anyof-objects

Category: Semantic — schema semantics trigger this rule

Error Codes

Profile	Code	Severity
openai.so.2026-04-30	OAI-S-anyof-objects	Warn
anthropic.so.2026-04-30	ANT-S-anyof-objects	Warn

Description

anyOf with only object-typed branches may not be fully supported

Provider Evidence

Profile	Status	Source	Basis
anthropic.so.2026-04-30	inferred	Anthropic JSON Schema limitations	Each anyOf branch must remain within Anthropic's supported subset.
openai.so.2026-04-30	documented	OpenAI anyOf requirements	—

Rationale

When all anyOf branches are object-typed, some providers may not correctly resolve the union. Merging branches into a single object schema when appropriate improves compatibility across providers.

Bad Example

{
  "type": "object",
  "anyOf": [
    { "type": "object", "properties": { "x": { "type": "string" } } },
    { "type": "object", "properties": { "y": { "type": "number" } } }
  ]
}

Good Example

{
  "type": "object",
  "properties": {
    "x": { "type": "string" },
    "y": { "type": "number" }
  }
}