feat(gcp-to-aws): post-Estimate Decision gate — Generate becomes opt-in

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/phases/estimate/estimate.md

@@ -138,32 +138,44 @@ estimate artifact(s), present a brief summary, then **return to the workshop
 loop**. Do **not** emit `HANDOFF_OK`, do **not** update `.phase-status.json`, do
 **not** offer the what-if workshop below.
 
-### Outer Estimate — deferred Generate advance
+### Outer Estimate — Decision gate
 
 After outer-run `HANDOFF_OK`, use the Phase Status Update Protocol
 (read-merge-write) — **in the same turn** as the summary:
 
 1. Set `phases.estimate` to `"completed"`
 2. Ensure `phases.workshop` exists (seed `"pending"` if missing)
-3. **Do not** set `current_phase` to `"generate"` yet — leave `current_phase` at
-   `"estimate"` until the workshop sidebar is resolved (entered then exited,
-   or declined)
-4. Offer the what-if workshop below (infra route only)
+3. **Do not** set `current_phase` to `"generate"` — Generate is opt-in from
+   here on. Leave `current_phase` at `"estimate"` and present the Decision
+   gate below.
 
-### Post-Estimate: What-If Workshop Offer
+### Post-Estimate: Decision Gate
 
-When `gcp-resource-inventory.json` + `aws-design.json` + `estimation-infra.json`
-exist, offer:
+**The decision is the product; execution artifacts are opt-in.** The verdict
+(`recommendation.outcome` / `path`) already exists in the estimate artifacts —
+present it and let the user choose what happens next. Never advance to
+Generate without an explicit choice of option C (or an explicit later request
+for Terraform/scripts).
+
+Present (values from the active estimate artifacts; one line each):
 
 ```
-Estimate complete. Before Generate, want to see how the numbers move if you
-change something? I can reprice scenarios side by side in about a minute each,
-without re-running discovery — for example: a different AWS region, cheaper
-single-AZ database for staging, Kubernetes (EKS) instead of Fargate, or
-ARM-based (Graviton) compute.
-
-[A] Enter what-if workshop
-[B] Proceed toward Generate
+Estimate complete.
+
+### Decision pack ready
+
+- Verdict: [outcome_label when recommendation.outcome exists; else path_label]
+- AWS estimate (Balanced): $[X]/mo · Your GCP baseline: [figure with its
+  baseline-quality label from estimate-infra.md Part 1 — apply the
+  not-comparable rule when the sources measure different things]
+- Timeline if you execute: ~[N–M] weeks ([complexity tier], from
+  shared/migration-complexity.md — omit this line when no tier signal exists)
+- Deferred to specialists: [BigQuery / other deferred rows, or omit line]
+
+[A] Done for now — I have what I need to decide
+[B] Explore what-ifs — reprice scenarios side by side (~1 min each): region,
+    single-AZ database, EKS vs Fargate, Graviton
+[C] Generate Terraform and migration scripts
 ```
 
 **Data-justified scenario hint (add one line when applicable):** if a material
@@ -172,13 +184,27 @@ assumption was defaulted rather than confirmed — most commonly `availability`
 comparing a [alternative] scenario would bound that assumption before you
 commit." Suggest at most one.
 
