/elements response for nested behavioral flows appears to omit featureChain information

[jennywang123]

We are testing published SysML v2 behavioral models with OpenMBEE Flexo.

Runtime used:

openmbee/flexo-sysmlv2:v0.1.1
openmbee/flexo-mms-layer1-service:v0.2.2
We also observed the same payload pattern earlier with:

openmbee/flexo-sysmlv2:omg
openmbee/flexo-mms-layer1-service:v0.2.2

Issue:
For a small nested action workflow model, the published API works and returns the expected model elements, but the /elements payload for the behavioral flows appears to be missing featureChain information.

The model includes nested actions and flow statements between nested attributes such as:

orbit.availablePower_W -> science.availablePower_W
science.avgDataRate_Mbps -> this.avgDataRate_Mbps
science.scienceScore -> this.scienceScore

Example model shape

package Simple_Actions {
action def OrbitToFlux {
in attribute panelArea_m2 : Real;
in attribute perihelion_AU : Perihelion_AU;
out attribute availablePower_W : Real;
}

action def PowerToScience {
in attribute availablePower_W : Real;
out attribute avgDataRate_Mbps : Real;
out attribute scienceScore : Real;
out attribute dutyCycle : DutyCycle;
}

action def RunSimpleCampaign {
in attribute panelArea_m2 : Real;
in attribute perihelion_AU : Perihelion_AU;
out attribute avgDataRate_Mbps : Real;
out attribute scienceScore : Real;
out attribute dutyCycle : DutyCycle;

action orbit: OrbitToFlux;
action science: PowerToScience;

flow panelArea_m2 to orbit.panelArea_m2;
flow perihelion_AU to orbit.perihelion_AU;
flow orbit.availablePower_W to science.availablePower_W;
flow science.avgDataRate_Mbps to this.avgDataRate_Mbps;
flow science.scienceScore to this.scienceScore;
flow science.dutyCycle to this.dutyCycle;

}
}

Steps to reproduce

Start a Flexo MMS backend and SysML v2 API service.

Publish or load a small behavioral model with nested actions and nested flow relationships like the example above.
Query:
GET /projects
GET /projects/{projectId}/branches/{branchId}
GET /projects/{projectId}/commits/{commitId}/roots
GET /projects/{projectId}/commits/{commitId}/elements
Inspect the /elements payload for the nested behavioral flow elements.

Observed
/projects works
/branches/{branch} works
/commits/{commit}/roots works
/commits/{commit}/elements works
named action definitions and action usages are present in /elements
declaredName and qualifiedName are present for relevant actions/usages
For example, we do see named elements such as:

RunSimpleCampaign
OrbitToFlux
PowerToScience
orbit
science

However:

the /elements payload contains 0 occurrences of featureChain
So the behavioral flow structures appear to be present only at a higher-level relation shape, without the feature-chain detail needed to identify nested attribute endpoints precisely.

Expected

Either:

featureChain should be present in /elements for nested behavioral flow relationships like these

Or:

the intended payload structure for representing nested action-to-action feature flows should be documented

Questions:
Is featureChain expected to be present in /elements for nested behavioral flows of this form?
If not, what is the intended API representation for those nested flow endpoints?
Could you provide a small known-good /elements example for a nested behavioral flow model?