Enrich the task template for new cards (task 07)

Merge the highest-value slots from a fuller development-task template
into bench's lean one: an optional Depends on header line, an Affected
areas line in Context, Out of scope bullets in What to build, edge-case
and Given/When/Then guidance in Acceptance, and a Risks slot in Notes.
Each slot says who consumes it and is marked deletable — empty
boilerplate is worse than absence.

The load-bearing contracts are unchanged: exact Status values, the Open
questions heading the NOT READY gate keys off, Acceptance as the review
target, and the template staying off the board. Organisation process
(staging, sign-offs, approvals, contacts) is deliberately absent; a new
contract test pins both the gained slots and what must not grow back.
CLAUDE.md's Task file format section documents the Depends on line.

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

CLAUDE.md

@@ -413,5 +413,15 @@ Type is orthogonal to status. A discovery task — research, scoping, spiking an
 approach — moves through the same five stages as everything else; "discovery"
 describes the work, not where it sits on the board.
 
+An optional **Depends on** line can name what must land first — task numbers
+or external preconditions — so sequencing lives in the header instead of
+prose asides:
+
+```markdown
+**Depends on:** 03, 05
+```
+
+The board does not enforce it; it informs whoever picks the next card.
+
 The rest of the file is freeform — description, research findings, approach,
 open questions, whatever is relevant to the current stage.

tasks/task-template.md

@@ -3,6 +3,15 @@ Copy this file into backlog/ as NN-short-kebab-title.md — numbers are
 allocated in creation order and stay with the task for life. The board never
 lists this template (it only reads the stage directories). The **PR:** line
 is added by the board itself when the task reaches review/ with a branch.
+
+Anything below marked *optional* is deletable, and deleting beats leaving
+it hollow — an empty boilerplate section reads as thinking that never
+happened. Board process (review, PR, CI, merge) and the project-wide
+definition of done stay off the card: the board does the former
+mechanically and the repo CLAUDE.md owns the latter.
+
+This template lives in tasks/, which updates never touch — improvements to
+it ship only with fresh installs, so local edits are yours to keep.
 -->
 
 # NN — Imperative title: what changes when this is done
@@ -10,6 +19,8 @@ is added by the board itself when the task reaches review/ with a branch.
 **Status:** Backlog
 **Priority:** Medium — one clause on why it sits at this level
 **Type:** Feature
+**Depends on:** 03, 05 — task numbers or external preconditions that must
+land first, for whoever sequences the board; delete when nothing blocks this
 
 One paragraph for someone — human or agent — who has the codebase but not
 the conversation: what this task changes, and why it is worth doing.
@@ -18,7 +29,12 @@ the conversation: what this task changes, and why it is worth doing.
 
 What exists today and why it falls short. Point at real places rather than
 describing from memory: packages and modules (`packages/domain/...`), prior
-tasks (`../done/...`), reference documents (`../../reference/...`).
+tasks (`../done/...`), plan files (`../../plans/...`) and reference
+documents (`../../reference/...`) — a link outlives a summary.
+
+**Affected areas:** the modules or layers this touches, one line in the
+repo CLAUDE.md's module-map vocabulary — telling reviewers where to look
+and agents where to stop. Optional: delete when the title already says it.
 
 ## What to build
 
@@ -29,13 +45,24 @@ convenience.
 - First piece
 - Second piece
 
+**Out of scope** — the adjacent changes this task deliberately does not
+make. This is what bounds the work agent's brief; scope creep is the
+classic headless failure. Optional, but cheap insurance on any task with
+tempting neighbours — delete rather than leave empty.
+
+- Not this, even though it is nearby
+
 ## Acceptance
 
-Observable outcomes, not implementation steps. The repo's definition of done
-(tests pass, `lint-imports` clean, new behaviour covered) applies on top.
+Observable outcomes, not implementation steps — review agents judge the
+diff against exactly this list. The repo's definition of done (tests pass,
+`lint-imports` clean, new behaviour covered) applies on top; don't restate
+it. Given/When/Then phrasing is welcome where it sharpens a criterion, and
+edge cases belong here too — boundaries, empty inputs, failure paths.
 
