Process Execution Conformance — Scope

Process Execution Conformance is BPMN 2.0.2 §2.3, and it has two requirements, addressed to "the tool":

• §2.3.1 Execution Semantics — the tool "MUST fully support and interpret the operational semantics and Activity life-cycle"; non-operational elements "MAY be ignored".
• §2.3.2 Import of Process Diagrams — the tool "MUST support import of BPMN Process diagram types including its definitional Collaboration".

A library is not a tool. gobpm ships as an embeddable library and, built on it, the gobpm-server product (SAD-001 §2, §14). §2.3.1 is the library's target and the subject of this document. §2.3.2 belongs to the server, through the converter — so the import-side element coverage is tracked with that work, not here.

This list enumerates §13's operational elements plus the supporting classes they need. Clause 13 animates process instantiation and termination (§13.2), activities (§13.3, including Sub-Process, Call Activity, Ad-Hoc, Loop and Multi-Instance), all five gateways (§13.4) and every event position (§13.5, including boundary, event sub-process and compensation). The remaining entries fall into two further tiers, and the element-coverage suite proves each differently:

Tier	What it is	How coverage is proven
Operational	animated by Clause 13 — activities, gateways, events, flows, containers, markers	a suite-owned scenario executes it
Supporting	consumed by Clause 13 to express the above — data, foundation, correlation, operations, human interaction	a guard-checked binding to the tests that exercise it
Model-only	carried but never executed — Lane/LaneSet	the type exists and survives a round-trip; execution must ignore it

The first distinction is the standard's own (§13 animates, §8/§10 supply). The third exists because "non-operational" governs execution, not representation: §2.3.1 permits ignoring such elements at run time, while §2.3.2 and ADR-024 §2.8 require the model to hold them.

Correction (2026-08-02). Earlier revisions of this document cited "§2.1.2" for Process Execution Conformance and derived the element set from the Common Executable Subclass ("§2.1.3"). Neither clause exists — §2.1 is General, §2.2 is Process Modeling Conformance — and Common Executable is a sub-class of Modeling conformance (§2.2.1) for tools that emit executable models, mandating XML Schema, WSDL and XPath, none of which this engine uses. The mis-citation is traceable to §2.1's own cross-reference paragraph, which is off by one against the spec's headings. Consequence: ComplexGateway is no longer an "extension" — §13.4.5 gives it complete operational semantics, so §2.3.1 always required it. Its workflow-pattern value (Structured Discriminator WCP-9, Blocking Discriminator WCP-28, Structured Partial Join WCP-30, Blocking Partial Join WCP-31) is a reason it is useful, not a reason it is optional.

In scope

Process container

Element	bpmn-moddle type	Notes
Process	Process	Top-level executable process (isExecutable=true)
SubProcess	SubProcess	Embedded sub-process; also Event Sub-Process when triggeredByEvent=true
Transaction	Transaction	Sub-process with ACID-like semantics, cancel/compensation triggers
AdHocSubProcess	AdHocSubProcess	Unordered activity set with completion condition
CallActivity	CallActivity	Invokes a reusable CallableElement
Lane / LaneSet	Lane, LaneSet	Model-only — carried, never executed. §2.3.1 lets execution ignore it (no token semantics); §2.3.2 obliges an importer to preserve it, and a model that cannot hold it cannot export it back (ADR-024 §2.8 semantic round-trip).

Activities

Element	bpmn-moddle type	Notes
Task (abstract)	Task	Base for typed tasks
ServiceTask	ServiceTask	Operation invocation
UserTask	UserTask	Human task with form
ManualTask	ManualTask	Out-of-system task, no engine action
ScriptTask	ScriptTask	Inline script execution
BusinessRuleTask	BusinessRuleTask	DMN / rule engine call
SendTask	SendTask	Message throw
ReceiveTask	ReceiveTask	Message catch

Markers (on activities)

Element	bpmn-moddle type	Notes
StandardLoopCharacteristics	StandardLoopCharacteristics	Sequential loop with test condition
MultiInstanceLoopCharacteristics	MultiInstanceLoopCharacteristics	Sequential or parallel MI with cardinality / collection
ComplexBehaviorDefinition	ComplexBehaviorDefinition	Custom MI completion / event handling

Events

Element	bpmn-moddle type	Position
StartEvent	StartEvent	Process start, top-level or event-sub-process
IntermediateCatchEvent	IntermediateCatchEvent	Inline wait
IntermediateThrowEvent	IntermediateThrowEvent	Inline emit
EndEvent	EndEvent	Process / sub-process termination
BoundaryEvent	BoundaryEvent	Attached to activity (interrupting + non-interrupting via cancelActivity)
ImplicitThrowEvent	ImplicitThrowEvent	Implicit throw at process end (rarely used directly)

Event definitions (subtypes)

