feat(skills): Scope B A2 — 4 竞品生成器注册表+上下文分派+端点接线

注册表 TOOLBOX +4 entry（continue/expand/de-ai/teardown，全 preview-only writes=[]）；
ContextStrategy +with_prior_chapter/text_input；ToolGenerateRequest +text 字段。
toolbox_context 分派新策略（续写→build_continuation_context、原文→build_text_input_context）；
路由续写经 chapter_repo 读最新 accepted/draft 正文注入 builder（core 不 import apps/api，仿 accept_op）。
预览仅 commit ledger 不写业务表（#3）；只声明 tier（#2）；system_prompt 进缓存前缀（#9）。
单测：4 生成器 generate 预览 + 续写读前文/草稿路由 + 扩写/降AI text 路由 + 拆书结构化；
更新 registry/strategy 计数测试（15 工具 / 6 策略）。门禁绿：ruff/format/mypy 196 files/pytest 168(api)+32(skills)。

apps/api/tests/test_toolbox_endpoints.py

@@ -19,9 +19,18 @@ from cryptography.fernet import Fernet
 from fakes_projects import FakeProjectRepo, FakeSession
 from test_projects import _empty_memory_repos
 from ww_agents import Conflict, ContinuityReview
-from ww_agents.schemas import Idea, IdeaListResult
+from ww_agents.schemas import (
+    BookTeardownResult,
+    ContinuationResult,
+    DeAiResult,
+    Idea,
+    IdeaListResult,
+    PolishResult,
+)
+from ww_core.domain.chapter_repo import ChapterDraftView, ChapterView
 from ww_core.domain.outline_write_repo import OutlineWriteView
 from ww_core.domain.project_repo import ProjectCreate
+from ww_core.domain.repositories import OutlineView
 from ww_core.domain.world_entity_repo import WorldEntityWriteView
 from ww_llm_gateway.types import LlmRequest, LlmResponse, ServedBy, Usage
 from ww_shared import AppError, ErrorCode
@@ -85,6 +94,88 @@ class _FakeOutlineWriteRepo:
         )
 
 
+class _FakeOutlineReadRepo:
+    """续写/按章工具读节拍用的内存替身：缺章 → None（端点降级到空节拍）。"""
+
+    def __init__(self, beats_by_chapter: dict[int, list[str]] | None = None) -> None:
+        self._beats = beats_by_chapter or {}
+
+    async def get(self, project_id: uuid.UUID, chapter_no: int) -> Any:
+        beats = self._beats.get(chapter_no)
+        if beats is None:
+            return None
+        return OutlineView(
+            chapter_no=chapter_no, volume=1, beats={"beats": beats}, foreshadow_windows=[]
+        )
+
+    async def list_for_project(self, project_id: uuid.UUID) -> list[Any]:
+        return []
+
+
+class _FakeChapterRepo:
+    """续写读前文用的内存章节替身：按 chapter_no 存 accepted/draft 正文。"""
+
+    def __init__(
+        self,
+        *,
+        accepted: dict[int, str] | None = None,
+        drafts: dict[int, str] | None = None,
+    ) -> None:
+        self._accepted = accepted or {}
+        self._drafts = drafts or {}
+
+    async def latest_accepted(self, project_id: uuid.UUID, chapter_no: int) -> ChapterView | None:
+        content = self._accepted.get(chapter_no)
+        if content is None:
+            return None
+        return ChapterView(
+            project_id=project_id,
+            chapter_no=chapter_no,
+            volume=1,
+            content=content,
+            status="accepted",
+            version=1,
+        )
+
+    async def get_draft(self, project_id: uuid.UUID, chapter_no: int) -> ChapterDraftView | None:
+        content = self._drafts.get(chapter_no)
+        if content is None:
+            return None
+        return ChapterDraftView(
+            project_id=project_id,
+            chapter_no=chapter_no,
+            volume=1,
+            content=content,
+            status="draft",
+            version=1,
+        )
+
+
+class _CaptureGateway:
+    """记录最近一次 req.input（验证续写读前文/原文路由进了 context），返指定 parsed。"""
+
+    def __init__(self, parsed: Any) -> None:
+        self._parsed = parsed
+        self.last_input: str | None = None
+
+    async def run(self, req: LlmRequest) -> LlmResponse:
+        # 工具箱端点恒传序列化文本 context（str）；存为 str 供断言。
+        self.last_input = req.input if isinstance(req.input, str) else str(req.input)
+        return LlmResponse(
+            text=self._parsed.model_dump_json(),
+            parsed=self._parsed,
+            usage=Usage(
+                provider="fake",
+                model="fake",
+                input_tokens=1,
+                output_tokens=1,
+                cost_minor=0,
+                currency="USD",
+            ),
+            served_by=ServedBy(provider="fake", model="fake"),
+        )
+
+
 def _ideas() -> IdeaListResult:
     return IdeaListResult(ideas=[Idea(premise="废柴觉醒系统", hook="开局即巅峰", genre_fit="玄幻")])
 