 - [ ] Something a reviewer can check without reading the diff
-- [ ] Another one
+- [ ] Given <a state>, when <the action>, then <the observable result>
+- [ ] Edge case: the boundary that would embarrass this feature if missed
 
 ## Open questions
 
@@ -51,3 +78,10 @@ it) when the task is ready to action.
 Freeform: research findings, links, decisions taken along the way. The
 board's relevance checks and PR reviews append their reports below this
 line as the task moves.
+
+**Risks** — known hazards and blockers: what could sink the approach, what
+the change might break, what must hold for it to work. For the author
+weighing the task and the reviewer double-checking it. Optional: delete
+when there is nothing real to name.
+
+- None worth naming yet.

tests/test_task_template.py

@@ -0,0 +1,85 @@
+"""The task template's load-bearing contract. Its headings are machinery,
+not prose convention: the body becomes the work agent's brief verbatim,
+Acceptance is what review agents judge against, and the Open questions
+heading is what the NOT READY gate keys off — so the template must keep
+them, exactly, in order. Task 07 enriched the template; these tests pin
+both what it gained and what it must never grow.
+
+    python3 -m unittest discover -s tests -v
+"""
+
+from __future__ import annotations
+
+import re
+import unittest
+from pathlib import Path
+
+TEMPLATE = (Path(__file__).resolve().parents[1]
+            / "tasks" / "task-template.md")
+
+LOAD_BEARING_HEADINGS = [
+    "Context", "What to build", "Acceptance", "Open questions", "Notes",
+]
+
+# Organisation process the board either does mechanically or doesn't own —
+# deliberately absent from the template, and it must not grow back.
+ORG_PROCESS_TERMS = (
+    "staging", "sign-off", "signoff", "qa ", "product owner",
+    "browser", "device matrix", "contact",
+)
+
+# The slots task 07 added, each of which earns its keep on the card.
+ENRICHED_SLOTS = (
+    "**Depends on:**",
+    "**Affected areas:**",
+    "**Out of scope**",
+    "**Risks**",
+    "Given <",
+    "Edge case",
+)
+
+
+class TemplateContract(unittest.TestCase):
+    def setUp(self):
+        self.text = TEMPLATE.read_text()
+
+    def test_load_bearing_headings_survive_in_order(self):
+        headings = re.findall(r"^## (.+)$", self.text, re.MULTILINE)
+        self.assertEqual(headings, LOAD_BEARING_HEADINGS)
+
+    def test_status_is_an_exact_board_value(self):
+        self.assertIn("**Status:** Backlog\n", self.text)
+
+    def test_open_questions_section_names_the_gate(self):
+        section = self.text.split("## Open questions", 1)[1]
+        section = section.split("## ", 1)[0]
+        self.assertIn("`NOT READY`", section)
+
+    def test_enriched_slots_are_present(self):
+        for slot in ENRICHED_SLOTS:
+            with self.subTest(slot=slot):
+                self.assertIn(slot, self.text)
+
+    def test_new_slots_say_they_are_deletable(self):
+        # "delete" appears with each optional slot, so authors trim rather
+        # than leave hollow sections behind.
+        for slot in ("**Depends on:**", "**Affected areas:**",
+                     "**Out of scope**", "**Risks**"):
+            with self.subTest(slot=slot):
+                paragraph = self.text.split(slot, 1)[1].split("\n\n", 1)[0]
+                self.assertIn("delete", paragraph.lower())
+
+    def test_no_organisation_process_creeps_in(self):
+        lowered = self.text.lower()
+        for term in ORG_PROCESS_TERMS:
+            with self.subTest(term=term):
+                self.assertNotIn(term, lowered)
+
+    def test_template_sits_outside_every_stage_directory(self):
+        # The board lists stage directories only; the template must stay a
+        # sibling of them, not a card.
+        self.assertEqual(TEMPLATE.parent.name, "tasks")
+
+
+if __name__ == "__main__":
+    unittest.main()