The example below shows a subset of the record for Chemical Entities of Biological Interest (ChEBI) that highlights three parts:

  1. uri_format - this is the default string used to turn a local unique identifier into a URL for resolution. Many Bioregistry records reuse the uri_format annotation from an external registry like, so you might notice in the edit file that this is missing. Even when a uri_format is available from external registries, it can still be explicitly overriden. URI format strings use a $1 as the placeholder for the local unique identifier.
  2. rdf_uri_format - the semantic web community prefers to have exactly one URI format string that is used in all semantic web artifacts. When this is not controversial, it can be explicitly annotated, such as for OBO Foundry ontologies.
  3. providers - this is a place to put additional URI format strings, that are either useful for resolution or for parsing non-resolvable URIs that may appear in data. Each provider requires a minimum of 5 pieces of information:
    1. code - A short code that represents this provider. It is not globally unique, but it must be locally unique with respect to other providers in a given Bioregistry record
    2. homepage, description, name - helpful metadata for users and curators to understand why this provider exists and what it does
    3. uri_format - the URI format, same as above
  "chebi": {
    "name": "Chemical Entities of Biological Interest",
    "uri_format": "$1",
    "rdf_uri_format": "$1",
    "providers": [
        "code": "chebi-img",
        "description": "Image server from chebi",
        "homepage": "",
        "name": "ChEBI",
        "uri_format": "$1"

What Should I Curate as a Provider?

  1. Additional endpoints that give different kinds of information, such as image resolution, JSON/XML/structured data artifacts, or other
  2. URI patterns that appear in data, but aren’t necessarily for resolution

What Can I Do with Providers?

The Bioregistry resolver has the ability to redirect based on providers. For example, will redirect based on the default URI format string associated with the chebi prefix, but the provider parameter can be provided to redirect using a different provider based on its code. This means that will redirect to a 2D depiction of the chemical structure of alsterpaullone.