jsonld-ex Vocabulary Specification

Status: Draft Specification v0.1.0
Date: 2026-02-12
Part of: JSON-LD Extensions for AI/ML (jsonld-ex)

1. Introduction

This document defines the complete vocabulary of the jsonld-ex extension. Every class and property listed here is implemented in the reference implementation and tested against 832+ unit and integration tests.

Terms are organized into functional categories. For each term, the specification provides:

IRI — the full Internationalized Resource Identifier
Compact form — the @-prefixed keyword used in JSON-LD documents
Type — the expected XSD datatype or structural type
Domain — what kind of JSON-LD construct the term applies to
Range — the set of allowed values
Description — normative prose defining the term’s semantics
Processing rules — requirements on conforming processors (using RFC 2119 keywords)
Example — a minimal JSON-LD snippet

1.1 Namespace

All terms in this vocabulary are defined under the namespace:

https://w3id.org/jsonld-ex/

The preferred prefix is jex:. For example, the full IRI of the confidence property is https://w3id.org/jsonld-ex/confidence.

1.2 Conformance

The key words “MUST”, “MUST NOT”, “REQUIRED”, “SHALL”, “SHALL NOT”, “SHOULD”, “SHOULD NOT”, “RECOMMENDED”, “MAY”, and “OPTIONAL” in this document are to be interpreted as described in RFC 2119.

A conforming processor is a JSON-LD 1.1 processor that additionally interprets the terms defined in this specification according to the processing rules stated herein.

A non-extended processor is a standard JSON-LD 1.1 processor. Such processors MUST treat jsonld-ex terms as ordinary properties mapped by the context file, preserving them without semantic interpretation.

1.3 Notation

In the definitions below:

“Value object” refers to a JSON-LD node of the form {"@value": ..., ...}.
“Node object” refers to a JSON-LD node that may contain @id, @type, and properties.
XSD datatypes use the prefix xsd: for http://www.w3.org/2001/XMLSchema#.

2. Classes

2.1 jex:Opinion

Property	Value
IRI	`https://w3id.org/jsonld-ex/Opinion`
Subclass of	`rdfs:Resource`

An opinion ω = (b, d, u, a) per Jøsang’s Subjective Logic (2016), representing a nuanced belief state that distinguishes between evidence for a proposition, evidence against it, and absence of evidence.

An Opinion node MUST contain exactly the properties jex:belief, jex:disbelief, jex:uncertainty, and jex:baseRate, satisfying the constraint b + d + u = 1.

See the Confidence Algebra specification for the full formal treatment.

Example:

{
  "@type": "jex:Opinion",
  "jex:belief": 0.70,
  "jex:disbelief": 0.10,
  "jex:uncertainty": 0.20,
  "jex:baseRate": 0.50
}

3. Core Annotation Properties

These properties attach AI/ML provenance metadata to value objects. They are the most commonly used jsonld-ex terms.

3.1 jex:confidence

Property	Value
IRI	`https://w3id.org/jsonld-ex/confidence`
Compact form	`@confidence`
Type	`xsd:double`
Domain	Value object
Range	`[0.0, 1.0]`

The scalar confidence or certainty of an assertion. A value of 1.0 indicates absolute certainty; 0.0 indicates no confidence.

This is a lossy projection of the richer Opinion representation. When an Opinion is available, the projected probability P(ω) = b + a·u provides the equivalent scalar. See the Confidence Algebra specification for the relationship between scalar confidence and opinions.

Processing rules:

Processors MUST validate that @confidence is a finite number in [0.0, 1.0].
Processors MUST reject NaN, Infinity, -Infinity, booleans, and non-numeric values.
@confidence SHOULD appear on value objects (nodes containing @value).
During expansion, @confidence maps to https://w3id.org/jsonld-ex/confidence.

