discriminator

Category: Keyword — presence of a specific JSON Schema keyword triggers this rule

Error Codes

Profile	Code	Severity
openai.so.2026-04-30	OAI-K-discriminator	Warn
anthropic.so.2026-04-30	ANT-K-discriminator	Forbid

Description

Flag usage of the 'discriminator' keyword according to the active provider profile.

Provider Evidence

Profile	Status	Source	Basis
anthropic.so.2026-04-30	unknown	—	Anthropic does not document this OpenAPI keyword for Structured Outputs.
openai.so.2026-04-30	inferred	OpenAI supported schemas	OpenAPI-only keyword absent from OpenAI's supported JSON Schema subset.

Rationale

Provider profiles may enforce different behavior and severity for this rule; use the table below for the selected profile.

Bad Example

{ "type": "object", "discriminator": true, "properties": {} }

Good Example

{
  "type": "object",
  "properties": {
    "name": { "type": "string" }
  }
}