---
title: "Meta knowledge graph representation of this TRAPI web service."
method: GET
path: "/meta_knowledge_graph"
tags: ["meta_knowledge_graph"]
---

# Meta knowledge graph representation of this TRAPI web service.

`GET /meta_knowledge_graph`

## Query parameters

- `format` string

## Response `200`

Returns meta knowledge graph representation of this TRAPI web service.

- MetaKnowledgeGraph — Knowledge-map representation of this TRAPI web service. The meta knowledge graph is composed of the union of most specific categories and predicates for each node and edge.
  - `nodes` object, required — Collection of the most specific node categories provided by this TRAPI web service, indexed by Biolink class CURIEs. A node category is only exposed here if there is node for which that is the most specific category available.
  - `edges` MetaEdge[], required — List of the most specific edges/predicates provided by this TRAPI web service. A predicate is only exposed here if there is an edge for which the predicate is the most specific available.
    - `subject` string, required — Compact URI (CURIE) for a Biolink class, biolink:NamedThing or a child thereof. The CURIE must use the prefix 'biolink:' followed by the PascalCase class name.
    - `predicate` string, required — CURIE for a Biolink 'predicate' slot, taken from the Biolink slot ('is_a') hierarchy rooted in biolink:related_to (snake_case). This predicate defines the Biolink relationship between the subject and object nodes of a biolink:Association defining a knowledge graph edge.
    - `object` string, required — Compact URI (CURIE) for a Biolink class, biolink:NamedThing or a child thereof. The CURIE must use the prefix 'biolink:' followed by the PascalCase class name.
    - `knowledge_types` string[], nullable — A list of knowledge_types that are supported by the service. If the knowledge_types is null, this means that only 'lookup' is supported. Currently allowed values are 'lookup' or 'inferred'.
    - `attributes` MetaAttribute[], nullable — Edge attributes provided by this TRAPI web service.
      - `attribute_type_id` string, required — A Compact URI, consisting of a prefix and a reference separated by a colon, such as UniProtKB:P00738. Via an external context definition, the CURIE prefix and colon may be replaced by a URI prefix, such as http://identifiers.org/uniprot/, to form a full URI.
      - `attribute_source` string, nullable — Source of an attribute provided by this TRAPI web service.
      - `original_attribute_names` string[], nullable — Names of an the attribute as provided by the source.
      - `constraint_use` boolean — Indicates whether this attribute can be used as a query constraint.
      - `constraint_name` string, nullable — Human-readable name or label for the constraint concept. Required whenever constraint_use is true.
    - `qualifiers` MetaQualifier[], nullable — Qualifiers that are possible to be found on this edge type.
      - `qualifier_type_id` string, required — A Compact URI, consisting of a prefix and a reference separated by a colon, such as UniProtKB:P00738. Via an external context definition, the CURIE prefix and colon may be replaced by a URI prefix, such as http://identifiers.org/uniprot/, to form a full URI.
      - `applicable_values` string[] — The list of values that are possible for this qualifier.
    - `association` string — Compact URI (CURIE) for a Biolink class, biolink:NamedThing or a child thereof. The CURIE must use the prefix 'biolink:' followed by the PascalCase class name.

---

[API](https://skmtc.net/rtxteam/apis/rtx-kg2-trapi-1-5-0.md) · [All operations](https://skmtc.net/rtxteam/apis/rtx-kg2-trapi-1-5-0/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/rtxteam/rtx-kg2-trapi-1-5-0/versions/e65b311ece6d/schema)