fix(skills): plans reference the spec instead of restating it — end to end (SUP-333 A)

Consolidates the reference-discipline change with every consumer of it,
so this PR is independently mergeable (previously split across two
stacked PRs whose intermediate state left the SDD spec reviewer blind).

writing-plans: plans reference the spec — never restate, paraphrase,
or summarize it; spec owns WHAT/WHY, plan owns HOW; cite by path in
the header (**Spec:** template line) and by section where a task needs
context; No Placeholders repetition stays intra-plan; no-spec branch
scoped to conversational-requirements-only (eval-caught: an agent used
an unscoped no-spec branch to skip writing the spec entirely).

brainstorming: spec path loophole closed (claude shortened
docs/superpowers/specs/ to docs/specs/, documented run); an existing
differently-named docs dir is not a "user preference".

subagent-driven-development: Spec Context section — the controller
reads the plan-cited spec and pastes cited sections into implementer
and spec-reviewer prompts; the spec reviewer's diff-only rule gets a
spec-document exception. Without this, reference discipline starves
the pipeline of requirements.

executing-plans: Step 1 reads the spec the plan cites (the
non-subagent path; plans are no longer self-contained).

Eval evidence (quorum, full-stack text): cost-spec-plan-duplication
claude 3/3 pass (RED: 5/5 agents failed), codex pass, pi pass (the
683-line duplication RED agent); sdd-spec-context-consumed functional
pass with deterministic dispatch-prompt check;
writing-plans-no-spec-conversational 2/2 pass;
triggering-writing-plans canary 3/3.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

skills/brainstorming/SKILL.md

@@ -109,8 +109,7 @@ digraph brainstorming {
 **Documentation:**
 
 - Write the validated design (spec) to `docs/superpowers/specs/YYYY-MM-DD-<topic>-design.md`
-  - The `docs/superpowers/` prefix is the convention; do not shorten it to `docs/specs/`
-  - (User preferences for spec location override this default)
+  - (An explicit user instruction overrides this default; an existing differently-named docs directory does not)
 - Use elements-of-style:writing-clearly-and-concisely skill if available
 - Commit the design document to git
 

skills/executing-plans/SKILL.md

@@ -16,7 +16,7 @@ Load plan, review critically, execute all tasks, report when complete.
 ## The Process
 
 ### Step 1: Load and Review Plan
-1. Read plan file
+1. Read plan file, and the spec it cites in its `**Spec:**` header (plans reference requirements rather than restating them)
 2. Review critically - identify any questions or concerns about the plan
 3. If concerns: Raise them with your human partner before starting
 4. If no concerns: Create todos for the plan items and proceed

skills/subagent-driven-development/SKILL.md

@@ -86,6 +86,10 @@ digraph process {
 }
 ```
 
+## Spec Context
+
+If the plan's header cites a spec (`**Spec:** <path>`), read it once during plan extraction. Plans reference requirements rather than restating them — when a task cites a spec section, paste that section's text into the implementer and spec-reviewer prompts along with the task text. Implementer subagents never read the spec file themselves; the spec reviewer may additionally read it at the cited path (its prompt says so).
+
 ## Model Selection
 
 Use the least powerful model that can handle each role to conserve cost and increase speed.

skills/subagent-driven-development/implementer-prompt.md

@@ -12,6 +12,8 @@ Subagent (general-purpose):
 
     [FULL TEXT of task from plan - paste it here, don't make subagent read file]
 
+    [If the task cites spec sections, paste the cited sections' text here too]
+
     ## Context
 
     [Scene-setting: where this fits, dependencies, architectural context]

skills/subagent-driven-development/spec-reviewer-prompt.md

@@ -12,7 +12,7 @@ Subagent (general-purpose):
 
     ## What Was Requested
 
-    [FULL TEXT of task requirements]
+    [FULL TEXT of task requirements, including the text of any spec sections the task cites]
 
     ## What Implementer Claims They Built
 
@@ -28,7 +28,7 @@ Subagent (general-purpose):
     git diff [BASE_SHA]..[HEAD_SHA]
     ```
 
-    Only read files in this diff. Do not crawl the broader codebase.
+    Only read files in this diff. Do not crawl the broader codebase. (One exception: if the requirements cite a spec document, you may read that spec at its cited path.)
 
     ## Read-Only Review
 

skills/writing-plans/SKILL.md

@@ -11,14 +11,14 @@ Write comprehensive implementation plans assuming the engineer has zero context
 
 Assume they are a skilled developer, but know almost nothing about our toolset or problem domain. Assume they don't know good test design very well.
 
-**Plans reference the spec; they never restate it.** The spec owns the WHAT and WHY — requirements, acceptance criteria, design decisions. The plan owns the HOW — tasks, files, code, commands. Cite the spec by path in the header and by section where a task needs context. Re-deriving spec content inline doubles the documents and lets them drift apart. "Zero context" means the engineer can execute each step mechanically; it does not mean the plan repeats what the spec already says — they can read the spec at the cited path.
+**Plans reference the spec; they never restate, paraphrase, or summarize it.** The spec owns the WHAT and WHY — requirements, acceptance criteria, design decisions; the plan owns the HOW — tasks, files, code, commands. Cite it by path in the header and by section where a task needs context. Reference discipline never means skipping the spec: if brainstorming produced one, it exists and the plan cites it. No Placeholders still requires repeating code and commands WITHIN the plan; copying FROM the spec is different: a step that needs a requirement's prose is under-specified — turn it into a concrete action. Snapshotting spec text into the plan hides drift, not prevents it. "Zero context" means each step is mechanically executable, not that the plan repeats the spec.
 
 **Announce at start:** "I'm using the writing-plans skill to create the implementation plan."
 
 **Context:** If working in an isolated worktree, it should have been created via the `superpowers:using-git-worktrees` skill at execution time.
 
 **Save plans to:** `docs/superpowers/plans/YYYY-MM-DD-<feature-name>.md`
-- (User preferences for plan location override this default)
+- (An explicit user instruction overrides this default; an existing differently-named docs directory does not)
 
 ## Scope Check
 
@@ -55,7 +55,7 @@ This structure informs the task decomposition. Each task should produce self-con
 
 **Goal:** [One sentence describing what this builds]
 
-**Spec:** [Path to the spec doc, e.g. `docs/superpowers/specs/YYYY-MM-DD-<topic>-design.md` — requirements and design decisions live there; do not restate them here]
+**Spec:** [Path to the spec doc, e.g. `docs/superpowers/specs/YYYY-MM-DD-<topic>-design.md` — requirements and design decisions live there; do not restate them here. Only if no spec doc exists (requirements arrived conversationally; brainstorming never ran): write "none — requirements:" and state them once here, not per task]
 
 **Architecture:** [2-3 sentences about approach]