Example:

{
  "name": {
    "@value": "Jane Doe",
    "@confidence": 0.95
  }
}

3.2 jex:source

Property	Value
IRI	`https://w3id.org/jsonld-ex/source`
Compact form	`@source`
Type	`@id` (IRI)
Domain	Value object
Range	IRI identifying a system, model, or agent

Identifies the system, model, or agent that produced the assertion. This is the primary provenance link, analogous to prov:wasAttributedTo in PROV-O.

Processing rules:

The value SHOULD be a dereferenceable IRI identifying the producing system.
When converting to PROV-O, @source maps to a prov:SoftwareAgent via prov:wasAttributedTo.

Example:

{
  "name": {
    "@value": "Jane Doe",
    "@confidence": 0.95,
    "@source": "https://model.example.org/ner-v4"
  }
}

3.3 jex:extractedAt

Property	Value
IRI	`https://w3id.org/jsonld-ex/extractedAt`
Compact form	`@extractedAt`
Type	`xsd:dateTime`
Domain	Value object
Range	ISO 8601 timestamp

The timestamp at which the value was extracted or generated. Corresponds to prov:generatedAtTime in PROV-O.

Processing rules:

The value MUST be a valid ISO 8601 date-time string.
Processors SHOULD accept both Z and ±HH:MM timezone suffixes.
Date-only values (YYYY-MM-DD) are permitted and interpreted as midnight UTC.

Example:

{
  "name": {
    "@value": "Jane Doe",
    "@extractedAt": "2026-01-15T10:30:00Z"
  }
}

3.4 jex:method

Property	Value
IRI	`https://w3id.org/jsonld-ex/method`
Compact form	`@method`
Type	`xsd:string`
Domain	Value object
Range	Free-text description of the extraction method

Describes the method used to produce the assertion (e.g., “NER”, “classification”, “regression”, “IMU-6axis-classification”).

Processing rules:

The value MUST be a non-empty string.
Processors MAY use this value for display, filtering, or provenance reporting.

Example:

{
  "name": {
    "@value": "Jane Doe",
    "@method": "NER"
  }
}

3.5 jex:humanVerified

Property	Value
IRI	`https://w3id.org/jsonld-ex/humanVerified`
Compact form	`@humanVerified`
Type	`xsd:boolean`
Domain	Value object
Range	`true` or `false`

Indicates whether a human has reviewed and verified the assertion. This is critical for human-in-the-loop ML pipelines where automated extractions require manual validation.

Processing rules:

The value MUST be a JSON boolean (true or false).
Processors MUST NOT coerce strings or numbers to booleans.

Example:

{
  "name": {
    "@value": "Jane Doe",
    "@confidence": 0.98,
    "@humanVerified": true
  }
}

4. Multimodal Properties

These properties support provenance tracking for multimodal content (images, audio, video, documents).

4.1 jex:mediaType

Property	Value
IRI	`https://w3id.org/jsonld-ex/mediaType`
Compact form	`@mediaType`
Type	`xsd:string`
Domain	Value object
Range	IANA media type (e.g., `image/png`, `audio/wav`)

The IANA media type of the source content from which the value was derived.

Processing rules:

The value SHOULD conform to the IANA media type registry format (type/subtype).

Example:

{
  "caption": {
    "@value": "A cat sitting on a windowsill",
    "@mediaType": "image/jpeg",
    "@contentUrl": "https://example.org/images/cat.jpg"
  }
}

4.2 jex:contentUrl

Property	Value
IRI	`https://w3id.org/jsonld-ex/contentUrl`
Compact form	`@contentUrl`
Type	`@id` (IRI)
Domain	Value object
Range	IRI of the source content

A dereferenceable IRI pointing to the original content from which the value was derived.

4.3 jex:contentHash

Property	Value
IRI	`https://w3id.org/jsonld-ex/contentHash`
Compact form	`@contentHash`
Type	`xsd:string`
Domain	Value object
Range	Hash string in `algorithm-base64` format

A cryptographic hash of the source content, enabling integrity verification. Uses the same algorithm-base64 format as @integrity (see Security).

