STPA control-actions embedded in controllers no longer extracted as artifacts

[avrabe]

Summary

Control actions defined inline within controllers: entries in STPA YAML are no longer extracted as standalone control-action artifacts. This is a regression — the same YAML produced 19 control-action artifacts in an earlier rivet version (PR pulseengine/loom#61, merged 2026-03-22) but produces 0 in rivet 0.3.0.

Reproduction

In pulseengine/loom, safety/stpa/control-structure.yaml defines controllers with inline control actions:

controllers:
  - id: CTRL-1
    name: Parser
    type: automated
    control-actions:
      - ca: CA-1
        target: CP-1
        action: Parse operator into Instruction variant
      - ca: CA-2
        target: CTRL-3
        action: Report unsupported instructions in function

Seven controllers define a total of 19 control actions (CA-1 through CA-19).

$ rivet list --type control-action
0 artifacts

Expected: 19 control-action artifacts extracted, with issued-by links to their parent controllers and acts-on links to their targets.

Context

When PR pulseengine/loom#61 was merged, rivet stats reported 185 total artifacts including 19 control-actions. The current count is 144 — exactly 22 missing UCAs (see rivet#129) + 19 missing control-actions = 41 missing.

The control-action artifact type in the STPA schema expects:

• yaml-section: control-actions (top-level section)
• Required fields: action (string)
• Required links: source (issued-by → controller), target (acts-on → controlled-process/controller)

The inline format inside controllers provides all the necessary data (ca = ID, action = description, target = acts-on target) but is not being parsed into standalone artifacts.

Expected Behavior

Either:

1. Extract inline control actions from controller entries as standalone artifacts (as was done previously)
2. Document that control actions must be in a separate control-actions: top-level section
3. Warn when controller entries have control-actions: fields that aren't being extracted

Related

• STPA yaml-sections for UCA type is hardcoded with rivet-specific section names #129 — STPA yaml-sections for UCA type hardcoded with rivet-specific names

Environment

• rivet 0.3.0 (f43c442 feat/parallel-improvements 2026-04-07)
• Project: pulseengine/loom