The ontology is a declarative YAML file that defines the structure of your knowledge graph. It specifies the types of entities and relationships that can exist in your graph, acting as a schema to ensure data consistency and to guide the query generation process. By defining a clear and explicit ontology, you enable a1facts to validate incoming data and construct precise queries.

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Example

Here is an example of an ontology for financial analysis, taken from the Stock Analysis cookbook example.
company.yaml
name: company_info
description: "Ontology for company information"
entities:
  - name: Company
    description: "A company"
    properties:
      - name: name
        type: string
        description: "The name of the company"
      - name: ticker
        type: string
        description: "The stock ticker of the company"
      - name: description
        type: string
        description: "A description of the company"
  - name: Product_Service
    description: "A product or service offered by a company"
    properties:
      - name: name
        type: string
        description: "The name of the product or service"
  - name: Market
    description: "A market that a company operates in"
    properties:
      - name: name
        type: string
        description: "The name of the market"
relationships:
  - name: competes_with
    description: "A company competes with another company"
    domain: Company
    range: Company
  - name: offers
    description: "A company offers a product or service"
    domain: Company
    range: Product_Service
  - name: operates_in
    description: "A company operates in a market"
    domain: Company
    range: Market

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Key Concepts

The ontology is defined by the following key concepts, which are organized into a hierarchical structure in the YAML file.