feat: 6-phase workflow spine + plan-review pipeline (v3.1.0)

skills/writing-plans/SKILL.md

@@ -1,6 +1,7 @@
 ---
 name: writing-plans
 argument-hint: "[task description]"
+user-invocable: true
 description: >
   Use when a multi-step implementation task needs to be broken down before coding begins. Activate for keywords like "plan", "break down", "implementation steps", "task list", "how to implement", "write a plan", or when a feature spans multiple files or components. Also trigger when handing off work to another developer, when the user says "let's plan this out", or when a task is complex enough that jumping straight to code would be risky. If in doubt, plan first.
 ---
@@ -22,6 +23,18 @@ description: >
 
 ---
 
+## Save Location
+
+Write the plan document to:
+
+```
+docs/claudekit/plans/YYYY-MM-DD-<topic>-plan.md
+```
+
+Create the `docs/claudekit/plans/` directory if it does not exist. Use today's date and a short, kebab-case topic slug matching the related design doc (if any).
+
+---
+
 ## Plan Document Format
 
 ### Header Section
@@ -359,5 +372,7 @@ mark user as verified in database.
 ## Related Skills
 
 - `brainstorming` -- Use before writing plans when requirements are unclear or need exploration
+- `autoplan` -- After the plan is written, run autoplan (or individual plan-*-review skills) to pressure-test it on strategy, architecture, design, and DX before implementation
+- `plan-ceo-review`, `plan-eng-review`, `plan-design-review`, `plan-devex-review` -- Individual dimension reviews of a written plan
 - `executing-plans` -- Use after writing a plan to execute it with subagent-driven development and review gates
 - `test-driven-development` -- Plans follow TDD principles; reference this skill for strict red-green-refactor enforcement