XML schemas

Define form fields and data contracts directly in XML. This standalone dialect describes JSON Schema; it does not change the validation engine. Embed its schema root inside an authoring node that accepts schemas: integration configuration-schema, Action input-schema, config-schema and output-schema, container json-schema, EdgeApp config-schema, workflow input-schema, workspace handler input/output, or journey schema.

A configuration form

<config-schema>
  <schema xmlns="urn:cococo:json-schema:1" type="object" additional-properties="false">
    <property name="endpoint" type="string" format="uri" required="true">
      <description>Service endpoint</description>
    </property>
    <property name="token" type="string" input-type="password" required="true"/>
    <property name="device" type="string" related-resource="device" resource-value-field="id"/>
    <property name="retries" type="integer" minimum="0">
      <default type="integer">3</default>
    </property>
    <property-order><name name="endpoint"/><name name="token"/><name name="device"/><name name="retries"/></property-order>
  </schema>
</config-schema>

A prefix such as s:schema with xmlns:s="urn:cococo:json-schema:1" is equivalent. Namespace declarations may be placed on an ancestor. Schema elements use that namespace; ordinary resource elements keep their own vocabulary.

Constraints and composition

String constraints are attributes: anchor, comment, content-encoding, content-media-type, description, dynamic-anchor, dynamic-ref, format, id, meta-schema, pattern, ref, title. Numeric constraints: exclusive-maximum, exclusive-minimum, max-contains, max-items, max-length, max-properties, maximum, min-contains, min-items, min-length, min-properties, minimum, multiple-of. Boolean attributes: deprecated, read-only, unique-items, write-only. type="string null" declares a union; boolean="false" is a schema that accepts nothing.

Use property name="…", pattern-property name="…", definition name="…" and dependent-schema name="…" for named schemas. Optional properties, pattern-properties, definitions and dependent-schemas containers group their corresponding named children and preserve empty maps. required-properties contains name children and can represent an empty required list. required="true" on a property adds its name to the enclosing required list; <required name="…"/> also supports required names without a property declaration.

additional-properties, contains, content-schema, else, if, items, not, property-names, then, unevaluated-items, unevaluated-properties contain schema constraints directly. They also accept boolean attribute forms, such as additional-properties="false". all-of, any-of, one-of, prefix-items contain ordered <schema> children. References retain JSON Pointer syntax: ref="#/$defs/entry". The host's reference rules still apply.

<dependent-required name="field"><name name="other"/></dependent-required> describes a dependency. <vocabulary uri="…" required="true"/> declares a JSON Schema vocabulary.

Values without type guessing

Defaults, constants, examples and enum choices use explicit types. A string 0012 remains a string; null, false and zero stay distinct.

<schema xmlns="urn:cococo:json-schema:1" type="string">
  <enum><value type="string">small</value><value type="string">large</value></enum>
  <default type="string">small</default>
  <enum-labels><value name="small" type="string">Small format</value><value name="large" type="string">Large format</value></enum-labels>
</schema>

default, const, and the platform example annotation take type="string|integer|number|boolean|null|object|array". Object values contain <value name="…" type="…">; arrays contain unnamed <value> children. enum and examples contain typed values. Strings preserve whitespace. Use XML escaping for < and &; CDATA is also available for literal text inside a typed value.

Form and platform annotations

These native names compile to the existing annotations, so forms, resource lookups, secret extraction and expression tooling see the same contract.

XML name	JSON annotation	Value kind	Purpose
input-type	x-input-type	string	Form input type; password marks a secret, text requests a text input.
editor	x-editor	string	Form editor, such as code.
editor-language	x-editorLanguage	string	Language for the code editor.
related-resource	x-relatedResource	string	Resource used by a form lookup.
resource-value-field	x-resourceValueField	string	Field returned by the resource lookup.
property-order	x-propertyOrder	strings	Explicit form field order; use one name child per property.
supports-expression	x-supportsExpression	boolean	Whether expressions are permitted.
expression-format	x-expressionFormat	string	Expression syntax: path, template or predicate.
expression-depth	x-expressionDepth	integer	Depth to which expression support is inherited.
expression-container-only	x-expressionContainerOnly	boolean	Expressions belong in descendants, not the container itself.
expression-evaluation	x-expressionEvaluation	string	Expression evaluation mode.
expression-result-schema	x-expressionResultSchema	schema	Expected result schema for an expression.
dynamic-schema	x-dynamicSchema	string	Resource and field providing a dynamic form schema.
query-parameter-bindings	x-queryParameterBindings	string	Query field whose parameters populate bindings.
ai-hint	x-aiHint	string	Author guidance for AI-assisted use.
node-type	x-nodeType	string	Workflow node type identity.
icon	x-icon	string	Presentation icon.
group	x-group	string	Presentation group.
example	x-example	value	An example value.
enum-labels	x-enum-labels	stringMap	Human-readable labels keyed by enum value.
enum-values	x-enum-values	valueMap	Structured values keyed by enum value.
dimension	x-dimension	string	Product-template dimension; subject to host validation.
applies-to	x-applies-to	strings	Product-template components to which this property applies.
visible-when	x-visibleWhen	valueMap	Workflow visibility condition with field and equals entries.
visible-when-values	x-visible-when	valueMap	Product-option visibility conditions keyed by property name.
placeholder	x-placeholder	string	Placeholder shown in the field.
unit	x-unit	string	Unit suffix displayed alongside the value.
secret	x-secret	boolean	Credential hint for consumers supporting workflow secret annotations; integration secrets use input-type=password.
binding	x-binding	boolean	Workspace field accepts a data binding.
items-from	x-itemsFrom	string	Sibling array binding used for item-relative fields.
journey-picker	x-journeyPicker	boolean	Select a published journey.
suggested-enum	x-enum	values	Suggested values used by workflow configuration editors.
category	x-category	string	Workflow palette category identifier.
categories	x-categories	values	Ordered workflow palette category descriptors.
target	x-target	string	Product-option target kind.
target-field	x-target-field	string	Product-option target field.
passthrough	x-passthrough	boolean	Output preserves its input shape.

Scalar annotations are attributes, or text children when longer prose is easier to read. Name lists accept whitespace-separated attributes such as property-order="endpoint token device"; for names containing whitespace, use <name name="…"/> children. Maps use typed <value name="…" type="…"> children. expression-result-schema contains schema constraints directly. An annotation only affects the host consumers that implement it; product-template annotations do not become integration behavior merely by being present.

Compatibility and validation

Existing JSON text and JSON inside CDATA remain accepted in schema-bearing nodes. Use exactly one representation: JSON text/CDATA, or one XML schema root. Mixing them, duplicate keywords and unknown XML names are errors. Authored source is preserved. Generated XML prefers native schemas; a serializer must retain JSON rather than drop a keyword it cannot represent.

Host restrictions remain in force. Workspace handler contracts intentionally accept a narrower schema vocabulary; XML does not enable references, unrestricted alternatives or annotations at that boundary. Integration schemas retain local-reference restrictions. XML parsing prohibits DTDs and external entities, and existing source, nesting and output limits still apply.