--- title: "Download a package's classes as an ontology file a collection takes as its own" method: GET path: "/api/v0/graph-packages/{slug}/{version}/ontology" tags: ["Knowledge Base Graph"] --- # Download a package's classes as an ontology file a collection takes as its own `GET /api/v0/graph-packages/{slug}/{version}/ontology` ## Request - Base URL: `https://api.outerport.com` (the document declares no server; this is the origin it was published from) - URL: `https://api.outerport.com/api/v0/graph-packages/{slug}/{version}/ontology` - Auth: HTTP bearer - TypeScript: (a function with typed inputs; its response is checked against the schema) The package's classes and relationships, in the caller's language, as the entity_types and relationship_types POST /{kb_id}/graph/ontology takes, with no packages key: applied to a collection, they become its own classes, which it edits freely. Applied to a collection that subscribes to the same package, each class is that collection's edited version of the package's instead. ## Path parameters - `slug` string, required - `version` string, required ## Response `200` Successful Response - OntologyDocumentOutput: The ontology file. Unknown keys are refused so a misspelt section is an error, not a no-op. - `format` 'outerport.kg-ontology' - `format_version` 1 - `collection_name` string - `packages` OntologyPackageOutput[], nullable - `slug` string, required - `version` string, required - `display_name` string - `entity_types` OntologyPackageEntityTypeOutput[] - `type_id` string, required - `display_name` string, required - `description` string, required - `tier` 'representation' | 'domain', required - `attribute_fields` AttributeFieldSpec[] - `name` string, required - `kind` string, required - `required` boolean - `description` string - `enum_values` string[], nullable - `label` string, nullable - `instant` boolean: Whether the field holds an ISO-8601 date or time a reader may order records by: always for a date or datetime field, and for a text field its type declares holds one. - `derived_properties` DerivedPropertyDefOutput[] - `id` string, required - `description` string - `rule` union, required - PatternMapRule: Derive a value from one stored field on the same entity: the field's text is matched (case-insensitive ``re.search``) against ``cases`` in order; misses fall back to ``default``. ``source_field`` is ``"name"`` or a stored-attribute id, never another derived property. - `kind` 'pattern_map' - `source_field` string - `cases` PatternCase[], required - … - `default` string, nullable - EdgeDegreeRule: Derive the count of the entity's own incident edges of one relationship type. ``node_role`` picks which end the entity sits on (``source`` = outgoing, ``target`` = incoming, ``either`` = both). - `kind` 'edge_degree' - `relationship_type_id` string, required - `node_role` 'source' | 'target' | 'either' - `minimum` integer: How many of these edges the ontology requires an instance to have. Zero means optional: an instance with none is complete, and no reader may present it as missing anything. This is the cardinality constraint — a count on its own is a measurement, and deciding after the fact that a zero looks wrong because other instances have more is a guess about the corpus rather than a statement of the ontology. - `label` string, nullable - `relationship_types` OntologyPackageRelationshipType[] - `type_id` string, required - `display_name` string, required - `description` string, required - `source_tier` 'representation' | 'domain', required - `target_tier` 'representation' | 'domain', required - `source_entity_type_ids` string[] - `target_entity_type_ids` string[] - `attribute_fields` AttributeFieldSpec[] - `name` string, required - `kind` string, required - `required` boolean - `description` string - `enum_values` string[], nullable - `label` string, nullable - `instant` boolean: Whether the field holds an ISO-8601 date or time a reader may order records by: always for a date or datetime field, and for a text field its type declares holds one. - `symmetric` boolean - `entity_types` EntityTypeUpsertRequestOutput[] - `type_id` string, required - `display_name` string, required - `description` string - `tier` 'representation' | 'domain', required - `attribute_fields` AttributeFieldSpec[] - `name` string, required - `kind` string, required - `required` boolean - `description` string - `enum_values` string[], nullable - `label` string, nullable - `instant` boolean: Whether the field holds an ISO-8601 date or time a reader may order records by: always for a date or datetime field, and for a text field its type declares holds one. - `derived_properties` DerivedPropertyDefOutput[] - `id` string, required - `description` string - `rule` union, required - PatternMapRule: Derive a value from one stored field on the same entity: the field's text is matched (case-insensitive ``re.search``) against ``cases`` in order; misses fall back to ``default``. ``source_field`` is ``"name"`` or a stored-attribute id, never another derived property. - `kind` 'pattern_map' - `source_field` string - `cases` PatternCase[], required - `pattern` string, required - `value` string, required - `default` string, nullable - EdgeDegreeRule: Derive the count of the entity's own incident edges of one relationship type. ``node_role`` picks which end the entity sits on (``source`` = outgoing, ``target`` = incoming, ``either`` = both). - `kind` 'edge_degree' - `relationship_type_id` string, required - `node_role` 'source' | 'target' | 'either' - `minimum` integer: How many of these edges the ontology requires an instance to have. Zero means optional: an instance with none is complete, and no reader may present it as missing anything. This is the cardinality constraint — a count on its own is a measurement, and deciding after the fact that a zero looks wrong because other instances have more is a guess about the corpus rather than a statement of the ontology. - `label` string, nullable - `source_bindings` SourceBindingSpec[] - `source_kind` string, required: A source in the source schema catalog, e.g. email. - `role` string, required: A class role or link role that source offers. - `field_map` object: Attribute of the class -> field of the role that fills it. A relationship's binding maps nothing. - `relationship_types` RelationshipTypeUpsertRequest[] - `type_id` string, required - `display_name` string, required - `description` string - `source_tier` 'representation' | 'domain', required - `target_tier` 'representation' | 'domain', required - `attribute_fields` AttributeFieldSpec[] - `name` string, required - `kind` string, required - `required` boolean - `description` string - `enum_values` string[], nullable - `label` string, nullable - `instant` boolean: Whether the field holds an ISO-8601 date or time a reader may order records by: always for a date or datetime field, and for a text field its type declares holds one. - `source_bindings` SourceBindingSpec[] - `source_kind` string, required: A source in the source schema catalog, e.g. email. - `role` string, required: A class role or link role that source offers. - `field_map` object: Attribute of the class -> field of the role that fills it. A relationship's binding maps nothing. - `symmetric` boolean: The relationship has no direction, such as two items joined by a pipe. An edited package relationship keeps the package's setting. ## Other responses - `422`: Validation Error ## Changes - **2026-11-09** `ecd5b922e78a`: 1 info - endpoint added [Operation history](https://skmtc.dev/outerport/apis/outerport-api/changes/api/v0/graph-packages/:slug/:version/ontology/get.md) --- [API](https://skmtc.dev/outerport/apis/outerport-api.md) - [All operations](https://skmtc.dev/outerport/apis/outerport-api/llms.txt) - [OpenAPI document](https://skmtc.dev/outerport/apis/outerport-api/revisions/08b5bf6f7f18?raw)