Element	bpmn-moddle type	Applies to
MessageEventDefinition	MessageEventDefinition	Start, IntermediateCatch, IntermediateThrow, End, Boundary
TimerEventDefinition	TimerEventDefinition	Start, IntermediateCatch, Boundary
SignalEventDefinition	SignalEventDefinition	Start, IntermediateCatch, IntermediateThrow, End, Boundary
ErrorEventDefinition	ErrorEventDefinition	Start (event sub-process only), End, Boundary
EscalationEventDefinition	EscalationEventDefinition	Start (event sub-process), IntermediateThrow, End, Boundary
CompensateEventDefinition	CompensateEventDefinition	Start (event sub-process), IntermediateThrow, End, Boundary
CancelEventDefinition	CancelEventDefinition	End, Boundary — Transaction sub-process only
ConditionalEventDefinition	ConditionalEventDefinition	Start, IntermediateCatch, Boundary
LinkEventDefinition	LinkEventDefinition	IntermediateCatch (target), IntermediateThrow (source)
TerminateEventDefinition	TerminateEventDefinition	End — terminates entire process instance
Message, Signal, Error, Escalation	(referenced item definitions)	Resolved by event definitions

Gateways

Element	bpmn-moddle type	Notes
ExclusiveGateway	ExclusiveGateway	XOR — first true condition wins
ParallelGateway	ParallelGateway	AND — all paths split / all paths sync
InclusiveGateway	InclusiveGateway	OR — all true conditions; merge waits for all expected tokens
EventBasedGateway	EventBasedGateway	Race between catching events
ComplexGateway	ComplexGateway	Activation expression over per-gate token counts, 2-phase activation/reset. Operational per §13.4.5, therefore required by §2.3.1 — not an extension (see the correction note above).

Flows

Element	bpmn-moddle type	Notes
SequenceFlow	SequenceFlow	Conditional (conditionExpression), default (referenced by default on source)
Association	Association	Compensation associations (sources to compensation handlers)

Data

Element	bpmn-moddle type	Notes
ItemDefinition	ItemDefinition	Type descriptor for data items
DataObject	DataObject	Process-scoped data
DataObjectReference	DataObjectReference	Reference to a DataObject within flow scope
DataStore	DataStore	External persistent data
DataStoreReference	DataStoreReference	Reference to a DataStore
Property	Property	Process / activity local variable
DataInput / DataOutput	DataInput, DataOutput	Activity I/O variables; a throw event's inputs and a catch event's outputs (§10.4.2); the process's declared contract (ADR-040)
DataInputAssociation	DataInputAssociation	Data flow into an activity or a throw event; a process output into an End event
DataOutputAssociation	DataOutputAssociation	Data flow out of an activity or a catch event; a Start event into a process input
InputSet / OutputSet	InputSet, OutputSet	I/O grouping with optional / while-executing semantics
InputOutputSpecification	InputOutputSpecification	Activity I/O contract
InputOutputBinding	InputOutputBinding	Binds one InputSet + one OutputSet to an Operation. Realized implicitly, with no named type — gobpm declares a single InputSet and a single OutputSet (SAD-001 §14.1), so there is no pair to select and the binding is the Operation contract itself (BindInputOnly in, Execute out). Absence of the type is a consequence of that deviation, not a gap.
Assignment	Assignment	Single from/to expression pair within a DataAssociation
DataState	DataState	Optional state qualifier on data
DataAssociation	DataAssociation	Abstract base for In/Out associations
ItemAwareElement	ItemAwareElement	Base for all data-carrying elements

Human interaction (UserTask support)

Element	bpmn-moddle type	Notes
HumanPerformer	HumanPerformer	Specialized Performer
PotentialOwner	PotentialOwner	Candidate owner expression
Performer	Performer	Generic performer
Rendering	Rendering	UI hint
Resource	Resource	Resource definition
ResourceRole	ResourceRole	Role assignment
ResourceParameter	ResourceParameter	Resource query parameter
ResourceParameterBinding	ResourceParameterBinding	Binds value to ResourceParameter
ResourceAssignmentExpression	ResourceAssignmentExpression	Expression resolving to resource(s)

Correlation (Message events)

Element	bpmn-moddle type	Notes
CorrelationKey	CorrelationKey	Named set of correlation properties
CorrelationProperty	CorrelationProperty	Property used to match messages to process instance
CorrelationPropertyRetrievalExpression	CorrelationPropertyRetrievalExpression	Extracts property value from a message
CorrelationPropertyBinding	CorrelationPropertyBinding	Binds property to subscription
CorrelationSubscription	CorrelationSubscription	Process-level subscription to a correlation key

Operations / Interfaces (Service/Send/Receive tasks)

Element	bpmn-moddle type	Notes
Interface	Interface	Operation grouping
Operation	Operation	Service operation with in/out message
EndPoint	EndPoint	Operation endpoint reference
GlobalTask / GlobalManualTask / GlobalUserTask / GlobalScriptTask / GlobalBusinessRuleTask	GlobalTask, ...	Reusable task definitions invocable via CallActivity. In scope. A GlobalTask is reuse by reference, which needs a registry of callable definitions — and the process registry is one: a global task is a callable process whose body is that one task, registered under its id and called like any other (ADR-023 §2.7). The importer builds that process; nothing on the call path distinguishes it from a called process, which is what §13.3.4 says a call is. The library also covers the same need by construction for code-built models — a Go constructor returning a configured task is a reusable definition, and a parameterizable one (task reuse).