Example:

{
  "caption": {
    "@value": "A cat sitting on a windowsill",
    "@contentHash": "sha256-n4bQgYhMfWWaL+qgxVrQFaO/TxsrC4Is0V1sFbDwCgg="
  }
}

5. Translation Properties

These properties track provenance for machine-translated content.

5.1 jex:translatedFrom

Property	Value
IRI	`https://w3id.org/jsonld-ex/translatedFrom`
Compact form	`@translatedFrom`
Type	`xsd:string`
Domain	Value object
Range	BCP 47 language tag (e.g., `en`, `zh-Hans`, `fr-FR`)

The language of the original text before translation.

Example:

{
  "description": {
    "@value": "Ein rotes Auto",
    "@language": "de",
    "@translatedFrom": "en",
    "@translationModel": "https://model.example.org/nmt-en-de-v3"
  }
}

5.2 jex:translationModel

Property	Value
IRI	`https://w3id.org/jsonld-ex/translationModel`
Compact form	`@translationModel`
Type	`xsd:string`
Domain	Value object
Range	Identifier or IRI of the translation model

Identifies the machine translation model or service used.

6. IoT and Sensor Properties

These properties support sensor data provenance and measurement metadata, designed for interoperability with the W3C SSN/SOSA ontology.

6.1 jex:measurementUncertainty

Property	Value
IRI	`https://w3id.org/jsonld-ex/measurementUncertainty`
Compact form	`@measurementUncertainty`
Type	`xsd:double`
Domain	Value object
Range	Non-negative number

The measurement uncertainty (error margin) of a sensor reading. This is distinct from @confidence, which represents epistemic certainty about an assertion; @measurementUncertainty represents the physical precision of a measurement instrument.

Processing rules:

The value MUST be a non-negative finite number.
The units of uncertainty match the units of the measured value.
Maps to sosa:resultQuality in SSN/SOSA.

Example:

{
  "temperature": {
    "@value": 36.7,
    "@measurementUncertainty": 0.2,
    "@unit": "celsius"
  }
}

6.2 jex:unit

Property	Value
IRI	`https://w3id.org/jsonld-ex/unit`
Compact form	`@unit`
Type	`xsd:string`
Domain	Value object
Range	Unit identifier (e.g., `celsius`, `kg`, `m/s`)

The unit of measurement for a numeric value. Processors SHOULD use standardized unit identifiers (e.g., UCUM codes) where possible.

7. Derivation Properties

7.1 jex:derivedFrom

Property	Value
IRI	`https://w3id.org/jsonld-ex/derivedFrom`
Compact form	`@derivedFrom`
Type	`@id` or array of `@id`
Domain	Value object
Range	IRI(s) of source entities or assertions

Links a derived assertion to its source(s). Corresponds to prov:wasDerivedFrom in PROV-O. When multiple sources contributed, the value is an array of IRIs.

Example:

{
  "summary": {
    "@value": "Patient shows improvement in mobility.",
    "@derivedFrom": [
      "https://example.org/observation/001",
      "https://example.org/observation/002"
    ],
    "@method": "LLM-summarization"
  }
}

8. Aggregation Properties

These properties describe how a value was produced by aggregating multiple observations.

8.1 jex:aggregationMethod

Property	Value
IRI	`https://w3id.org/jsonld-ex/aggregationMethod`
Compact form	`@aggregationMethod`
Type	`xsd:string`
Domain	Value object
Range	Aggregation method identifier (e.g., `mean`, `median`, `max`, `min`, `sum`, `count`)

The statistical method used to aggregate multiple observations into this value.

8.2 jex:aggregationWindow

Property	Value
IRI	`https://w3id.org/jsonld-ex/aggregationWindow`
Compact form	`@aggregationWindow`
Type	`xsd:string`
Domain	Value object
Range	ISO 8601 duration (e.g., `PT1H`, `P1D`) or descriptive string

The time window over which observations were aggregated.

8.3 jex:aggregationCount

Property	Value
IRI	`https://w3id.org/jsonld-ex/aggregationCount`
Compact form	`@aggregationCount`
Type	`xsd:integer`
Domain	Value object
Range	Positive integer

The number of individual observations that were aggregated to produce this value.

