diff --git a/gateway/api.py b/gateway/api.py
index e810170..63d2c6a 100644
--- a/gateway/api.py
+++ b/gateway/api.py
@@ -201,6 +201,17 @@ try:
     # Vue SPA 静态资源（html=True：对不存在的路径 fallback 到 index.html，支持 SPA 路由）
     app.mount("/static", StaticFiles(directory=str(_STATIC_DIR), html=True), name="static")
 
+    # 校园 AI 代理层（T-P0；D-P7：proxy.enabled=False 时不注册任何 /proxy 路由，
+    # 行为与现状逐字节一致——含本 if 判断在内对既有路径零影响）
+    try:
+        from gateway.proxy import build_proxy_router
+        from gateway.proxy.config import build_proxy_config
+        _proxy_cfg = build_proxy_config(settings_store().to_dict())
+        if _proxy_cfg.enabled:
+            app.include_router(build_proxy_router(_proxy_cfg, get_pool()))
+    except Exception as _pe:  # pragma: no cover - 代理层装配失败不拖垮主应用
+        print(f"[gateway] 代理层未启用（{_pe}）")
+
     @app.get("/", response_class=HTMLResponse, tags=["ui"])
     async def index():
         """Vue SPA 的 index.html（FastAPI API 路由优先，此处仅作 fallback）。"""
diff --git a/gateway/proxy/__init__.py b/gateway/proxy/__init__.py
new file mode 100644
index 0000000..1759235
--- /dev/null
+++ b/gateway/proxy/__init__.py
@@ -0,0 +1,17 @@
+"""校园 AI 代理层（T-P0…T-P8）：/proxy/v1/* 学生面 + /proxy/admin/* 管理面。
+
+组装唯一入口：build_proxy_router(cfg, pool) -> APIRouter；
+由 gateway.api 在 proxy.enabled 时 include（D-P7：关闭时不注册任何路由）。
+"""
+from __future__ import annotations
+
+from fastapi import APIRouter
+
+from gateway.proxy.config import ProxyConfig, build_proxy_config  # noqa: F401
+
+__all__ = ["build_proxy_router", "build_proxy_config", "ProxyConfig"]
+
+
+def build_proxy_router(cfg: ProxyConfig, pool) -> APIRouter:
+    from gateway.proxy.routes import build_proxy_router as _build
+    return _build(cfg, pool)
diff --git a/gateway/proxy/auth.py b/gateway/proxy/auth.py
new file mode 100644
index 0000000..626a5f2
--- /dev/null
+++ b/gateway/proxy/auth.py
@@ -0,0 +1,22 @@
+"""鉴权与限流（T-P1 落地；本文件先立签名）。"""
+from __future__ import annotations
+
+from typing import Any, Dict, Optional
+
+
+def issue_key(ledger, student_id: int, rpm_cap: Optional[int] = None,
+              day_cap_req: Optional[int] = None) -> Dict[str, Any]:
+    """签发学生代理 key：明文只返回一次（T-P1 实现）。"""
+    raise NotImplementedError("T-P1")
+
+
+def authenticate(authorization: str, ledger, limits, now: float) -> Dict[str, Any]:
+    """校验 Bearer key -> 学生上下文（T-P1 实现；带热路径缓存）。"""
+    raise NotImplementedError("T-P1")
+
+
+class RateLimiter:
+    """令牌桶 rpm + per-key 并发信号量（T-P1 实现）。"""
+
+    def allow(self, key_id: int, rpm_cap: int) -> bool:
+        raise NotImplementedError("T-P1")
diff --git a/gateway/proxy/config.py b/gateway/proxy/config.py
new file mode 100644
index 0000000..9868490
--- /dev/null
+++ b/gateway/proxy/config.py
@@ -0,0 +1,164 @@
+"""ProxyConfig：从 settings 的 proxy 段构建代理层配置（T-P0）。
+
+锁定决策落地：
+- D-P1 货币：账本毫元整数。配置里价格是浮点"元/1M tokens"（人类可读），
+  **加载期一次性转为整数毫元/1M tokens**，运行期纯整数运算（毫元漂移只可能
+  发生在这一次换算，黄金用例锁死）。
+- 售价折扣采用差异化 {in: 0.5, out: 0.8}（设计文档 §2.5 结论：统一 5 折
+  盈亏平衡 h0≈32% 结构性危险；执行版 §4 示例与之冲突，按设计文档取差异化，
+  纯配置可热改）。
+- D-P7：enabled=False 时不注册任何 /proxy 路由。
+"""
