> ## Documentation Index
> Fetch the complete documentation index at: https://docs.myme.so/llms.txt
> Use this file to discover all available pages before exploring further.

# List edge types

> Returns every edge type registered in the tenant — the eight core types (`about`, `parent-of`, `in-thread`, `attached-to`, `references`, `authored-by`, `derived-from`, `supersedes`) plus any custom types registered via `POST /edges/types`. Each entry carries its cardinality, cascade behaviour, and source/target type constraints.



## OpenAPI

````yaml /openapi.json get /edges/types
openapi: 3.1.0
info:
  title: Marfa API
  version: 4.2.0
  description: Typed data layer for structured personal data
servers: []
security: []
paths:
  /edges/types:
    get:
      tags:
        - EdgeTypes
      summary: List edge types
      description: >-
        Returns every edge type registered in the tenant — the eight core types
        (`about`, `parent-of`, `in-thread`, `attached-to`, `references`,
        `authored-by`, `derived-from`, `supersedes`) plus any custom types
        registered via `POST /edges/types`. Each entry carries its cardinality,
        cascade behaviour, and source/target type constraints.
      responses:
        '200':
          description: Edge types
          content:
            application/json:
              schema:
                type: object
                properties:
                  edge_types:
                    type: array
                    items:
                      type: object
                      properties:
                        id:
                          type: string
                        label:
                          type: string
                        description:
                          type: string
                        cardinality:
                          type: string
                          enum:
                            - one-to-one
                            - one-to-many
                            - many-to-one
                            - many-to-many
                        source_type_constraints:
                          type: array
                          items:
                            type: string
                        target_type_constraints:
                          type: array
                          items:
                            type: string
                        cascade_on_delete:
                          type: string
                          enum:
                            - cascade
                            - orphan
                            - block
                        property_schema:
                          type: object
                          additionalProperties:
                            nullable: true
                      required:
                        - id
                        - cardinality
                        - source_type_constraints
                        - target_type_constraints
                        - cascade_on_delete
                        - property_schema
                required:
                  - edge_types
      security:
        - bearerAuth: []
components:
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer
      bearerFormat: API Key or OAuth Token
      description: Pass an API key (marfa_k1_...) or OAuth access token (marfa_at_...)

````