Example:

{
  "averageHeartRate": {
    "@value": 72,
    "@aggregationMethod": "mean",
    "@aggregationWindow": "PT1H",
    "@aggregationCount": 360,
    "@unit": "bpm"
  }
}

9. Calibration Properties

These properties record the calibration state of a sensor or measurement instrument.

9.1 jex:calibratedAt

Property	Value
IRI	`https://w3id.org/jsonld-ex/calibratedAt`
Compact form	`@calibratedAt`
Type	`xsd:dateTime`
Domain	Value object
Range	ISO 8601 timestamp

The timestamp of the most recent calibration of the instrument that produced this value.

9.2 jex:calibrationMethod

Property	Value
IRI	`https://w3id.org/jsonld-ex/calibrationMethod`
Compact form	`@calibrationMethod`
Type	`xsd:string`
Domain	Value object
Range	Free-text description of the calibration procedure

9.3 jex:calibrationAuthority

Property	Value
IRI	`https://w3id.org/jsonld-ex/calibrationAuthority`
Compact form	`@calibrationAuthority`
Type	`xsd:string`
Domain	Value object
Range	Name or IRI of the calibrating entity

The organization or entity that performed the calibration.

Example:

{
  "temperature": {
    "@value": 36.7,
    "@calibratedAt": "2025-12-01T09:00:00Z",
    "@calibrationMethod": "two-point water bath",
    "@calibrationAuthority": "NIST"
  }
}

10. Delegation Properties

10.1 jex:delegatedBy

Property	Value
IRI	`https://w3id.org/jsonld-ex/delegatedBy`
Compact form	`@delegatedBy`
Type	`@id` or array of `@id`
Domain	Value object
Range	IRI(s) identifying delegating agents

Records the chain of delegation for an assertion. When agent A delegates to agent B which produces the assertion, the delegation chain is recorded as ["agentA-iri", "agentB-iri"]. Corresponds to prov:actedOnBehalfOf in PROV-O.

Example:

{
  "diagnosis": {
    "@value": "hypertension",
    "@confidence": 0.82,
    "@source": "https://model.example.org/clinical-v2",
    "@delegatedBy": "https://hospital.example.org/dr-smith"
  }
}

11. Invalidation Properties

These properties mark an assertion as no longer valid.

11.1 jex:invalidatedAt

Property	Value
IRI	`https://w3id.org/jsonld-ex/invalidatedAt`
Compact form	`@invalidatedAt`
Type	`xsd:dateTime`
Domain	Value object
Range	ISO 8601 timestamp

The timestamp at which the assertion was invalidated. Corresponds to prov:invalidatedAtTime in PROV-O.

Processing rules:

When @invalidatedAt is present, processors SHOULD treat the assertion as retracted.
The filter_by_confidence function supports an exclude_invalidated parameter that skips nodes with this property.

11.2 jex:invalidationReason

Property	Value
IRI	`https://w3id.org/jsonld-ex/invalidationReason`
Compact form	`@invalidationReason`
Type	`xsd:string`
Domain	Value object
Range	Free-text explanation

A human-readable explanation of why the assertion was invalidated.

Example:

{
  "diagnosis": {
    "@value": "hypertension",
    "@confidence": 0.82,
    "@invalidatedAt": "2026-02-01T14:00:00Z",
    "@invalidationReason": "Superseded by updated lab results"
  }
}

12. Temporal Properties

These properties enable time-aware assertions. See the Temporal specification for full query and diff semantics.

12.1 jex:validFrom

Property	Value
IRI	`https://w3id.org/jsonld-ex/validFrom`
Compact form	`@validFrom`
Type	`xsd:dateTime`
Domain	Value object or node object
Range	ISO 8601 timestamp

The timestamp at which the assertion becomes true. Before this time, the assertion is not yet in effect.

