OpenStreetMap ODbL, and Natural Earth/terrain credits where used) still require it: with `none` you must show the attribution next to the image yourself. The text to show is returned in the `X-Attribution` response header. A corner, or `none`/`false` to leave it off (you must then show it next to the image; see `X-Attribution`). | `attribution=bottom-left` |
| <a id="param-logo"></a>`logo` | `bottom-right` \| `bottom-left` \| `top-right` \| `top-left` \| `none` | `bottom-left` | Corner for the small `wherebox.dev` mark (9.5 px text), or `none` to hide it. Hiding the logo requires a logo-removal license (see the Fair use guide); it is not enforced technically. A corner, or `none`/`false` to hide it (needs a logo-removal license). | `logo=bottom-right` |

## Basemap

The map underneath: a built-in preset or your own MapLibre style.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-preset"></a>`preset` | `locator-relief` \| `light` \| `dark` \| `none` | `locator-relief` | Built-in basemap: shaded relief (Wikipedia locator style), light, dark, or `none`: no map at all, only a plain `background` color with your area outline, shapes, routes and points on it (the "outline of Texas with a star" look). No key needed. | `preset=dark` |
| <a id="param-style"></a>`style` | string | — | Any MapLibre style.json URL; overrides `preset`. `{key}` in the URL is replaced with `providerKey`. URL-encode it. | `style=https://api.maptiler.com/maps/streets-v2/style.json?key={key}` |
| <a id="param-background"></a>`background`<br>alias `bg` | `transparent` | — | Background color for preset `none` (default white): any hex color, or `transparent` for a PNG/WebP with a transparent background that sits on any page. Labels, outline and attribution switch to light colors on a dark background. Only valid with preset `none`; `transparent` does not work with JPEG. With `preset=none`. URL-encode `#` as `%23`; `transparent` for PNG/WebP. | `background=#000000` |
| <a id="param-key"></a>`key` | string | — | Key for a commercial style (prefer the `X-Provider-Key` header so it stays out of URLs). Prefer the `X-Provider-Key` header so the key stays out of URLs and logs. | `key=your-provider-key` |

## Highlight

How the area stands out. Unset values use the defaults of the chosen basemap preset.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-fade"></a>`fade` | number, 0–1 | `0.45` (varies by preset) | How much the surroundings are washed out: 0 = not at all, 1 = fully covered. | `fade=0.6` |
| <a id="param-fadecolor"></a>`fadecolor` | string | `#ffffff` (varies by preset) | Color the surroundings fade towards. URL-encode `#` as `%23`. | `fadecolor=#ffffff` |
| <a id="param-outline"></a>`outline` | string | `#555555` (varies by preset) | Area outline color. | `outline=#555555` |
| <a id="param-outlinewidth"></a>`outlinewidth` | number, 0–10 | `1.1` (varies by preset) | Area outline width in px; 0 = none. | `outlinewidth=2` |
| <a id="param-tint"></a>`tint` | string | — | Optional color tint drawn over the area. | `tint=#d03030` |
| <a id="param-tintopacity"></a>`tintopacity` | number, 0–1 | `0.15` (varies by preset) | Opacity of `tint`. | `tintopacity=0.12` |
| <a id="param-subdivisions"></a>`subdivisions` | boolean \| string \| integer, `auto`, 3–11 | `auto` (varies by preset) | Inner admin borders: `auto` draws the next level that splits the area, a number forces that admin level, `false` hides them. `auto`, `false`, or an admin level number. | `subdivisions=auto` |
| <a id="param-desaturate"></a>`desaturate` | number, 0–1 | `0` (varies by preset) | Outside the area: 0 = full color, 1 = grayscale (applied on top of `fade`). | `desaturate=0.8` |
| <a id="param-blur"></a>`blur` | number, 0–20 | `0` (varies by preset) | Outside the area: blur radius in CSS px; 0 = sharp. | `blur=1.5` |
| <a id="param-subarea"></a>`subarea` | string \| object | — | A second, smaller area highlighted inside the framed one (e.g. a region within its country). | `subarea=Zlínský kraj` |
| <a id="param-subareacolor"></a>`subareacolor` | string | `#d03030` (varies by preset) | Fill and outline color of `subArea`. | `subareacolor=#c0392b` |
| <a id="param-subareaopacity"></a>`subareaopacity` | number, 0–1 | `0.35` (varies by preset) | Fill opacity of `subArea`. | `subareaopacity=0.35` |
| <a id="param-subareaoutlinewidth"></a>`subareaoutlinewidth` | number, 0–10 | `1.2` (varies by preset) | Outline width of `subArea` in px; 0 = none. | `subareaoutlinewidth=1.2` |
| <a id="param-worldview"></a>`worldview` | `ar` \| `bd` \| `br` \| `cn` \| `de` \| `eg` \| `es` \| `fr` \| `gb` \| `gr` \| `id` \| `il` \| `in` \| `it` \| `jp` \| `kr` \| `ma` \| `nl` \| `np` \| `pk` \| `pl` \| `ps` \| `pt` \| `ru` \| `sa` \| `se` \| `tr` \| `tw` \| `ua` \| `us` \| `vn` | — | Draw country borders as this country sees them (ISO 3166-1 alpha-2, e.g. `in`, `cn`, `us`, `ma`). Replaces the basemap's country and disputed borders with Natural Earth's borders for that worldview, and uses its country shapes for a highlighted country and for neighbor labels. Regions, cities and everything below country level stay OpenStreetMap. Default: the basemap's borders (OpenStreetMap, on-the-ground control). One of the 31 Natural Earth worldviews; the Locator maps guide explains what changes ("Disputed borders"). | `worldview=in` |