+from __future__ import annotations
+
+from dataclasses import dataclass, field
+from typing import Any, Dict, List, Optional, Tuple
+
+# 元 -> 毫元换算系数（D-P1：1 元 = 1000 毫元）
+YUAN_TO_MILLI = 1000
+
+
+@dataclass
+class ModelPrice:
+    """单一模型的整数价格表（毫元 / 1M tokens）。"""
+    in_miss: int
+    in_hit: int
+    out: int
+
+
+@dataclass
+class BucketCfg:
+    """一个课程桶的配置。"""
+    name: str
+    system_template: str = "你是校园学习助手。"
+    doc_prefix_file: Optional[str] = None
+    doc_version: int = 1
+    ttl_hours: int = 72
+
+
+@dataclass
+class ProxyConfig:
+    """代理层运行配置（全部为加载期定型值）。"""
+    enabled: bool = False
+    admin_key: str = ""
+    db_path: str = "data/proxy.sqlite3"
+    buckets: Dict[str, BucketCfg] = field(default_factory=dict)
+    model_prices: Dict[str, ModelPrice] = field(default_factory=dict)
+    peak_start: str = "08:30"
+    peak_end: str = "23:59"
+    offpeak_factor: float = 0.5
+    sale_in: float = 0.5
+    sale_out: float = 0.8
+    rpm_per_key: int = 10
+    day_req_cap: int = 200
+    concurrent_per_key: int = 2
+    max_body_chars: int = 60000
+    semcache_enabled: bool = True
+    sim_threshold: float = 0.92
+    max_entries: int = 300000
+    promote_frequency: int = 5
+
+    def bucket(self, name: str) -> BucketCfg:
+        """取桶配置；未知名回落 default（D-P2 缺省桶）。"""
+        if name in self.buckets:
+            return self.buckets[name]
+        return self.buckets.get("default") or BucketCfg(name="default")
+
+    def price(self, model: str) -> Optional[ModelPrice]:
+        """取模型价格表；未配置返回 None（调用方应拒绝或用 default 档）。"""
+        return self.model_prices.get(model)
+
+
+def _to_milli_per_m(yuan_per_m: float) -> int:
+    """元/1M -> 毫元/1M（四舍五入取整，加载期唯一换算点）。"""
+    return int(round(float(yuan_per_m) * YUAN_TO_MILLI))
+
+
+def _parse_hhmm(text: str, fallback: str) -> str:
+    """校验 HH:MM 形态，非法回落默认。"""
+    t = str(text or fallback).strip()
+    parts = t.split(":")
+    if len(parts) == 2 and parts[0].isdigit() and parts[1].isdigit():
+        h, m = int(parts[0]), int(parts[1])
+        if 0 <= h <= 23 and 0 <= m <= 59:
+            return f"{h:02d}:{m:02d}"
+    return fallback
+
+
+def build_proxy_config(settings_dict: Dict[str, Any]) -> ProxyConfig:
+    """从 settings.to_dict() 的 proxy 段构建 ProxyConfig（缺省值兜底）。
+
+    settings_dict 为整个设置 dict（含 worker/architect/... 与 proxy 段）。
+    """
+    raw = settings_dict.get("proxy") or {}
+    if not isinstance(raw, dict):
+        raw = {}
+
+    # ---- 桶 ----
+    buckets: Dict[str, BucketCfg] = {}
+    raw_buckets = raw.get("buckets") or {}
+    if isinstance(raw_buckets, dict):
+        for name, b in raw_buckets.items():
+            if not isinstance(b, dict):
+                continue
+            buckets[str(name)] = BucketCfg(
+                name=str(name),
+                system_template=str(b.get("system_template") or "你是校园学习助手。"),
+                doc_prefix_file=(str(b["doc_prefix_file"])
+                                 if b.get("doc_prefix_file") else None),
+                doc_version=int(b.get("doc_version", 1) or 1),
+                ttl_hours=int(b.get("ttl_hours", 72) or 72),