Processing rules:

When both @validFrom and @validUntil are present, processors MUST validate that @validFrom ≤ @validUntil.

12.2 jex:validUntil

Property	Value
IRI	`https://w3id.org/jsonld-ex/validUntil`
Compact form	`@validUntil`
Type	`xsd:dateTime`
Domain	Value object or node object
Range	ISO 8601 timestamp

The timestamp at which the assertion ceases to be true. After this time, the assertion has expired.

12.3 jex:asOf

Property	Value
IRI	`https://w3id.org/jsonld-ex/asOf`
Compact form	`@asOf`
Type	`xsd:dateTime`
Domain	Value object or node object
Range	ISO 8601 timestamp

The point in time at which the assertion was known or observed to hold. This is distinct from @extractedAt (when the value was produced) and @validFrom (when the assertion becomes effective). @asOf records the observation time — “as of this moment, this was true.”

Example:

{
  "jobTitle": {
    "@value": "Senior Engineer",
    "@validFrom": "2024-01-01",
    "@validUntil": "2025-12-31",
    "@asOf": "2025-06-15T12:00:00Z"
  }
}

13. Opinion Properties

These properties represent the components of a Subjective Logic opinion. They appear on nodes of type jex:Opinion. See the Confidence Algebra specification for the complete formal treatment.

13.1 jex:belief

Property	Value
IRI	`https://w3id.org/jsonld-ex/belief`
Compact form	`belief` (within Opinion context)
Type	`xsd:double`
Domain	`jex:Opinion`
Range	`[0.0, 1.0]`

The degree of belief (evidence FOR the proposition). Denoted b in the opinion tuple ω = (b, d, u, a).

13.2 jex:disbelief

Property	Value
IRI	`https://w3id.org/jsonld-ex/disbelief`
Compact form	`disbelief` (within Opinion context)
Type	`xsd:double`
Domain	`jex:Opinion`
Range	`[0.0, 1.0]`

The degree of disbelief (evidence AGAINST the proposition). Denoted d in the opinion tuple.

13.3 jex:uncertainty

Property	Value
IRI	`https://w3id.org/jsonld-ex/uncertainty`
Compact form	`uncertainty` (within Opinion context)
Type	`xsd:double`
Domain	`jex:Opinion`
Range	`[0.0, 1.0]`

The degree of uncertainty (absence of evidence). Denoted u in the opinion tuple.

Invariant: For any valid opinion, belief + disbelief + uncertainty = 1.

13.4 jex:baseRate

Property	Value
IRI	`https://w3id.org/jsonld-ex/baseRate`
Compact form	`baseRate` (within Opinion context)
Type	`xsd:double`
Domain	`jex:Opinion`
Range	`[0.0, 1.0]`
Default	`0.5`

The prior probability (base rate) of the proposition. Denoted a in the opinion tuple. Used to compute the projected probability: P(ω) = b + a·u.

14. Vector Properties

These properties support dense vector embeddings alongside symbolic data.

14.1 @vector (Container Type)

Property	Value
Keyword	`@vector`
Used in	Context term definitions (`@container`)

A container type indicating that a property holds a dense vector embedding (an ordered array of floating-point numbers).

Processing rules:

During expansion, vector values MUST be preserved as JSON arrays of numbers.
During compaction, vector values MUST be preserved without modification.
During RDF conversion, properties with @container: @vector MUST be excluded. Vectors are annotation-only and do not participate in the RDF graph.
During CBOR-LD encoding, vectors SHOULD use efficient binary float array encoding.

14.2 @dimensions

Property	Value
Keyword	`@dimensions`
Used in	Context term definitions (alongside `@container: @vector`)
Type	`xsd:integer`
Range	Positive integer

Specifies the expected dimensionality of a vector property. Processors SHOULD validate that the vector length matches @dimensions during expansion.

Example:

{
  "@context": {
    "embedding": {
      "@id": "https://w3id.org/jsonld-ex/embedding",
      "@container": "@vector",
      "@dimensions": 768
    }
  },
  "@type": "Product",
  "name": "Widget",
  "embedding": [0.123, -0.456, 0.789]
}

15. Security Properties

See the Security specification for the complete threat model and processing algorithms.

