Features

Features are entities detected inside Blocks — rooms, doors, symbols, walls, dimensions, and annotations. They form a containment tree via parent_feature_id and connect to other entities via Relations. See Features for the full concept.

Endpoints

Method	Endpoint	Description
`GET`	`/features`	List features
`GET`	`/features/{id}`	Get feature details

Features are read-only. They are created automatically during block processing.

Feature Object

Field	Type	Description
`id`	string	Unique identifier (e.g., `ftr_01JABCD123`)
`block_id`	string	Parent Block
`parent_feature_id`	string?	Containment parent feature (null = direct child of block)
`type`	string	Entity type: `"room"`, `"door"`, `"wall"`, `"duplex_receptacle"`
`label`	string?	Instance identifier: `"201"`, `"104"`, `"AHU-1"`
`bounds`	object?	Geometry within the block (see below)
`confidence`	float?	Detection confidence score (0-1)
`uri`	string?	Cropped image URL
`ocr`	string?	Extracted text content
`description`	string?	Human/LLM-readable summary
`metadata`	object?	Domain-specific properties
`created_at`	datetime	Creation timestamp
`updated_at`	datetime	Last update timestamp

Bounds Geometry

The bounds field stores the feature’s geometry within its parent block. A type discriminator determines the shape:

Geometry	Used for	Shape
`bbox`	Symbols, equipment, doors	Axis-aligned bounding box
`polygon`	Rooms, areas	Closed polygon with vertices
`polyline`	Walls, ducts, pipes	Open line with vertices

// bbox — a door symbol
{ "type": "bbox", "xmin": 450, "ymin": 320, "xmax": 480, "ymax": 350 }

// polygon — a room boundary
{ "type": "polygon", "points": [[100, 200], [300, 200], [300, 500], [100, 500]] }

// polyline — a wall segment
{ "type": "polyline", "points": [[100, 200], [300, 200], [300, 500]] }

All coordinates are normalized (0-1000) within the parent block’s image. This makes them resolution-independent.

Feature Metadata

The metadata JSON field carries domain-specific properties, standardized by convention:

Key	Used on	Example
`fire_rating`	Walls, doors	`2-hr`, `45-min`
`elevation`	Beams, ducts, equipment	`112'-6`
`elevation_top`	Beams, structural members	`112'-6`
`elevation_bottom`	Beams, structural members	`111'-2`
`material`	Walls, doors	`HM`, `WD`, `concrete`
`size`	Ducts, pipes	`24x12`, `4`
`assembly`	Walls	`UL U419`
`system`	MEP elements	`CHW`, `SAN`, `SD`
`designation`	Structural members	`W16x40`

Symbol Instance Metadata

Detected symbol instances (from the symbol detection pipeline) carry matching metadata:

Key	Type	Description
`scale`	float	Template scale factor relative to legend crop (0.4 - 1.3)
`angle`	int	Rotation angle in degrees: 0, 45, 90, 135, 180, 225, 270, 315
`flipped`	bool	Whether the instance is vertically flipped relative to the legend
`template_confidence`	float	Raw template matching score before embedding verification
`dinov2_score`	float	Embedding similarity score from DINOv2 verification

The confidence field on symbol features is a hybrid score: template_confidence * dinov2_score. Both component scores are preserved in metadata for downstream filtering.

{
  "type": "symbol",
  "label": "duplex_receptacle",
  "confidence": 0.82,
  "bounds": { "type": "bbox", "xmin": 450, "ymin": 320, "xmax": 480, "ymax": 350 },
  "metadata": {
    "scale": 0.88,
    "angle": 90,
    "flipped": false,
    "template_confidence": 0.91,
    "dinov2_score": 0.90
  }
}

Legend Feature Metadata

Legend entry features (from parse_legend) carry symbol definition metadata:

Key	Type	Description
`is_text_only`	bool	True if the symbol is text-only with no graphic shape
`has_text`	bool	True if the symbol graphic contains text characters
`symmetrical`	bool	True if the graphic is symmetric along either axis
`is_suffix`	bool	True if this entry is a suffix designation (e.g., “WP” for weatherproof)
`suffix`	string?	The suffix letter(s) when `is_suffix` is true

Text-only legend entries are not template-matched against plan blocks.

Type Vocabulary

type is a free string — the vocabulary of construction entities is too large for an enum. Common types include:

Category	Types
Architectural	`room`, `door`, `wall`, `window`, `column`, `stair`
Electrical	`duplex_receptacle`, `gfci_receptacle`, `switch`, `light_fixture`, `fire_alarm_pull_station`
Mechanical	`duct`, `diffuser`, `ahu`, `vav_box`
Plumbing	`pipe`, `fixture`, `floor_drain`
Structural	`beam`, `joist`, `footing`
Annotations	`dimension`, `detail_callout`, `keynote`, `section_mark`
Fire protection	`smoke_detector`, `sprinkler_head`, `fire_extinguisher`

Getting Started

CMS API

Vision API

Errors

Endpoints

Feature Object

Bounds Geometry

Feature Metadata

Symbol Instance Metadata

Legend Feature Metadata

Type Vocabulary

​Endpoints

​Feature Object

​Bounds Geometry

​Feature Metadata

​Symbol Instance Metadata

​Legend Feature Metadata

​Type Vocabulary

Endpoints

Feature Object

Bounds Geometry

Feature Metadata

Symbol Instance Metadata

Legend Feature Metadata

Type Vocabulary