-- **A** → Load `references/phases/workshop/workshop.md`. Keep
-  `current_phase: estimate`; set `phases.workshop` → `"in_progress"`.
-- **B** → Mark `phases.workshop` → `"completed"`. Set `current_phase` →
-  `"generate"`. Continue with Feedback/Generate sidebars in `SKILL.md`.
-
-For AI-only / billing-only runs (no infra inventory), skip the workshop offer and
-set `phases.workshop` → `"completed"`, `current_phase` → `"generate"`.
+**Choice handling:**
+
+- **A** → Mark `phases.workshop` → `"completed"` (declined). Set
+  `run_mode: "decide"` and `current_phase: "complete"` in `.phase-status.json`
+  (`phases.generate` **stays** `"pending"` — this combination means "decision
+  complete, execution available on request"; see `schema-phase-status.md`).
+  Then run the post-gate feedback checkpoint per `SKILL.md`. Close with:
+  "Your decision pack is complete. If you decide to migrate, say 'generate the
+  Terraform and migration scripts' — everything is saved and I'll pick up from
+  here."
+- **B** → Load `references/phases/workshop/workshop.md`. Keep
+  `current_phase: estimate`; set `phases.workshop` → `"in_progress"`. On
+  workshop exit, **return to this gate** (options A and C; the workshop's
+  active scenario carries into either) — do not advance to Generate directly.
+- **C** → Mark `phases.workshop` → `"completed"` (declined). Set
+  `run_mode: "decide_and_execute"` and `current_phase` → `"generate"`. Then
+  run the post-gate feedback checkpoint per `SKILL.md` and continue to
+  Generate.
+
+For AI-only / billing-only runs (no infra inventory), present the gate without
+option B and set `phases.workshop` → `"completed"`.
 
 ## Reference Files
 
@@ -193,7 +219,7 @@ set `phases.workshop` → `"completed"`, `current_phase` → `"generate"`.
 FORBIDDEN — Do NOT include ANY of:
 
 - Changes to architecture mappings from the Design phase
-- Execution timelines or migration schedules
+- Execution timelines or migration schedules — **exception:** the Decision gate's one-line timeline band (`~N–M weeks`, tier from `shared/migration-complexity.md`) is allowed; full schedules, week-by-week plans, and runbooks remain Generate-only
 - Terraform or IaC code generation
 - Detailed migration procedures or runbooks
 - Team staffing or resource allocation

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/phases/generate/generate.md

@@ -1,5 +1,13 @@
 # Phase 5: Generate Migration Artifacts (Orchestrator)
 
+> **CONSENT GUARD (check before Step 1):** This phase runs only by explicit
+> opt-in. If `.phase-status.json` → `run_mode` is not `"decide_and_execute"`:
+> when this turn's user message is an explicit Execute request ("generate the
+> Terraform", "create the migration scripts", gate choice C), set
+> `run_mode: "decide_and_execute"` (read-merge-write) and proceed; otherwise
+> STOP — do not generate anything — and re-present the Decision gate (or the
+> decide-complete resume offer) from `estimate.md` / `SKILL.md`.
+
 **Execute ALL steps in order. Do not skip or optimize.**
 
 ## Overview

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/phases/workshop/workshop-assemble.md

@@ -3,23 +3,31 @@
 > Marks the workshop sidebar resolved and returns control to the backbone.
 > Does **not** set `current_phase` to `workshop`.
 
-## When exiting to Generate
+## When exiting the workshop
+
+Workshop exit returns to the **Decision gate** in `estimate.md` — never
+directly to Generate. The user chooses A (done for now) or C (generate) there;
+the active scenario carries into either choice.
 
 1. Set `preferences.workshop.active` to `false` (keep `active_scenario_id`).
 2. Ensure `scenarios/index.json` exists (baseline-only is enough).
 3. Update `.phase-status.json` (read-merge-write):
    - `phases.workshop` → `"completed"`
-   - `current_phase` → `"generate"`
+   - `current_phase` **stays** `"estimate"` (the Decision gate sets the next
+     state based on the user's choice)
    - `last_updated` → now
 4. Emit:
 
    ```
-   HANDOFF_OK | phase=workshop | artifacts=scenarios/index.json | return_to=generate
+   HANDOFF_OK | phase=workshop | artifacts=scenarios/index.json | return_to=decision_gate
    ```
 
-5. Output: "Workshop paused. Active scenario: `{id}`. Proceeding toward Generate."
+5. Output: "Workshop done. Active scenario: `{id}`." Then re-present the
+   Decision gate from `estimate.md` (options A and C — the workshop was just
+   explored, so omit B), with the gate's verdict/cost lines refreshed from the
+   **active scenario's** estimate.
 