+            )
+    if "default" not in buckets:
+        buckets["default"] = BucketCfg(name="default")
+
+    # ---- 价格表：元/1M 浮点 -> 毫元/1M 整数（D-P1 加载期换算） ----
+    model_prices: Dict[str, ModelPrice] = {}
+    raw_pricing = raw.get("pricing") or {}
+    if isinstance(raw_pricing, dict):
+        for model, p in raw_pricing.items():
+            if not isinstance(p, dict) or "in_miss" not in p:
+                continue  # peak_window/offpeak_factor/sale_discount 非模型键
+            in_miss = _to_milli_per_m(p.get("in_miss", 0))
+            in_hit = _to_milli_per_m(p.get("in_hit", 0))
+            out = _to_milli_per_m(p.get("out", 0))
+            if in_miss <= 0:
+                continue
+            if in_hit <= 0:
+                in_hit = max(1, in_miss // 30)   # 缺省 = in_miss × 1/30（D-P3）
+            model_prices[str(model)] = ModelPrice(
+                in_miss=in_miss, in_hit=in_hit, out=out)
+
+    # ---- 峰谷窗口 / 系数 ----
+    pw = raw_pricing.get("peak_window") or {} if isinstance(raw_pricing, dict) else {}
+    off = float(raw_pricing.get("offpeak_factor", 0.5)) if isinstance(raw_pricing, dict) else 0.5
+    sale = raw_pricing.get("sale_discount") or {} if isinstance(raw_pricing, dict) else {}
+
+    # ---- 限流 / 缓存 ----
+    limits = raw.get("limits") or {}
+    if not isinstance(limits, dict):
+        limits = {}
+    sem = raw.get("semcache") or {}
+    if not isinstance(sem, dict):
+        sem = {}
+
+    return ProxyConfig(
+        enabled=bool(raw.get("enabled", False)),
+        admin_key=str(raw.get("admin_key") or ""),
+        db_path=str(raw.get("db_path") or "data/proxy.sqlite3"),
+        buckets=buckets,
+        model_prices=model_prices,
+        peak_start=_parse_hhmm(pw.get("start"), "08:30") if isinstance(pw, dict) else "08:30",
+        peak_end=_parse_hhmm(pw.get("end"), "23:59") if isinstance(pw, dict) else "23:59",
+        offpeak_factor=max(0.0, min(1.0, off)),
+        sale_in=max(0.0, min(1.0, float(sale.get("in", 0.5)))),
+        sale_out=max(0.0, min(1.0, float(sale.get("out", 0.8)))),
+        rpm_per_key=int(limits.get("rpm_per_key", 10) or 10),
+        day_req_cap=int(limits.get("day_req_cap", 200) or 200),
+        concurrent_per_key=int(limits.get("concurrent_per_key", 2) or 2),
+        max_body_chars=int(limits.get("max_body_chars", 60000) or 60000),
+        semcache_enabled=bool(sem.get("enabled", True)),
+        sim_threshold=float(sem.get("sim_threshold", 0.92) or 0.92),
+        max_entries=int(sem.get("max_entries", 300000) or 300000),
+        promote_frequency=int(sem.get("promote_frequency", 5) or 5),
+    )
diff --git a/gateway/proxy/errors.py b/gateway/proxy/errors.py
new file mode 100644
index 0000000..87d74b7
--- /dev/null
+++ b/gateway/proxy/errors.py
@@ -0,0 +1,50 @@
+"""代理层错误类型（§5.3 错误码映射）。"""
+from __future__ import annotations
+
+
+class ProxyError(Exception):
+    """代理层错误基类（HTTP 语义由子类表达）。"""
+    status_code = 500
+    code = "proxy_error"
+
+
+class ProxyAuthError(ProxyError):
+    """无效/注销 key。"""
+    status_code = 401
