Workshop

Execute ALL steps in order. Do not skip or deviate.

Entry

1. Preconditions above must pass. Do not re-run Discover / live CLI / Terraform parse.

2. Stale Generate/decide guard (mandatory, single authoritative point — runs before any other Entry step or Loop branch). This condition covers EVERY re-entry path into workshop (Apply & reprice, Compare scenarios, or exiting workshop without ever entering workshop-refresh.md) — do not rely on a narrower guard inside workshop-refresh.md alone; by the time that file’s own “Stale Generate guard” step runs, this step has already reset phases.generate, so a second == "completed" check there can never fire again.

   Fires when ANY of: phases.generate (or later) is "completed"; phases.generate is "in_progress" (an interrupted Generate); current_phase == "generate" with run_mode set (choice C was taken — phases.generate may still be "pending" here if Generate was never actually entered, which is why this condition is written on current_phase, not phases.generate); current_phase == "complete" with run_mode set (a resolved decide/decide_and_execute state). Step 3 below normalizes current_phase/run_mode for every one of these four conditions, not only the last.

   On fire: apply Estimate _re_entry_guard confirm → set every phase downstream of Estimate back to "pending" in .phase-status.json (reset_downstream_to_pending).

   Do NOT delete anything Generate wrote. An earlier version of this guard deleted a named subset of Generate’s output files (baseline.tf, variables.tf, etc.) on the theory that only those exact filenames are “purely generated.” That is false: generate-terraform.md tells users to fill in terraform.tfvars, and per its Step 11 header/opt-out instructions users are told to hand-edit baseline.tf (replace placeholder contact emails) and variables.tf (comment out blocks to decline the security baseline) — both keep their generated filename after being customer-edited. _contributes: frontmatter identifies each fragment’s ORIGINAL output path, not whether that path’s CURRENT contents are still disposable; there is no reliable way to tell “still exactly as generated” apart from “customer-edited since” from the filename alone, so no filename-based deletion list can be made safe. terraform/ and every other Generate-produced path (generation-*.json, MIGRATION_GUIDE.md, README.md, migration-report.html, report-validation-status.json) are left completely untouched by this guard — Design/Estimate get overwritten by the reprice, but the previous execution pack these files represent is never modified, deleted, or archived by workshop re-entry.

   Reaching the Decision gate afterward with a stale execution pack still on disk is fine: validate-heroku-migration-report.py --mode decision determines “pre-execution” from .phase-status.json‘s own phases.generate value (reset to "pending" by this guard above), not from whether terraform//generation-*.json happen to exist on disk — see that validator’s decision-mode check. A prior cycle’s execution pack legitimately coexisting with a fresh decision is the expected, supported state; it is what lets the user compare the new decision against files they may still be relying on, and it is exactly what the next accepted Generate run will overwrite in its own course.

   If the user does NOT confirm the guard (declines the re-entry), stop here — do not patch preferences or re-run Design/Estimate; the existing execution pack and decide/execute state are left untouched either way.

3. Normalize current_phase/run_mode on ANY accepted re-entry (mandatory). This step runs whenever step 2 fired and the user confirmed — it is the same re-entry event, not a separately-triggered one. An earlier version of this step only fired when current_phase == "complete", which covers the terminal decide-complete resume (run_mode: "decide", phases.generate: "pending") but NOT the three current_phase: "generate" states step 2 also detects as stale (choice C taken, with phases.generate "pending", "in_progress", or "completed"). Scoping the reset to one named current_phase value while the guard above fires on four different conditions left three of those four states with a normalized phases.generate but a STALE current_phase/run_mode — a session resumed after workshop exit would then select Generate again (per SKILL.md § “Gate-presented resume”, which requires run_mode absent to detect an unresolved gate) instead of reaching the still-unresolved Decision gate.

   Whenever step 2’s guard fired and was confirmed, ALSO reset current_phase to "estimate" and clear run_mode (read-merge-write, remove the key rather than setting it to null) before step 4 — for every one of step 2’s four trigger conditions, not only the current_phase == "complete" case. This returns the run to the pre-gate state the workshop expects in every accepted-re-entry state, not just the terminal one.

4. Set phases.workshop to "in_progress" (do not change current_phase further — sidebars never own it). Prefer leaving current_phase at estimate until the user exits workshop back to the Decision gate (see estimate-assemble.md § “Post-Estimate: Decision Gate” and workshop-assemble.md).

Loop

1. If scenarios/index.json missing → workshop-refresh.md § Baseline capture.
2. workshop-sheet.md — present knobs + actions.
3. Branch:
   • Apply & reprice → workshop-refresh.md (inner Design/Estimate) → workshop-compare.md
   • Compare scenarios → workshop-compare.md
   • Exit workshop → workshop-assemble.md (resolve sidebar) → returns to the Decision gate in estimate-assemble.md (never directly to Generate — see workshop-assemble.md)
   • Exit to full Clarify → danger; Clarify re-entry only on explicit confirm

Hard rules

These rules restate the canonical contract in references/vendored/workshop/workshop-invariants.md (vendored from skills/shared/workshop/workshop-invariants.md, kept byte-identical by shared:sync). When this table and that file disagree, the invariants file wins — fix this table.

Decline without entering

When Estimate offer [B] Proceed to the decision is chosen, do not enter this phase’s fragments — mark phases.workshop "completed" (resolved/ declined) per sidebar semantics in INTERPRETER.md, then present the Decision gate (estimate-assemble.md § “Post-Estimate: Decision Gate”). current_phase stays "estimate" — the gate, not this decline path, sets the next state from the user’s A/C choice.