 ## Soft postcondition
 
 If scenarios are missing after an empty entry, warn and still mark workshop
-`"completed"` + advance to generate — do not block Generate.
+`"completed"` + return to the Decision gate — do not block the gate.

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/phases/workshop/workshop-sheet.md

@@ -55,7 +55,7 @@ Actions (exactly one):
 
 - **[A] Apply & reprice**
 - **[B] Compare scenarios**
-- **[C] Exit to Generate**
+- **[C] Done — back to the decision gate** (choose "done for now" or "generate scripts" there)
 - **[D] Exit to full Clarify** (danger — confirm first)
 
 ## Step 3: Validate (Apply only)

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/phases/workshop/workshop.md

@@ -33,7 +33,7 @@
 3. Branch:
    - **Apply & reprice** → `workshop-refresh.md` → `workshop-compare.md`
    - **Compare scenarios** → `workshop-compare.md`
-   - **Exit to Generate** → `workshop-assemble.md` → return
+   - **Done / exit** → `workshop-assemble.md` → returns to the Decision gate in `estimate.md`
    - **Exit to full Clarify** → danger; Clarify re-entry only on explicit confirm
 
 ## Hard rules
@@ -55,6 +55,7 @@ file wins — fix this table.
 
 ## Decline without entering
 
-When Estimate offer **[B] Proceed toward Generate** is chosen, mark
-`phases.workshop` `"completed"` (resolved/declined), set `current_phase` to
-`"generate"`, then continue Feedback/Generate sidebars in `SKILL.md`.
+When the user chooses Decision-gate option **A** (done for now) or **C**
+(generate) without entering the workshop, mark `phases.workshop` `"completed"`
+(resolved/declined); the gate's choice handling in `estimate.md` sets
+`run_mode` and `current_phase`.

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/shared/handoff-gates.md

@@ -52,6 +52,10 @@ Patching artifacts to satisfy a gate defeats fail-closed validation and produces
 
 ---
 
+## Decide-complete is terminal, not a failure
+
+`current_phase: "complete"` + `run_mode: "decide"` + `phases.generate: "pending"` is a **valid terminal state** (the user stopped at the decision — see `schema-phase-status.md`). It is Estimate's `HANDOFF_OK` outcome, not a `GATE_FAIL`, not an inconsistent ordering, and not an incomplete run to repair. Do not "fix" it by advancing to Generate; the only valid transition out is the decide-complete resume offer (SKILL.md state machine).
+
 ## Phase re-entry (idempotent runs)
 
 | Situation                                            | Rule                                                                                                                                                                  |

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/shared/schema-phase-status.md

@@ -26,10 +26,21 @@ Lightweight phase tracking. This is the SINGLE source of truth for the `.phase-s
 | `last_updated`  | ISO 8601 | After each phase update                                          |
 | `phases.<name>` | string   | Phase transitions: `"pending"` → `"in_progress"` → `"completed"` |
 
+**Optional field — `run_mode`:**
+
+| Value                  | Meaning                                                                         | Set by                                                      |
+| ---------------------- | ------------------------------------------------------------------------------- | ----------------------------------------------------------- |
+| `"decide"`             | User stopped at the decision — Generate available on request, never auto-loaded | Decision gate choice A (`estimate.md`)                      |
+| `"decide_and_execute"` | User opted into execution artifacts — Generate may load                         | Decision gate choice C, or the decide-complete resume offer |
+| _(absent)_             | Gate not yet reached — no Generate consent exists                               | —                                                           |
+
+**Decide-complete state:** `current_phase: "complete"` + `run_mode: "decide"` + `phases.generate: "pending"` means the decision pack is done and execution was not requested. This is a **terminal-unless-asked** state, not a failure and not an incomplete run: resume offers Generate but never auto-runs it, and never re-runs Estimate. No `"skipped"` status exists — `generate` simply stays `"pending"`.
+
 **Rules:**
 