+    code = "invalid_key"
+
+
+class BalanceError(ProxyError):
+    """余额或日上限不足（预扣失败）。"""
+    status_code = 402
+    code = "insufficient_balance"
+
+
+class SuspendedError(ProxyError):
+    """学生账户被停用。"""
+    status_code = 403
+    code = "student_suspended"
+
+
+class QuotaError(ProxyError):
+    """限流（rpm / 日请求上限 / 并发上限）。"""
+    status_code = 429
+    code = "rate_limited"
+
+
+class BodyTooLargeError(ProxyError):
+    """请求体超过 max_body_chars。"""
+    status_code = 413
+    code = "body_too_large"
+
+
+class UpstreamError(ProxyError):
+    """上游失败（首 token 前 failover 均失败）。"""
+    status_code = 502
+    code = "upstream_failed"
+
+
+class AdminAuthError(ProxyError):
+    """管理面鉴权失败。"""
+    status_code = 401
+    code = "admin_unauthorized"
diff --git a/gateway/proxy/ledger.py b/gateway/proxy/ledger.py
new file mode 100644
index 0000000..6cb68f0
--- /dev/null
+++ b/gateway/proxy/ledger.py
@@ -0,0 +1,92 @@
+"""账本（T-P0：DDL 初始化 + 连接纪律；CRUD/预扣在 T-P1 落地）。
+
+工程纪律：
+- D-P10：sqlite3 是同步库，所有 DB 调用必须经 asyncio.to_thread（由调用方
+  routes 层包装；本模块保持同步实现，可测试性好）。连接 check_same_thread=False
+  + threading.Lock 串行化（沿用 ReviewQueue 模式：每操作新连接 + 全局锁）。
+- WAL 模式（§3）。
+- D-P11：预扣用原子 UPDATE，见 try_hold（T-P1 实现）。
+"""
+from __future__ import annotations
+
+import sqlite3
+import threading
+from pathlib import Path
+from typing import Any, Dict, List, Optional
+
+# 四表 + 两索引（§3，一字不改）
+_SCHEMA = """
+CREATE TABLE IF NOT EXISTS students(
+  id INTEGER PRIMARY KEY, name TEXT NOT NULL, class TEXT DEFAULT '',
+  status TEXT NOT NULL DEFAULT 'active',
+  balance_milli INTEGER NOT NULL DEFAULT 0,
+  daily_cap_milli INTEGER NOT NULL DEFAULT 5000,
+  spent_today_milli INTEGER NOT NULL DEFAULT 0, spent_date TEXT DEFAULT '');
+
+CREATE TABLE IF NOT EXISTS proxy_keys(
+  id INTEGER PRIMARY KEY, key_hash TEXT UNIQUE NOT NULL, key_prefix TEXT NOT NULL,
+  student_id INTEGER NOT NULL REFERENCES students(id),
+  created_ts INTEGER NOT NULL, revoked INTEGER NOT NULL DEFAULT 0,
+  rpm_cap INTEGER NOT NULL DEFAULT 10, day_cap_req INTEGER NOT NULL DEFAULT 200,
+  req_today INTEGER NOT NULL DEFAULT 0, req_date TEXT DEFAULT '');
+
+CREATE TABLE IF NOT EXISTS usage_ledger(
+  request_id TEXT PRIMARY KEY, ts INTEGER NOT NULL, key_id INTEGER NOT NULL,
+  model TEXT NOT NULL, bucket TEXT NOT NULL DEFAULT 'default',
+  in_miss_tok INTEGER NOT NULL DEFAULT 0, in_hit_tok INTEGER NOT NULL DEFAULT 0,
+  out_tok INTEGER NOT NULL DEFAULT 0, gateway_cached INTEGER NOT NULL DEFAULT 0,
+  upstream_cost_milli INTEGER NOT NULL DEFAULT 0, charged_milli INTEGER NOT NULL DEFAULT 0,
+  margin_milli INTEGER NOT NULL DEFAULT 0, ttfb_ms INTEGER, total_ms INTEGER,
+  status TEXT NOT NULL);
+
+CREATE TABLE IF NOT EXISTS semcache(
+  cache_key TEXT PRIMARY KEY,
+  bucket TEXT NOT NULL, q_norm TEXT NOT NULL, answer TEXT NOT NULL, model TEXT NOT NULL,
+  created_ts INTEGER NOT NULL, ttl_ts INTEGER NOT NULL,
+  doc_version INTEGER NOT NULL DEFAULT 1, hits INTEGER NOT NULL DEFAULT 0);
+CREATE INDEX IF NOT EXISTS idx_semcache_bucket ON semcache(bucket, ttl_ts);
+CREATE INDEX IF NOT EXISTS idx_ledger_ts ON usage_ledger(ts);