## Neighboring countries

Labels for the countries around the area. Requires `neighbors`; the other options refine it.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-neighbors"></a>`neighbors` | `name` \| `code` \| `flag` \| `flag+code` \| `flag+name` | `name` | What to show for each neighboring country: its name, its international vehicle registration code (D, A, SK…), its flag, or a flag with code/name. `false`/`none` turns them off. A literal `+` may arrive as a space; both work. | `neighbors=flag+code` |
| <a id="param-neighborfit"></a>`neighborfit` | `extend` \| `shrink` \| `drop` | `extend` | When a label does not fit in the visible part of its country: `extend` grows the image on that side (the output becomes larger than width×height; see `X-Image-Width`), `shrink` reduces the label to 70 %, `drop` omits it. | `neighborfit=extend` |
| <a id="param-neighborwhich"></a>`neighborwhich` | `touching` \| `visible` | `touching` | `touching` = countries bordering the area; `visible` = every other country in the frame. | `neighborwhich=visible` |
| <a id="param-neighborsize"></a>`neighborsize` | number, 6–32 | `12` | Text size in CSS px; flags are sized to match. | `neighborsize=12` |
| <a id="param-neighborcolor"></a>`neighborcolor` | string | — | Text color (default: the theme's muted label color). | `neighborcolor=#666666` |
| <a id="param-neighborupper"></a>`neighborupper` | boolean | `false` | Uppercase country names. | `neighborupper=true` |

## Labels and typography

Language and font of everything drawn on top of the basemap.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-lang"></a>`lang` | string | — | Label language (ISO 639-1). Default: local names (Deutschland, Polska), as on Wikipedia locator maps. | `lang=en` |
| <a id="param-font"></a>`font` | `noto-sans` \| `noto-serif` \| `noto-sans-mono` | `noto-sans` | A bundled family, or your own TTF/OTF/WOFF as a `data:` URI or an https URL on an allowed host (`WHEREBOX_FONT_HOSTS`). Missing glyphs fall back to Noto Sans, then Noto Sans Mono. Bundled families only in GET; custom fonts via POST. | `font=noto-serif` |
| <a id="param-fontweight"></a>`fontweight` | integer, 100–900 | `400` | Weight for all labels (100–900; the nearest bundled weight is used). | `fontweight=600` |

