Stage	Directory	Contents
Source input	`teacher/inbox/`	Original target STEP/STP files.
Extracted evidence	`teacher/evidence/`	Private geometry facts extracted from each source.
Agent A input	`reconstruction/inbox/`	Sanitized evidence packets and reconstruction requests.
Agent A result	`reconstruction/designir/`	Executable `*.designir.json` models.
Independent rebuild	`reconstruction/output/`	STEP rebuilt without teacher-file access; SimpleCAD jobs may also emit model JSON.
Agent B input	`acceptance/inbox/`	Acceptance manifests linking teacher, DesignIR, rebuild, and edit contract.
Acceptance result	`acceptance/reports/`	Geometry, topology, semantic, and parameter-perturbation reports.
Failed/unsupported	`quarantine/`	Unsupported vocabulary, invalid cases, and failure clusters.
Experience candidates	`promotion/candidates/`	Generalized methods proposed from validated cases.
Replay gate	`promotion/replay_validated/`	Methods repeated successfully across independent cases.
Final distilled result	`promotion/promoted/library.json`	Only deterministic, promoted experience consumed by CAD Router.

Data flow

teacher/inbox/*.step
  -> teacher/evidence/
  -> reconstruction/inbox/
  -> reconstruction/designir/
  -> reconstruction/output/*.step
  -> acceptance/inbox/
  -> acceptance/reports/
  -> promotion/candidates/
  -> promotion/replay_validated/
  -> promotion/promoted/library.json

Agent A cannot read teacher/inbox/. Agent B may read the teacher STEP and the rebuilt result, but neither agent can directly publish experience. Promotion is performed only by the deterministic policy gate.

The .gitkeep files preserve this layout in Git. Runtime STEP files, evidence, rebuilds, and reports remain local by default.