15.1 @integrity

Property	Value
Keyword	`@integrity`
Used in	Context references
Type	`xsd:string`
Format	`algorithm-base64hash`

A cryptographic hash of a context document, enabling integrity verification before use. Prevents context injection attacks via DNS poisoning or man-in-the-middle modification.

Supported algorithms: sha256, sha384, sha512.

Processing rules:

The format MUST be algorithm-base64hash where algorithm is one of the supported algorithms and base64hash is the Base64-encoded digest of the context content.
Processors MUST compute the hash of the retrieved context and compare it to the declared value.
If the hashes do not match, processors MUST reject the context (fail-closed behavior).
Processors MUST NOT fall back to using the context without verification when @integrity is declared.

Example:

{
  "@context": {
    "@id": "https://schema.org/",
    "@integrity": "sha256-n4bQgYhMfWWaL+qgxVrQFaO/TxsrC4Is0V1sFbDwCgg="
  }
}

16. Validation Properties

These properties define shape-based constraints for JSON-LD documents. See the Validation specification for the complete formal semantics, inheritance resolution, and relationship to SHACL.

16.1 @shape

Property	Value
Keyword	`@shape`
Type	Object (shape definition) or nested shape reference

A shape definition constraining the structure and values of a JSON-LD node. Shapes contain property constraints using the keywords defined below. When used as a property constraint (nested), validates that the property value conforms to the inner shape.

16.2 @required

Property	Value
Keyword	`@required`
Type	`xsd:boolean`
Default	`false`

When true, the property MUST be present in the node and MUST NOT have a null or absent value.

SHACL equivalent: sh:minCount 1

16.3 @extends

Property	Value
Keyword	`@extends`
Type	String (shape name), inline shape object, or array thereof

Specifies one or more parent shapes from which to inherit constraints. Child constraints override parent constraints for the same property. Resolution uses the shape_registry parameter.

Processing rules:

Circular inheritance MUST be detected and prevented.
Multiple parents are merged left-to-right, with later parents overriding earlier ones.
The child shape’s own constraints override all inherited constraints.

16.4 @type (in validation context)

When used within a shape property constraint, @type specifies the expected XSD datatype of the value. Supported types: xsd:string, xsd:integer, xsd:double, xsd:float, xsd:decimal, xsd:boolean.

SHACL equivalent: sh:datatype

16.5 @minimum

Property	Value
Keyword	`@minimum`
Type	Numeric

The value MUST be greater than or equal to this number. Applies only to numeric values (booleans excluded).

SHACL equivalent: sh:minInclusive

16.6 @maximum

Property	Value
Keyword	`@maximum`
Type	Numeric

The value MUST be less than or equal to this number.

SHACL equivalent: sh:maxInclusive

16.7 @minLength

Property	Value
Keyword	`@minLength`
Type	`xsd:integer`

The string value MUST have at least this many characters.

SHACL equivalent: sh:minLength

16.8 @maxLength

Property	Value
Keyword	`@maxLength`
Type	`xsd:integer`

The string value MUST have at most this many characters.

SHACL equivalent: sh:maxLength

16.9 @pattern

Property	Value
Keyword	`@pattern`
Type	`xsd:string` (regular expression)

The string value MUST match this regular expression (searched, not full-match). Uses standard regex syntax.

SHACL equivalent: sh:pattern

16.10 @in

Property	Value
Keyword	`@in`
Type	Array

The value MUST be a member of the specified array (enumeration constraint).

SHACL equivalent: sh:in

16.11 @minCount

Property	Value
Keyword	`@minCount`
Type	`xsd:integer`

The property MUST have at least this many values. For absent properties, the count is 0; for a single value, the count is 1; for an array, the count is the array length.

SHACL equivalent: sh:minCount

16.12 @maxCount

Property	Value
Keyword	`@maxCount`
Type	`xsd:integer`

The property MUST have at most this many values.