## Title band

An optional title band inside the requested width and height. Requires `title`; the other options refine it.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-title"></a>`title` | string | — | Title text (one line; long titles shrink, then get an ellipsis). | `title=Madrid – Seville` |
| <a id="param-titlepos"></a>`titlepos` | `top` \| `bottom` | `top` | Band above or below the map. | `titlepos=bottom` |
| <a id="param-titlealign"></a>`titlealign` | `left` \| `center` \| `right` | `left` | Text alignment in the band. | `titlealign=center` |
| <a id="param-titlesize"></a>`titlesize` | number, 8–64 | `18` | Text size in CSS px. | `titlesize=20` |
| <a id="param-titleweight"></a>`titleweight` | integer, 100–900 | `600` | Font weight. | `titleweight=700` |
| <a id="param-titlecolor"></a>`titlecolor` | string | — | Text color (default: the theme label color). | `titlecolor=#1a1a1a` |
| <a id="param-titlebg"></a>`titlebg` | string | — | Band background (default: white, or near-black on the dark preset). | `titlebg=#ffffff` |

## Legend

A numbered legend instead of labels on the map. Requires `legend`; the other options refine it.

| Parameter | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="param-legend"></a>`legend` | `right` \| `left` \| `top` \| `bottom` | `right` | Side of the map the legend panel goes on. `right`, `left`, `top` or `bottom` (`true` = right, `false`/`none` = off). | `legend=right` |
| <a id="param-legendtitle"></a>`legendtitle` | string | — | Heading above the legend entries. | `legendtitle=Stops` |
| <a id="param-legendsize"></a>`legendsize` | number, 8–32 | `13` | Legend text size in CSS px; the numbered circles scale with it. | `legendsize=13` |
| <a id="param-legendcolor"></a>`legendcolor` | string | — | Legend text color (default: the theme label color). | `legendcolor=#1a1a1a` |
| <a id="param-legendbg"></a>`legendbg` | string | — | Legend panel background (default: white, near-black on the dark preset, or the `background` of preset `none`). | `legendbg=#ffffff` |
| <a id="param-legendbadge"></a>`legendbadge` | string | — | Fill of the numbered circles (default: each point's marker color; route ends use the route color). | `legendbadge=#e02020` |

## POI options (inside `poi=`)

A `poi` value is a location followed by `|key:value` options: `lat,lon|label:Chřiby|marker:triangle`. The location is `lat,lon` or `place:Name`.

| Option | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="poi-label"></a>`label` | string | — | Label text. A newline (`\n` in GET) starts a new line. `\n` (backslash-n) starts a new line. `\|` cannot appear in a label in GET; use POST. | `label:Chřiby` |
| <a id="poi-pos"></a>`pos` | `auto` \| `right` \| `left` \| `top` \| `bottom` \| `top-right` \| `top-left` \| `bottom-right` \| `bottom-left` | `auto` | Where the label goes relative to the marker. `auto` picks the first free spot and falls back to a leader line. | `pos:bottom` |
| <a id="poi-labelsize"></a>`labelsize` | number, 6–48 | `16` | Label text size in CSS px. | `labelsize:16` |
| <a id="poi-weight"></a>`weight` | integer, 100–900 | — | Font weight for this label (overrides `font.weight`). | `weight:700` |
| <a id="poi-labelcolor"></a>`labelcolor` | string | — | Label color (default: the basemap theme's label color). | `labelcolor:#1a1a1a` |
| <a id="poi-leader"></a>`leader` | boolean | `true` | When no free spot is next to the marker, place the label further out with a thin leader line. | `leader:false` |
| <a id="poi-marker"></a>`marker` | `pin` \| `dot` \| `ring` \| `flag` \| `triangle` \| `circle` \| `square` \| `star` \| `diamond` | — | Marker preset. Defaults depend on the role: plain point → `pin`, route start → `ring`, route finish → `flag`. | `marker:triangle` |
| <a id="poi-color"></a>`color` | string | — | Marker fill color. | `color:#e02020` |
| <a id="poi-size"></a>`size` | number, 4–64 | — | Marker height in CSS pixels (multiplied by `scale`). Default depends on the shape. | `size:14` |
| <a id="poi-stroke"></a>`stroke` | string | — | Outline color (default white where the shape has an outline). | `stroke:#ffffff` |
| <a id="poi-strokewidth"></a>`strokewidth` | number, 0–8 | — | Outline width in px; 0 = none. `dot` and `pin` have a thin default outline. | `strokewidth:1.5` |
| <a id="poi-icon"></a>`icon` | string | — | Custom icon instead of the shape: an SVG/PNG `data:` URI, or an https URL on a host the server allows (`WHEREBOX_ICON_HOSTS`). SVGs with external references or scripts are rejected. URL-encode the value (base64 contains `+`, `/` and `=`). | `icon:data:image/svg+xml;base64,PHN2Zy8+` |
| <a id="poi-anchor"></a>`anchor` | `center` \| `bottom` | — | Which point of a custom icon sits on the location: its center, or its bottom edge (pin-shaped icons). | `anchor:bottom` |

