not

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

Error Codes

Profile	Code
openai.so.2026-04-30	OAI-K-not
anthropic.so.2026-04-30	ANT-K-not

Description

Flag usage of the 'not' keyword, which is not supported by openai.so.2026-04-30

Rationale

The openai.so.2026-04-30 structured-output provider rejects the 'not' keyword. Schemas using this keyword may be rejected or silently altered.

Bad Example

{ "type": "object", "not": true, "properties": {} }

Good Example

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