SHACL equivalent: sh:maxCount

16.13 @severity

Property	Value
Keyword	`@severity`
Type	`xsd:string`
Range	`"error"`, `"warning"`, `"info"`
Default	`"error"`

Controls the severity of a constraint violation. Violations at "warning" or "info" severity are reported as warnings rather than errors and do not cause validation failure.

SHACL equivalent: sh:severity

16.14 @or

Property	Value
Keyword	`@or`
Type	Array of constraint objects

The value MUST satisfy at least one of the constraint branches (logical disjunction).

SHACL equivalent: sh:or

16.15 @and

Property	Value
Keyword	`@and`
Type	Array of constraint objects

The value MUST satisfy all of the constraint branches (logical conjunction).

SHACL equivalent: sh:and

16.16 @not

Property	Value
Keyword	`@not`
Type	Constraint object

The value MUST NOT satisfy the inner constraint (logical negation).

SHACL equivalent: sh:not

16.17 @if / @then / @else

Property	Value
Keywords	`@if`, `@then`, `@else`
Type	Constraint objects

Conditional constraint evaluation. If the value satisfies @if, it MUST also satisfy @then. If it does not satisfy @if, it MUST satisfy @else (if present). When @else is absent and @if is not met, the constraint is vacuously true.

Example:

{
  "age": {
    "@if": {"@minimum": 18},
    "@then": {"@in": ["adult", "senior"]},
    "@else": {"@in": ["minor"]}
  }
}

16.18 @lessThan

Property	Value
Keyword	`@lessThan`
Type	`xsd:string` (property name)

Cross-property constraint: the value MUST be strictly less than the value of the named sibling property.

SHACL equivalent: sh:lessThan

16.19 @lessThanOrEquals

Property	Value
Keyword	`@lessThanOrEquals`
Type	`xsd:string` (property name)

Cross-property constraint: the value MUST be less than or equal to the value of the named sibling property.

SHACL equivalent: sh:lessThanOrEquals

16.20 @equals

Property	Value
Keyword	`@equals`
Type	`xsd:string` (property name)

Cross-property constraint: the value MUST be equal to the value of the named sibling property.

SHACL equivalent: sh:equals

16.21 @disjoint

Property	Value
Keyword	`@disjoint`
Type	`xsd:string` (property name)

Cross-property constraint: the value MUST differ from the value of the named sibling property.

SHACL equivalent: sh:disjoint

16.22 Validation Shape Example

{
  "@shape": {
    "@type": "Person",
    "name": {
      "@required": true,
      "@type": "xsd:string",
      "@minLength": 1
    },
    "email": {
      "@pattern": "^[^@]+@[^@]+$"
    },
    "age": {
      "@type": "xsd:integer",
      "@minimum": 0,
      "@maximum": 150
    },
    "startDate": {
      "@lessThan": "endDate"
    }
  }
}

