Label Tags API #

The Label Tags API provides a comprehensive list of tags that can be applied to labels in Project Sidewalk. Each label type has its own set of tags, which can be used to provide additional information about the sidewalk barrier or feature.

Each city can also be customized with its own set of label tags, reflecting the unique needs and characteristics of the area.

Label Tags API Preview #

Below is a live preview of the label tags available in San Pedro Garza García, Mexico grouped by label type, retrieved directly from the API:

Loading label tags data...

Endpoint #

Retrieve a list of all label tags with their metadata.

GET /v3/api/labelTags

Examples#

/v3/api/labelTags Get all label tags available for San Pedro Garza García, Mexico (in JSON)

Quick Download #

Download label tags data directly in JSON:

Preparing your download...

This should only take a few seconds.

Responses#

Success Response (200 OK)#

On success, the API returns an HTTP 200 OK status code and a JSON object containing an array of label tags.

{
  "status": "OK",
  "label_tags": [
    {
      "id": 1,
      "label_type": "CurbRamp",
      "tag": "narrow",
      "description": "The ramp is not wide enough for a wheelchair to safely use it",
      "mutually_exclusive_with": []
    },
    {
      "id": 3,
      "label_type": "CurbRamp",
      "tag": "missing tactile warning",
      "description": "The ramp is missing a tactile warning strip, which is a textured surface that alerts people with visual impairments to existence of the ramp and crossing",
      "mutually_exclusive_with": [
        "tactile warning"
      ]
    },
    // ... more label tags
  ]
}

Response Fields #

Field	Type	Description
`status`	`string`	Always "OK" for successful responses.
`label_tags`	`array`	Array of label tag objects.
`label_tags[].id`	`integer`	Unique identifier for the tag.
`label_tags[].label_type`	`string`	The label type this tag applies to (e.g., "CurbRamp", "Obstacle").
`label_tags[].tag`	`string`	Name of the tag (e.g., "narrow", "missing tactile warning").
`label_tags[].description`	`string`	Human-readable description of the tag.
`label_tags[].mutually_exclusive_with`	`array[string]`	Array of tag names that cannot be applied simultaneously with this tag.

Error Responses#

If an error occurs, the API will return an appropriate HTTP status code and a JSON response body containing details about the error.

500 Internal Server Error: An unexpected error occurred on the server.
503 Service Unavailable: The server is temporarily unable to handle the request (e.g., during maintenance).

Error Response Body #

All errors are returned as RFC 7807 “problem details” with the application/problem+json content type and the following structure:

{
  "type": "about:blank",          // RFC 7807 problem-type URI ("about:blank" means no type beyond the status)
  "title": "Invalid Parameter",   // Short, human-readable summary of the problem type (stable for a given code)
  "status": 400,                  // HTTP status code (also repeated in the body)
  "detail": "Invalid value for the bbox parameter. Expected format: minLng,minLat,maxLng,maxLat.", // This occurrence
  "code": "INVALID_PARAMETER",    // Stable, machine-readable error code you can branch on
  "parameter": "bbox"             // Extension member: the specific parameter at fault (omitted when not applicable)
}

Terms of Use #

If you use Project Sidewalk data in your research, please cite the following paper (awarded 🏆 Best Paper at CHI 2019):

Manaswi Saha, Michael Saugstad, Hanuma Teja Maddali, Aileen Zeng, Ryan Holland, Steven Bower, Aditya Dash, Sage Chen, Anthony Li, Kotaro Hara, and Jon Froehlich. 2019. Project Sidewalk: A Web-based Crowdsourcing Tool for Collecting Sidewalk Accessibility Data At Scale. In Proceedings of the 2019 CHI Conference on Human Factors in Computing Systems (CHI '19). Association for Computing Machinery, New York, NY, USA, Paper 62, 1–14.

Contribute#

Project Sidewalk is an open-source project created by the Makeability Lab and hosted on GitHub. We welcome your contributions! If you found a bug or have a feature request, please open an issue on GitHub.

You can also email us at sidewalk@cs.uw.edu

Project Sidewalk in Your City!#

If you are interested in bringing Project Sidewalk to your city, please read our Wiki page.