@@ -106,13 +197,17 @@ def _make_app(
     session: FakeSession | None = None,
     world_repo: _FakeWorldWriteRepo | None = None,
     outline_write_repo: _FakeOutlineWriteRepo | None = None,
+    chapter_repo: _FakeChapterRepo | None = None,
+    outline_read_repo: _FakeOutlineReadRepo | None = None,
     memory: Any = None,
     no_creds: bool = False,
 ) -> tuple[Any, FakeSession, _FakeWorldWriteRepo, _FakeOutlineWriteRepo]:
     os.environ.setdefault("CREDENTIAL_ENC_KEY", Fernet.generate_key().decode())
     from ww_api.main import create_app
     from ww_api.services.project_deps import (
+        get_chapter_repo,
         get_memory_repos,
+        get_outline_read_repo,
         get_outline_write_repo,
         get_project_repo,
         get_tier_gateway_builder,
@@ -123,6 +218,8 @@ def _make_app(
     session = session or FakeSession()
     world_repo = world_repo or _FakeWorldWriteRepo()
     outline_write_repo = outline_write_repo or _FakeOutlineWriteRepo()
+    chapter_repo = chapter_repo or _FakeChapterRepo()
+    outline_read_repo = outline_read_repo or _FakeOutlineReadRepo()
 
     async def _build_ok(_tier: str) -> Any:
         return gateway
@@ -137,6 +234,8 @@ def _make_app(
     )
     app.dependency_overrides[get_world_entity_write_repo] = lambda: world_repo
     app.dependency_overrides[get_outline_write_repo] = lambda: outline_write_repo
+    app.dependency_overrides[get_chapter_repo] = lambda: chapter_repo
+    app.dependency_overrides[get_outline_read_repo] = lambda: outline_read_repo
     app.dependency_overrides[get_session] = lambda: session
     app.dependency_overrides[get_tier_gateway_builder] = lambda: (
         _build_no_creds if no_creds else _build_ok
@@ -180,8 +279,16 @@ async def test_list_toolbox_contains_all_keys() -> None:
         "glossary",
         "opening",
         "fine-outline",
+        "continue",
+        "expand",
+        "de-ai",
+        "teardown",
     }
     by_key = {t["key"]: t for t in tools}
+    # 4 个竞品生成器：非 legacy、纯预览（不可入库）。
+    for key in ("continue", "expand", "de-ai", "teardown"):
+        assert by_key[key]["is_legacy"] is False
+        assert by_key[key]["ingestable"] is False
     # legacy 携 legacy_route + is_legacy；新工具 ingestable 标记。
     assert by_key["worldbuilding"]["is_legacy"] is True
     assert by_key["worldbuilding"]["legacy_route"]
@@ -272,6 +379,121 @@ async def test_generate_no_credentials_503() -> None:
     assert session.commits == 0
 