## Shape options (inside `shape=`)

A `shape` value is optional `key:value|` style options followed by the geometry, which is always the last part (everything after its prefix is taken as is, so polylines and GeoJSON need no escaping beyond URL-encoding): `color:#d01c1c|width:3|line:50.08,14.42;49.19,16.61`.

| Option | Value | Default | Description | Example |
|---|---|---|---|---|
| <a id="shape-color"></a>`color` | string | `#555555` | Line color of the shape. | `color:#d01c1c` |
| <a id="shape-width"></a>`width` | number, 0–20 | `2` | Line width in px; 0 = no line. | `width:3` |
| <a id="shape-dash"></a>`dash` | array | — | Dash pattern in line widths. Comma-separated. | `dash:3,2` |
| <a id="shape-opacity"></a>`opacity` | number, 0–1 | `1` | Line opacity. | `opacity:0.9` |
| <a id="shape-fill"></a>`fill` | string | — | Fill color for polygons (no fill if unset). | `fill:#ffcc00` |
| <a id="shape-fillopacity"></a>`fillopacity` | number, 0–1 | `0.25` | Fill opacity for polygons. | `fillopacity:0.3` |

| Geometry | Value | Example |
|---|---|---|
| <a id="shape-line"></a>`line:` | `lat,lon;lat,lon;…` (at least 2 points). | `line:50.08,14.42;49.19,16.61` |
| <a id="shape-polygon"></a>`polygon:` | `lat,lon;…` (at least 3 points; closed automatically). | `polygon:50.1,14.3;50.1,14.6;49.9,14.6;49.9,14.3` |
| <a id="shape-polyline"></a>`polyline:` | Encoded polyline, precision 5 (Google). URL-encode it. | ``polyline:_p~iF~ps\|U_ulLnnqC_mqNvxq`@`` |
| <a id="shape-polyline6"></a>`polyline6:` | Encoded polyline, precision 6 (Valhalla/OSRM). | `polyline6:…` |
| <a id="shape-geojson"></a>`geojson:` | Any GeoJSON geometry, Feature or FeatureCollection (URL-encode it). | `geojson:{"type":"LineString","coordinates":[[14.42,50.08],[16.61,49.19]]}` |

## POST-only

These MapSpec fields cannot be set from a query string; send them in the JSON body of `POST /v1/map`.

- `routes.1+`
- `font.family (custom fonts)`
- `area (GeoJSON)`
- `pois.*.marker.icon (long data URIs work but POST is recommended)`

## Unknown parameters and cache busters

An unknown parameter is rejected with `400` ([`invalid-spec`](/docs/errors.md#invalid-spec)) and, when one is close, a "did you mean" hint. Parameters starting with `_` (for example `_v=3`) are ignored by the parser, so they can be used to bust caches.