Element Category Matrix

The following matrix provides a quick reference for the structural differences and capabilities of the various categories of elements within the Information System.

| Category | Topological Role | Independent Identity | Primary API Path | Context Membership | Custom Fields Allowed (Schema-Mixed) | |—|—|:—:|:—:|:—:|:—:| | Context | Logical Partition | ✅ Yes (UUID) | /contexts | ❌ N/A (Defines the boundary) | ❌ No | | Type | Type Schema | ✅ Yes (UUID & Name) * | /types | ❌ N/A (Global definition) | ❌ No | | Resource | Graph Node (Hub) | ✅ Yes (UUID) | /instances | ✅ Yes | ❌ No (Topological extensibility only) | | Facet | Graph Node (Satellite) | ✅ Yes (UUID) | /instances | ✅ Yes | ✅ Yes | | IsRelatedTo | Graph Edge (Association) | ✅ Yes (UUID) | /instances | ✅ Yes | ✅ Yes | | ConsistsOf | Graph Edge (Composition) | ✅ Yes (UUID) | /instances | ✅ Yes | ✅ Yes | | Property | Nested Data Value | ❌ No | ❌ N/A (Embedded) | ❌ N/A (Embedded) | ✅ Yes | | QueryTemplate | Stored Query Definition | ✅ Yes (UUID & Name) * | /query-templates | ❌ N/A (Global definition) | ❌ No |

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* UUID & Name Identity: These elements physically possess a globally unique UUID — either supplied by the client at creation (honored if not already in use by another entity) or, if omitted, generated by the system. However, to maximize human-readability and ease of use, the REST API endpoints are designed to address them exclusively using their unique name field (e.g., /types/{name} or /query-templates/{name}). Clients never need to know, retrieve, or use the underlying internal UUIDs for these System Objects.