+"""
+
+_TABLES = ("students", "proxy_keys", "usage_ledger", "semcache")
+
+
+class Ledger:
+    """代理层账本（sqlite WAL；同步实现，调用方负责 to_thread）。"""
+
+    def __init__(self, db_path: str | Path):
+        self.db_path = Path(db_path)
+        self.db_path.parent.mkdir(parents=True, exist_ok=True)
+        self._lock = threading.Lock()
+        self._init_db()
+
+    # ---------- 初始化 ----------
+    @classmethod
+    def init_db(cls, db_path: str | Path) -> "Ledger":
+        """工厂（§6 签名）：建库建表（幂等）。"""
+        return cls(db_path)
+
+    def _connect(self) -> sqlite3.Connection:
+        conn = sqlite3.connect(self.db_path, check_same_thread=False)
+        conn.row_factory = sqlite3.Row
+        conn.execute("PRAGMA journal_mode=WAL")
+        return conn
+
+    def _init_db(self) -> None:
+        with self._lock, self._connect() as conn:
+            conn.executescript(_SCHEMA)
+
+    # ---------- 自省（T-P0 验收用） ----------
+    def table_names(self) -> List[str]:
+        """列出已建表名（测试验收）。"""
+        with self._lock, self._connect() as conn:
+            rows = conn.execute(
+                "SELECT name FROM sqlite_master WHERE type='table'").fetchall()
+        return [r["name"] for r in rows]
+
+    def index_names(self) -> List[str]:
+        with self._lock, self._connect() as conn:
+            rows = conn.execute(
+                "SELECT name FROM sqlite_master WHERE type='index' AND name LIKE 'idx_%'"
+            ).fetchall()
+        return [r["name"] for r in rows]
diff --git a/gateway/proxy/normalizer.py b/gateway/proxy/normalizer.py
new file mode 100644
index 0000000..6b963ff
--- /dev/null
+++ b/gateway/proxy/normalizer.py
@@ -0,0 +1,19 @@
+"""请求规范化与桶解析（T-P5 落地；本文件先立签名）。"""
+from __future__ import annotations
+
+from typing import Any, Dict
+
+
+def resolve_bucket(body: dict, headers: dict, cfg) -> Any:
+    """解析课程桶：X-Campus-Bucket 头 > model->bucket 映射 > default（T-P5 实现）。"""
+    raise NotImplementedError("T-P5")
+
+
+def canonical_hash(bucket: str, doc_version: int, body: dict) -> str:
+    """规范化哈希：稳定序列化 -> sha256（五规则见 §6；T-P5 实现）。"""
+    raise NotImplementedError("T-P5")
+
+
+def shape(body: dict, bucket_cfg) -> dict:
+    """整形上游请求体：[canonical_system] -> [doc_prefix] -> [原 messages]（T-P5 实现）。"""
+    raise NotImplementedError("T-P5")
diff --git a/gateway/proxy/pricing.py b/gateway/proxy/pricing.py
new file mode 100644
index 0000000..a3da201
--- /dev/null
+++ b/gateway/proxy/pricing.py
@@ -0,0 +1,17 @@
+"""计价（T-P3 落地；本文件先立签名）。
+
+D-P1：compute 输入输出全为整数毫元；配置换算在 config 加载期完成。
+"""
+from __future__ import annotations
+
+from typing import Any, Dict
+
+
+def is_offpeak(ts: float, peak_start: str, peak_end: str) -> bool:
+    """峰谷窗口判定（本地时区 HH:MM；T-P3 实现）。"""
+    raise NotImplementedError("T-P3")
+
+
+def compute(usage: Dict[str, int], model: str, ts: float, cfg) -> Dict[str, int]:
+    """按 usage 计费 -> {upstream_cost_milli, charged_milli, margin_milli}（T-P3 实现）。"""
+    raise NotImplementedError("T-P3")
diff --git a/gateway/proxy/routes.py b/gateway/proxy/routes.py
new file mode 100644
index 0000000..ac73e68