Foundation / base types

Element	bpmn-moddle type	Notes
Definitions	Definitions	Top-level container of all root elements
BaseElement	BaseElement	Root of all BPMN elements (id, documentation, extensions)
RootElement	RootElement	Marker for top-level-only elements
FlowElement	FlowElement	Anything that appears in a process flow
FlowNode	FlowNode	Connectable element (activities, events, gateways)
FlowElementsContainer	FlowElementsContainer	Holds flowElements + laneSets (Process, SubProcess)
CallableElement	CallableElement	Invocable thing (Process, GlobalTask) — has I/O specification
Expression / FormalExpression	Expression, FormalExpression	Conditions, assignments, completion criteria
Documentation	Documentation	Human-readable annotation
Extension / ExtensionDefinition / ExtensionAttributeDefinition / ExtensionElements	(as named)	Vendor extension mechanism
Import	Import	External type/schema reference
Auditing / Monitoring	Auditing, Monitoring	Process-level audit/monitor placeholders

Out of scope

Element / family	bpmn-moddle types	Reason
Choreography family	Choreography, SubChoreography, CallChoreography, ChoreographyTask, ChoreographyActivity, GlobalChoreographyTask	Separate Choreography Modeling Conformance subclass
Conversation family	Conversation, SubConversation, CallConversation, GlobalConversation, ConversationNode, ConversationLink, ConversationAssociation	Modeling-only, not execution
Collaboration family	Collaboration, Participant, ParticipantAssociation, ParticipantMultiplicity, PartnerEntity, PartnerRole, InteractionNode, MessageFlow, MessageFlowAssociation	Not animated by Clause 13; inter-process messaging is covered by Message events. Note §2.3.2 names the "definitional Collaboration" for import — that is a server/converter concern, not a library one
Category machinery	Category, CategoryValue	Definitions-level taxonomy roots — consumed at load as the resolution input a Group embeds its value from (ADR-039); not carried as model elements
Cross-namespace	Relationship	Not execution-related
DI / DC	BPMNShape, BPMNEdge, Bounds, Point, all bpmndi:* and dc:*, di:*	Visual layout metamodel; not part of execution conformance
BPEL mapping	(no bpmn-moddle types)	Separate conformance subclass

Boundary cases noted

• Lane / LaneSet — in scope, model-only. "Non-operational" governs execution, not representation: §2.3.1 lets a conformant tool ignore lanes at run time (they carry no token semantics — activities in lanes execute exactly as if no lanes existed), but the model must still hold them. Two independent reasons: §2.3.2 obliges an importer to support Process diagrams, and dropping a modeller's lanes is not supporting them; and ADR-024 §2.8 guarantees a semantic round-trip, which export cannot deliver for a structure the model never stored. So: engine MUST parse and preserve, MUST NOT attach behaviour — the rule this document always stated, now with its clause grounding. The model holds them: pkg/model/lanes carries Lane and LaneSet, and a Process holds its lane sets. What remains is the import, which is a converter task rather than a model gap.
• Boundary events on CallActivity — explicitly allowed by §10.5.4. In scope.
• Event Sub-Process — modeled as SubProcess with triggeredByEvent=true. In scope.
• Compensation Association — Association between an activity and its compensation handler. The element is visual elsewhere; here it carries normative semantics.
• Artifacts (§8.4.1) — in scope, model-only (ADR-039). The standard's three — Association (plain shape), TextAnnotation, Group — follow the Lane reading: §2.3.1 lets execution ignore them, and the model carries them for §2.3.2 loading and the converters' semantic round-trip. pkg/model/artifacts holds the three kinds behind a closed Artifact interface; Process and SubProcess carry the collection; no execution path reads one. The compensation shape of Association stays what the row above says — the boundary's handler wiring, never duplicated as an artifact. Category/CategoryValue remain un-carried: load-time resolution input only (the out-of-scope table's row).

Spec section index (for cross-reference)

The chapter-10 rows below once read Activities §10.5, Events §10.4, Data §10.3 — a transposition that contradicted every detail file in this extract, and the boundary-event note above ("explicitly allowed by §10.5.4"). It had propagated into nine wrong § pins in the converter's modeler-facing refusals before it was caught. The order is Activities, Data, Events, Gateways.

Topic	Spec section
Conformance subclasses	§2
Process Execution Conformance (§2.3.1 semantics, §2.3.2 import)	§2.3
Process Modeling Conformance sub-classes (Descriptive / Analytic / Common Executable) — not this engine's target	§2.2.1
Process model	§10
Activities	§10.3
Data (Items and Data)	§10.4
Events	§10.5
Gateways	§10.6
Execution semantics (state machines, token flow)	§13
Correlation	§8.4.2