Which JSON Schema keywords a Sume Format output_schema accepts

Sume Format schemas use an allowlist: unknown keywords fail with unsupported_keyword. Number bounds are allowed; oneOf and allOf are not. Table inside.

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A Sume Format output_schema is checked against an allowlist, not a blacklist. A keyword that is not on the list is a violation and returns unsupported_keyword. Number bounds minimum, maximum, exclusiveMinimum, exclusiveMaximum and multipleOf are on it. oneOf and allOf are not, so use anyOf. The root must be an object, every node needs a type, and $ref: "#" root recursion is refused even though OpenAI strict mode permits it. Source: Formats structured output, read 2026-10-06.

What passes and what fails?

A short map of the cases the docs call out.

Schema keyword allowlist, read 2026-10-06 from docs.sume.com.
Keyword or shapeStatusDo this instead
minimum, maximum, multipleOfAllowed on numbersKeep them
exclusiveMinimum, exclusiveMaximumAllowed on numbersKeep them
oneOf, allOfRejectedanyOf
Node with no typeRejectedAdd a type
Non-object rootRejectedWrap in an object
$ref: "#" at the rootRejectedInline the shape

Where do I see the exact list?

The structured-output page lists every allowed keyword per type. Copy from it, and run your schema in a test Format run before you wire it into production code.

Sources

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