--- /dev/null
+++ b/gateway/proxy/routes.py
@@ -0,0 +1,28 @@
+"""代理面路由（T-P0 骨架：/proxy/v1/models；主对话路由 T-P4 落地）。"""
+from __future__ import annotations
+
+from fastapi import APIRouter, Request
+
+from gateway.proxy.config import ProxyConfig
+
+
+def build_proxy_router(cfg: ProxyConfig, pool) -> APIRouter:
+    """组装代理面路由（唯一组装点；pool 为 gateway.model_pool.PoolStore）。"""
+    router = APIRouter(prefix="/proxy")
+
+    @router.get("/v1/models", tags=["proxy"])
+    async def list_models():
+        """学生面：池内允许代理的模型列表（OpenAI /models 形状）。"""
+        entries = pool.list().get("entries", [])
+        names = [e["model"] for e in entries
+                 if e.get("enabled") and e.get("backend") not in ("mock",)]
+        # 去重保序
+        seen, data = set(), []
+        for n in names:
+            if n not in seen:
+                seen.add(n)
+                data.append({"id": n, "object": "model", "owned_by": "campus-proxy"})
+        return {"object": "list", "data": data}
+
+    # /v1/chat/completions 与 /admin/* 在 T-P1/T-P4 追加
+    return router
diff --git a/gateway/proxy/semcache.py b/gateway/proxy/semcache.py
new file mode 100644
index 0000000..00fd821
--- /dev/null
+++ b/gateway/proxy/semcache.py
@@ -0,0 +1,24 @@
+"""语义缓存（T-P6 落地；本文件先立签名）。
+
+规格（§6）：L1 精确 + L2 字符 2/3-gram 倒排（启动自 sqlite 重建），
+加权 Jaccard（3-gram 权 2）+ 共享 gram>=3 门限 + 阈值 0.92，
+TTL + LRU(max_entries)，L2 命中 promote_frequency 次晋升 L1。
+"""
+from __future__ import annotations
+
+from typing import Any, Dict, Optional
+
+
+class SemanticCache:
+    """两级语义缓存（T-P6 实现）。"""
+
+    def lookup(self, bucket: str, doc_version: int, norm_hash: str,
+               norm_text: str, now: float) -> Optional[Dict[str, Any]]:
+        raise NotImplementedError("T-P6")
+
+    def put(self, bucket: str, doc_version: int, norm_hash: str,
+            norm_text: str, answer: str, model: str, now: float) -> None:
+        raise NotImplementedError("T-P6")
+
+    def stats(self) -> Dict[str, Any]:
+        raise NotImplementedError("T-P6")
diff --git a/gateway/proxy/upstream.py b/gateway/proxy/upstream.py
new file mode 100644
index 0000000..c6370cc
--- /dev/null
+++ b/gateway/proxy/upstream.py
@@ -0,0 +1,21 @@
+"""上游客户端（T-P2 落地；本文件先立签名）。
+
+规格（§6）：模块级 httpx.AsyncClient 单例（keepalive，max_connections=100），
+超时 connect=10s/read=120s/write=10s/pool=30s；始终注入
+stream_options.include_usage（客户端未要求 usage 时过滤该 chunk 不下发）；
+首 token 前 failover（D-P4）。
+"""
+from __future__ import annotations
+
+from typing import Any, AsyncIterator, Dict
+
+
+async def stream(body: dict, entry: Dict[str, Any], usage_sink) -> AsyncIterator[bytes]:
+    """流式派发到上游，逐块 yield（T-P2 实现）。"""
+    raise NotImplementedError("T-P2")
+    yield b""  # pragma: no cover
+
+
+def normalize_usage(provider: str, usage_dict: Dict[str, Any]) -> Dict[str, int]:
+    """三家 usage 字段 -> 统一 {in_miss, in_hit, out}（T-P2 实现）。"""
+    raise NotImplementedError("T-P2")
diff --git a/gateway/settings.py b/gateway/settings.py
index 889e8d6..cd177e9 100644
--- a/gateway/settings.py
+++ b/gateway/settings.py
@@ -48,6 +48,26 @@ DEFAULTS: Dict[str, Any] = {
