2025-03-27 2026-02-02 Specification Required Ari Keranen (primary), Michael Koster (backup) $comment source code comments only, no semantics IETF const constant value IETF contentFormat content format IETF default default value IETF description long description text IETF enum sdfChoice limited to text strings IETF exclusiveMaximum exclusive maximum for a number IETF exclusiveMinimum exclusive minimum for a number IETF format specific format for a text string IETF items items of an array IETF label short text (no constraints); defaults to key IETF maxItems maximum number of items in an array IETF maxLength maximum length for a text string (in characters, i.e., Unicode scalar values) IETF maximum maximum for a number IETF minItems minimum number of items in an array IETF minLength minimum length for a text string (in characters, i.e., Unicode scalar values) IETF minimum minimum for a number IETF multipleOf step size of number IETF nullable boolean: can the item be left out? IETF observable boolean: can the item be observed? IETF pattern regular expression pattern for a text string IETF properties named dataqualities for type="object" IETF readable boolean: can the item be read? IETF required which data items are required? IETF sdfChoice named dataqualities for a choice IETF sdfData named dataqualities for an independent data type definition IETF sdfInputData input data to an action IETF sdfOutputData output data of an action or event (sdfRequired applies here) IETF sdfRef sdf-pointer to definition being referenced IETF sdfRequired pointer-list to declarations of required components IETF sdfRequiredInputData pointer-list to declarations of required input data for an action IETF sdfType more detailed information about the type of a string IETF type general category of data type IETF uniqueItems boolean: do the items of the array need to be all different? IETF unit engineering unit and scale (per SenML registry) IETF writable boolean: can the item be written to? IETF Expert Review Ari Keranen (primary), Michael Koster (backup) Specification Required Ari Keranen (primary), Michael Koster (backup) byte-string A sequence of zero or more bytes string base64url without padding RFC 8949, Section 3.4.5.2 IETF unix-time A point in civil time number POSIX time RFC 8949, Section 3.4.2 IETF Note that the definition of unix-time does not imply the capability to represent points in time that fall on leap seconds. More date/time-related sdfTypes are likely to be added in the sdfType value registry. Specification Required Ari Keranen (primary), Michael Koster (backup)