 - Phase status progresses: `"pending"` → `"in_progress"` → `"completed"`. Never goes backward.
 - Valid phase names: discover, clarify, design, estimate, workshop, generate, feedback.
 - `workshop` is an optional **sidebar** (like feedback): never appears as
   `current_phase`; `"completed"` means resolved (entered or declined).
 - `migration_id` matches the `$MIGRATION_DIR` folder name (e.g., `0226-1430`).
+- `run_mode` is optional; when present it must be `"decide"` or `"decide_and_execute"`. It is flow state (Generate consent), not a design constraint — it never appears in `preferences.json`.

advisor/plugins/aws-startup-advisor/skills/gcp-to-aws/references/vendored/workshop/workshop-invariants.md

@@ -28,9 +28,11 @@
 - The workshop is a sidebar: it NEVER becomes `current_phase`. Entry sets
   `phases.workshop: "in_progress"`; `current_phase` stays at `"estimate"`
   until exit/decline.
-- Exit to Generate (assembler): `phases.workshop: "completed"`,
-  `current_phase: "generate"`. Decline at the Estimate offer: same, without
-  requiring `scenarios/`.
+- Exit (assembler): `phases.workshop: "completed"`. Skills WITHOUT a
+  post-Estimate decision gate advance `current_phase` to `"generate"`. Skills
+  that DEFINE a decision gate re-present that gate — **never** auto-advance to
+  Generate (the gate sets the next state from the user's choice). Decline at
+  the offer: same, without requiring `scenarios/`.
 - Warm-start rule: `current_phase == "estimate"` AND
   `phases.estimate == "completed"` AND `phases.workshop == "pending"` →
   present the workshop offer; NEVER recompute Estimate.

advisor/plugins/aws-startup-advisor/skills/heroku-to-aws/references/vendored/workshop/workshop-invariants.md

@@ -28,9 +28,11 @@
 - The workshop is a sidebar: it NEVER becomes `current_phase`. Entry sets
   `phases.workshop: "in_progress"`; `current_phase` stays at `"estimate"`
   until exit/decline.
-- Exit to Generate (assembler): `phases.workshop: "completed"`,
-  `current_phase: "generate"`. Decline at the Estimate offer: same, without
-  requiring `scenarios/`.
+- Exit (assembler): `phases.workshop: "completed"`. Skills WITHOUT a
+  post-Estimate decision gate advance `current_phase` to `"generate"`. Skills
+  that DEFINE a decision gate re-present that gate — **never** auto-advance to
+  Generate (the gate sets the next state from the user's choice). Decline at
+  the offer: same, without requiring `scenarios/`.
 - Warm-start rule: `current_phase == "estimate"` AND
   `phases.estimate == "completed"` AND `phases.workshop == "pending"` →
   present the workshop offer; NEVER recompute Estimate.

advisor/plugins/aws-startup-advisor/skills/shared/workshop/workshop-invariants.md

@@ -28,9 +28,11 @@
 - The workshop is a sidebar: it NEVER becomes `current_phase`. Entry sets
   `phases.workshop: "in_progress"`; `current_phase` stays at `"estimate"`
   until exit/decline.
-- Exit to Generate (assembler): `phases.workshop: "completed"`,
-  `current_phase: "generate"`. Decline at the Estimate offer: same, without
-  requiring `scenarios/`.
+- Exit (assembler): `phases.workshop: "completed"`. Skills WITHOUT a
+  post-Estimate decision gate advance `current_phase` to `"generate"`. Skills
+  that DEFINE a decision gate re-present that gate — **never** auto-advance to
+  Generate (the gate sets the next state from the user's choice). Decline at
+  the offer: same, without requiring `scenarios/`.
 - Warm-start rule: `current_phase == "estimate"` AND
   `phases.estimate == "completed"` AND `phases.workshop == "pending"` →
   present the workshop offer; NEVER recompute Estimate.