         "approval_policy": "dangerous",      # 审批策略：off | dangerous（写/编辑/命令询问）| all
         "approval_timeout_s": 120,           # 审批等待超时（超时自动拒绝）
     },
+    # 校园 AI 代理层（T-P0；结构见《实施方案_代理层与缓存层.md》§4）
+    "proxy": {
+        "enabled": False,                    # D-P7：默认关，开启需显式配置（重启生效）
+        "admin_key": "",                     # 管理面密钥；空 = 仅 loopback 放行
+        "db_path": "data/proxy.sqlite3",
+        "buckets": {                         # 桶配置（嵌套对象原样存储）
+            "default": {"system_template": "你是校园学习助手。",
+                        "doc_prefix_file": None, "doc_version": 1, "ttl_hours": 72},
+        },
+        "pricing": {                         # 元/1M tokens（加载期转毫元整数，D-P1）
+            "deepseek-chat": {"in_miss": 3.0, "in_hit": 0.1, "out": 9.0},
+            "peak_window": {"start": "08:30", "end": "23:59"},
+            "offpeak_factor": 0.5,
+            "sale_discount": {"in": 0.5, "out": 0.8},   # 差异化（设计文档 §2.5）
+        },
+        "limits": {"rpm_per_key": 10, "day_req_cap": 200,
+                   "concurrent_per_key": 2, "max_body_chars": 60000},
+        "semcache": {"enabled": True, "sim_threshold": 0.92,
+                     "max_entries": 300000, "promote_frequency": 5},
+    },
 }
 
 
diff --git a/scripts/serve.py b/scripts/serve.py
index d9ff253..c3f26c7 100644
--- a/scripts/serve.py
+++ b/scripts/serve.py
@@ -19,6 +19,13 @@ def start(port: int):
         if old:
             print(f"已有服务运行 (pid={old})，先执行 --stop 再启动。")
             return
+    # D-P9：代理层（singleflight/令牌桶/内存 LRU）为进程内状态，多 worker 会静默失效
+    for var in ("WEB_CONCURRENCY", "UVICORN_WORKERS"):
+        v = (os.environ.get(var) or "").strip()
+        if v.isdigit() and int(v) > 1:
+            print(f"拒绝启动：{var}={v}。代理层要求单进程（workers=1），"
+                  "扩容路径见《实施方案_代理层与缓存层.md》D-P9。")
+            return
     out = open(ROOT / "_gateway.out.log", "ab", buffering=0)
     err = open(ROOT / "_gateway.err.log", "ab", buffering=0)
     flags = 0x00000008 | 0x08000000  # DETACHED_PROCESS | CREATE_NO_WINDOW
diff --git a/tests/test_proxy_routes.py b/tests/test_proxy_routes.py
new file mode 100644
index 0000000..fb30328
--- /dev/null
+++ b/tests/test_proxy_routes.py
@@ -0,0 +1,87 @@
+"""代理层骨架测试（T-P0）：enabled 门控 / DDL / 独立挂载的 models 端点。"""
+import pytest
+
+pytest.importorskip("fastapi")
+
+from fastapi import FastAPI
+from fastapi.testclient import TestClient
+
+import gateway.api as ga
+from gateway.proxy.config import ProxyConfig, build_proxy_config
+from gateway.proxy.ledger import Ledger
+
+
+def test_proxy_disabled_by_default_404():
+    """D-P7：默认 enabled=False -> 全局 app 不注册任何 /proxy 路由。"""
+    client = TestClient(ga.app)
+    assert client.get("/proxy/v1/models").status_code == 404
+    assert client.post("/proxy/v1/chat/completions", json={}).status_code == 404
+    assert client.get("/proxy/admin/stats").status_code == 404
+
+
+def test_ddl_creates_tables_and_indexes(tmp_path):
+    """四表 + 两索引幂等创建（WAL）。"""
+    led = Ledger.init_db(tmp_path / "proxy.sqlite3")
+    tables = set(led.table_names())