 
+# ---- POST .../generate（Scope B 竞品快赢：续写/扩写/降AI/拆书）----
+
+
+@pytest.mark.asyncio
+async def test_generate_continue_reads_prior_chapter() -> None:
+    # 续写：端点读该章最新 accepted 正文 → 注入 context（with_prior_chapter 路由）。
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    chapter_repo = _FakeChapterRepo(accepted={2: "他握紧了那柄剑，缓缓转身。"})
+    gateway = _CaptureGateway(ContinuationResult(text="剑光一闪，敌人应声倒地。"))
+    app, session, *_ = _make_app(project_repo=repo, gateway=gateway, chapter_repo=chapter_repo)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/continue/generate", json={"chapter_no": 2, "brief": "续写战斗"}
+        )
+
+    assert resp.status_code == 200
+    body = resp.json()
+    assert body["tool_key"] == "continue"
+    assert body["output_kind"] == "ContinuationResult"
+    assert body["preview"]["text"] == "剑光一闪，敌人应声倒地。"
+    # 前文正文确实进了喂网关的 context（读章路由生效）。
+    assert gateway.last_input is not None
+    assert "他握紧了那柄剑" in gateway.last_input
+    assert session.commits == 1  # 预览不写业务表，落 ledger
+
+
+@pytest.mark.asyncio
+async def test_generate_continue_falls_back_to_draft() -> None:
+    # 无 accepted → 退回草稿正文。
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    chapter_repo = _FakeChapterRepo(drafts={1: "草稿里的开头一段。"})
+    gateway = _CaptureGateway(ContinuationResult(text="续写。"))
+    app, *_ = _make_app(project_repo=repo, gateway=gateway, chapter_repo=chapter_repo)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/continue/generate", json={"chapter_no": 1}
+        )
+
+    assert resp.status_code == 200
+    assert gateway.last_input is not None
+    assert "草稿里的开头一段" in gateway.last_input
+
+
+@pytest.mark.asyncio
+async def test_generate_expand_routes_text_input() -> None:
+    # 扩写：原文经 text 字段 → 注入 context（text_input 路由）。
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    gateway = _CaptureGateway(PolishResult(text="扩写后的丰富正文。"))
+    app, session, *_ = _make_app(project_repo=repo, gateway=gateway)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/expand/generate",
+            json={"text": "原始简短的一句话。", "brief": "加强描写"},
+        )
+
+    assert resp.status_code == 200
+    body = resp.json()
+    assert body["output_kind"] == "PolishResult"
+    assert body["preview"]["text"] == "扩写后的丰富正文。"
+    assert gateway.last_input is not None
+    assert "原始简短的一句话" in gateway.last_input
+    assert session.commits == 1
+
+
+@pytest.mark.asyncio
+async def test_generate_de_ai_routes_text_input() -> None:
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    gateway = _CaptureGateway(DeAiResult(text="更自然的人写质感正文。"))
+    app, *_ = _make_app(project_repo=repo, gateway=gateway)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/de-ai/generate",
+            json={"text": "充斥着 AI 腔的排比句。"},
+        )
+
+    assert resp.status_code == 200
+    assert resp.json()["output_kind"] == "DeAiResult"
+    assert gateway.last_input is not None
+    assert "充斥着 AI 腔的排比句" in gateway.last_input
+
+
+@pytest.mark.asyncio
+async def test_generate_teardown_returns_structured() -> None:
+    repo = FakeProjectRepo()
+    pid = await _seed_project(repo)
+    parsed = BookTeardownResult(
+        themes=["逆袭"],
+        archetypes=["废柴主角"],
+        structure="黄金三章立钩",
+        hooks=["开局即巅峰"],
+    )
+    gateway = _CaptureGateway(parsed)
+    app, *_ = _make_app(project_repo=repo, gateway=gateway)
+
+    async with _client(app) as client:
+        resp = await client.post(
+            f"/projects/{pid}/skills/teardown/generate",
+            json={"kind": "某爆款", "text": "样本章节正文……"},
+        )
+
+    assert resp.status_code == 200
+    body = resp.json()
+    assert body["output_kind"] == "BookTeardownResult"
+    assert body["preview"]["themes"] == ["逆袭"]
+    assert body["preview"]["structure"] == "黄金三章立钩"
+
+
 # ---- POST .../ingest（world_entities gate）----