Corrective Action

Corrective Action (manufacturing-quality/as9100/corrective-action)

Use when the task is closing a corrective action record for a manufacturing nonconformance: containment, five-whys root cause analysis, corrective action, and effectiveness evidence must all be in place before the record closes per AS9100 practice.

Domain quick reference

• The closure state machine walks four stages in order: containment, root-cause, corrective-action, effectiveness.
• Containment is the immediate action that isolates the effect of a nonconformance; a placeholder answer (none, n/a, unknown) does not count as a recorded containment.
• The five-whys root cause chain needs at least 3 recorded levels, each non-empty and distinct from the previous answer; a repeated adjacent answer is circular and fails the chain.
• Corrective action removes the root cause; preventive action prevents recurrence. A blank or placeholder corrective action cannot close the record.
• Effectiveness evidence must describe an observed result and must not restate the root cause text, which would be circular evidence.
• record_status returns one of: containment-missing, root-cause-incomplete, corrective-action-missing, effectiveness-pending, closed. closure_verdict adds the missing items for the current stage.
• AS9100 frames corrective action as the required response that closes a nonconformance; the stage machine here is a practical summary, not clause text.

Workflow

1. Record the problem statement as the record problem.
2. Record the containment action and check it with containment_ok (no placeholders).
3. Build the five-whys chain and validate it with root_cause_chain_ok (depth, empty answers, circularity).
4. Record the corrective action and the preventive action; check the corrective action with corrective_action_ok.
5. Record effectiveness evidence and check it with effectiveness_evidence_ok against the root cause statement.
6. Call record_status for the stage and closure_verdict for the missing items; close only at status closed.

Pitfalls

• Placeholder answers: none, n/a, na, no, unknown, and not-applicable fail containment_ok, corrective_action_ok, and the whys chain.
• Circular why chains: the same answer twice in a row means the analysis stopped; the chain needs a new level each time.
• Circular effectiveness evidence: evidence that repeats the root cause statement proves nothing and keeps the record pending.
• Closing without effectiveness: a record with containment, whys, and corrective action but no evidence stays effectiveness-pending.
• Containment versus corrective action: containment isolates the effect, corrective action removes the cause; one does not replace the other.
• Missing keys: record_status raises ValueError when problem, containment, whys, or corrective_action is absent.

Behavior contract (gate 3)

The closure stage logic is exercised by the gate 3 contract test: scripts/test_corrective_action.py against scripts/corrective_action_logic.py (stdlib unittest, offline). Run: python3 scripts/test_corrective_action.py

Compliance

• Standards referenced, not reproduced: AS9100 corrective action is summarized as a stage machine and workflow, common aerospace problem-solving practice per standards-map.yaml.
• compliance: STANDARDS-REF, gated: false.