17. Summary Table

#	Term	Compact Form	Type	Category
1	`jex:confidence`	`@confidence`	`xsd:double`	Core
2	`jex:source`	`@source`	`@id`	Core
3	`jex:extractedAt`	`@extractedAt`	`xsd:dateTime`	Core
4	`jex:method`	`@method`	`xsd:string`	Core
5	`jex:humanVerified`	`@humanVerified`	`xsd:boolean`	Core
6	`jex:mediaType`	`@mediaType`	`xsd:string`	Multimodal
7	`jex:contentUrl`	`@contentUrl`	`@id`	Multimodal
8	`jex:contentHash`	`@contentHash`	`xsd:string`	Multimodal
9	`jex:translatedFrom`	`@translatedFrom`	`xsd:string`	Translation
10	`jex:translationModel`	`@translationModel`	`xsd:string`	Translation
11	`jex:measurementUncertainty`	`@measurementUncertainty`	`xsd:double`	IoT/Sensor
12	`jex:unit`	`@unit`	`xsd:string`	IoT/Sensor
13	`jex:derivedFrom`	`@derivedFrom`	`@id` / array	Derivation
14	`jex:aggregationMethod`	`@aggregationMethod`	`xsd:string`	Aggregation
15	`jex:aggregationWindow`	`@aggregationWindow`	`xsd:string`	Aggregation
16	`jex:aggregationCount`	`@aggregationCount`	`xsd:integer`	Aggregation
17	`jex:calibratedAt`	`@calibratedAt`	`xsd:dateTime`	Calibration
18	`jex:calibrationMethod`	`@calibrationMethod`	`xsd:string`	Calibration
19	`jex:calibrationAuthority`	`@calibrationAuthority`	`xsd:string`	Calibration
20	`jex:delegatedBy`	`@delegatedBy`	`@id` / array	Delegation
21	`jex:invalidatedAt`	`@invalidatedAt`	`xsd:dateTime`	Invalidation
22	`jex:invalidationReason`	`@invalidationReason`	`xsd:string`	Invalidation
23	`jex:validFrom`	`@validFrom`	`xsd:dateTime`	Temporal
24	`jex:validUntil`	`@validUntil`	`xsd:dateTime`	Temporal
25	`jex:asOf`	`@asOf`	`xsd:dateTime`	Temporal
26	`jex:belief`	`belief`	`xsd:double`	Opinion
27	`jex:disbelief`	`disbelief`	`xsd:double`	Opinion
28	`jex:uncertainty`	`uncertainty`	`xsd:double`	Opinion
29	`jex:baseRate`	`baseRate`	`xsd:double`	Opinion
30	`jex:Opinion`	`Opinion`	Class	Opinion
31	`@vector`	`@vector`	Container type	Vector
32	`@dimensions`	`@dimensions`	`xsd:integer`	Vector
33	`@integrity`	`@integrity`	`xsd:string`	Security
34	`@shape`	`@shape`	Object	Validation
35	`@required`	`@required`	`xsd:boolean`	Validation
36	`@extends`	`@extends`	String / Object	Validation
37	`@minimum`	`@minimum`	Numeric	Validation
38	`@maximum`	`@maximum`	Numeric	Validation
39	`@minLength`	`@minLength`	`xsd:integer`	Validation
40	`@maxLength`	`@maxLength`	`xsd:integer`	Validation
41	`@pattern`	`@pattern`	`xsd:string`	Validation
42	`@in`	`@in`	Array	Validation
43	`@minCount`	`@minCount`	`xsd:integer`	Validation
44	`@maxCount`	`@maxCount`	`xsd:integer`	Validation
45	`@severity`	`@severity`	`xsd:string`	Validation
46	`@or`	`@or`	Array	Validation
47	`@and`	`@and`	Array	Validation
48	`@not`	`@not`	Object	Validation
49	`@if` / `@then` / `@else`	`@if` / `@then` / `@else`	Object	Validation
50	`@lessThan`	`@lessThan`	`xsd:string`	Validation
51	`@lessThanOrEquals`	`@lessThanOrEquals`	`xsd:string`	Validation
52	`@equals`	`@equals`	`xsd:string`	Validation
53	`@disjoint`	`@disjoint`	`xsd:string`	Validation

18. References

Jøsang, A. (2016). Subjective Logic: A Formalism for Reasoning Under Uncertainty. Springer.
W3C. (2020). JSON-LD 1.1. W3C Recommendation. https://www.w3.org/TR/json-ld11/
W3C. (2017). PROV-O: The PROV Ontology. W3C Recommendation. https://www.w3.org/TR/prov-o/
W3C. (2017). SHACL: Shapes Constraint Language. W3C Recommendation. https://www.w3.org/TR/shacl/
W3C. (2017). SSN/SOSA: Semantic Sensor Network Ontology. W3C Recommendation. https://www.w3.org/TR/vocab-ssn/
IETF. (1997). RFC 2119: Key words for use in RFCs to Indicate Requirement Levels. https://www.rfc-editor.org/rfc/rfc2119