+    for t in ("students", "proxy_keys", "usage_ledger", "semcache"):
+        assert t in tables
+    idx = set(led.index_names())
+    assert "idx_semcache_bucket" in idx
+    assert "idx_ledger_ts" in idx
+    # 幂等重建
+    led2 = Ledger.init_db(tmp_path / "proxy.sqlite3")
+    assert "semcache" in set(led2.table_names())
+
+
+def test_build_proxy_config_defaults_and_milli_conversion():
+    """缺省值兜底 + 元/1M -> 毫元/1M 加载期换算（D-P1）。"""
+    from gateway.settings import DEFAULTS
+    cfg = build_proxy_config(DEFAULTS)      # DEFAULTS 自带 deepseek-chat 价格示例
+    assert cfg.enabled is False
+    assert "default" in cfg.buckets
+    assert cfg.sale_in == 0.5 and cfg.sale_out == 0.8     # 差异化定价
+    # 自带 DEFAULTS 的 deepseek-chat 价格：3.0 元 -> 3000 毫元
+    p = cfg.price("deepseek-chat")
+    assert p is not None
+    assert p.in_miss == 3000
+    assert p.in_hit == 100            # 0.1 元 -> 100 毫元
+    assert p.out == 9000
+
+    # in_hit 缺省 = in_miss / 30（D-P3）
+    cfg2 = build_proxy_config({"proxy": {
+        "pricing": {"some-model": {"in_miss": 3.0, "out": 9.0}}}})
+    p2 = cfg2.price("some-model")
+    assert p2.in_hit == 100           # 3000 // 30
+
+    # 桶解析回落 default
+    assert cfg.bucket("ghost").name == "default"
+
+
+def test_enabled_router_lists_pool_models(tmp_path, monkeypatch):
+    """enabled=True 独立挂载：/proxy/v1/models 返回池内非 mock 模型（OpenAI 形状）。"""
+    import gateway.model_pool as mp
+    from gateway.model_pool import PoolStore
+    mp.reset_pool()
+    monkeypatch.setattr(mp, "_store", PoolStore(path=tmp_path / "pool.json"))
+    mp.get_pool().upsert({
+        "id": "up1", "name": "云端", "tier": "budget", "backend": "openai",
+        "base_url": "https://api.example.com", "model": "deepseek-chat",
+        "price_in": 0.1, "price_out": 0.1, "enabled": True})
+    mp.get_pool().upsert({
+        "id": "mk", "name": "模拟", "tier": "local", "backend": "mock",
+        "model": "mock", "enabled": True})            # mock 不应出现
+
+    cfg = build_proxy_config({"proxy": {"enabled": True,
+                                        "db_path": str(tmp_path / "p.sqlite3")}})
+    app = FastAPI()
+    app.include_router(__import__("gateway.proxy", fromlist=["x"]).build_proxy_router(
+        cfg, mp.get_pool()))
+    client = TestClient(app)
+    r = client.get("/proxy/v1/models")
+    assert r.status_code == 200
+    data = r.json()
+    assert data["object"] == "list"
+    ids = [m["id"] for m in data["data"]]
+    assert ids == ["deepseek-chat"]
+    assert data["data"][0]["owned_by"] == "campus-proxy"
+    mp.reset_pool()
diff --git a/任务拆解与执行计划.md b/任务拆解与执行计划.md
index 79b4b8e..428b12a 100644
--- a/任务拆解与执行计划.md
+++ b/任务拆解与执行计划.md
@@ -135,7 +135,7 @@ P0 完成后的能力：干净的后端抽象 + 可量化的评测 + 可追溯
 
 | T | 内容 | 状态 | commit |
 |---|------|------|--------|
-| T-P0 | 骨架：gateway/proxy/ 包 + SQLite DDL + enabled 门控挂路由 | ⬜ 待办 | |
+| T-P0 | 骨架：gateway/proxy/ 包 + SQLite DDL + enabled 门控挂路由 | ✅ 完成 | T-P0 |
 | T-P1 | 鉴权+账本：key 签发/令牌桶/四表/request_id 幂等/日限额 | ⬜ 待办 | |
 | T-P2 | 上游客户端：流式派发+三家 usage 归一化+首 token 前 failover | ⬜ 待办 | |
 | T-P3 | 计价+结算：峰谷窗口/毫元整数/黄金用例 ≥10 组 | ⬜ 待办 | |