diff --git a/backend/app.py b/backend/app.py
index d8212b2..1254eb3 100644
--- a/backend/app.py
+++ b/backend/app.py
@@ -18,7 +18,14 @@ from db.session import init_db
 from fastapi import FastAPI
 from fastapi.middleware.cors import CORSMiddleware
 
-from routes import assistants, credentials, health, voice_webrtc, voice_ws
+from routes import (
+    assistants,
+    credentials,
+    health,
+    knowledge_bases,
+    voice_webrtc,
+    voice_ws,
+)
 
 
 @asynccontextmanager
@@ -40,6 +47,7 @@ app.add_middleware(
 app.include_router(health.router)
 app.include_router(assistants.router)
 app.include_router(credentials.router)
+app.include_router(knowledge_bases.router)
 app.include_router(voice_webrtc.router)
 app.include_router(voice_ws.router)
 
diff --git a/backend/db/models.py b/backend/db/models.py
index f9adf08..506c1ee 100644
--- a/backend/db/models.py
+++ b/backend/db/models.py
@@ -9,7 +9,7 @@
 
 from datetime import datetime
 
-from sqlalchemy import Boolean, DateTime, String, func
+from sqlalchemy import JSON, Boolean, DateTime, ForeignKey, String, func
 from sqlalchemy.orm import DeclarativeBase, Mapped, mapped_column
 
 
@@ -37,19 +37,67 @@ class ProviderCredential(Base):
     )
 
 
-class Assistant(Base):
-    __tablename__ = "assistants"
+class KnowledgeBase(Base):
+    """知识库注册表。本身引用一个 Embedding 凭证(用哪个向量模型)。
 
-    id: Mapped[str] = mapped_column(String(40), primary_key=True)  # asst_xxx
+    文档/分块(pgvector)是 KB 内部实现,这里先不展开;助手侧只认 knowledge_base_id。
+    """
+
+    __tablename__ = "knowledge_bases"
+
+    id: Mapped[str] = mapped_column(String(40), primary_key=True)  # kb_xxx
     name: Mapped[str] = mapped_column(String(128))
-    greeting: Mapped[str] = mapped_column(String(2048), default="")
-    prompt: Mapped[str] = mapped_column(String(8192), default="")
-    runtime_mode: Mapped[str] = mapped_column(String(16), default="pipeline")
-    # 模型/音色的"选项名",不是 key
-    model: Mapped[str] = mapped_column(String(128), default="")
-    asr: Mapped[str] = mapped_column(String(128), default="")
-    voice: Mapped[str] = mapped_column(String(128), default="")
-    enable_interrupt: Mapped[bool] = mapped_column(Boolean, default=True)
+    description: Mapped[str] = mapped_column(String(2048), default="")
+    # 该 KB 用哪个向量模型;凭证被删则置空
+    embedding_credential_id: Mapped[str | None] = mapped_column(
+        String(40),
+        ForeignKey("provider_credentials.id", ondelete="SET NULL"),
+        nullable=True,
+    )
+    status: Mapped[str] = mapped_column(String(16), default="active")  # active|archived
+    created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
+    updated_at: Mapped[datetime] = mapped_column(
+        DateTime(timezone=True), server_default=func.now(), onupdate=func.now()
+    )
+
+
+class Assistant(Base):
+    """助手(单表,无版本化)。type 为可变普通列,5 种类型共用此表。
+
+    模型/KB 以 FK 引用注册表;类型专属字段塞进 config(JSON)。
+    """
+
+    __tablename__ = "assistants"
+
+    id: Mapped[str] = mapped_column(String(40), primary_key=True)  # asst_xxx
+    name: Mapped[str] = mapped_column(String(128))
+    # prompt|workflow|dify|fastgpt|opencode;创建后可改
+    type: Mapped[str] = mapped_column(String(16), index=True, default="prompt")
+    runtime_mode: Mapped[str] = mapped_column(String(16), default="pipeline")
+    greeting: Mapped[str] = mapped_column(String(2048), default="")
+    enable_interrupt: Mapped[bool] = mapped_column(Boolean, default=True)
+
+    # ---- 引用"注册好的资源":凭证被删 → SET NULL(resolver 有默认/.env 兜底) ----
+    llm_credential_id: Mapped[str | None] = mapped_column(
+        String(40), ForeignKey("provider_credentials.id", ondelete="SET NULL"), nullable=True
+    )
+    asr_credential_id: Mapped[str | None] = mapped_column(
+        String(40), ForeignKey("provider_credentials.id", ondelete="SET NULL"), nullable=True
+    )
+    tts_credential_id: Mapped[str | None] = mapped_column(
+        String(40), ForeignKey("provider_credentials.id", ondelete="SET NULL"), nullable=True
+    )
+    realtime_credential_id: Mapped[str | None] = mapped_column(
+        String(40), ForeignKey("provider_credentials.id", ondelete="SET NULL"), nullable=True
+    )
+    # KB 引用:被引用时禁止删 KB(RESTRICT),无默认兜底
+    knowledge_base_id: Mapped[str | None] = mapped_column(
+        String(40), ForeignKey("knowledge_bases.id", ondelete="RESTRICT"), nullable=True
+    )
+
+    # 类型专属字段(形态各异):prompt / graph / dify|fastgpt|opencode 端点+key(打码)
+    config: Mapped[dict] = mapped_column(JSON, default=dict)
+
     created_at: Mapped[datetime] = mapped_column(DateTime(timezone=True), server_default=func.now())
     updated_at: Mapped[datetime] = mapped_column(
         DateTime(timezone=True), server_default=func.now(), onupdate=func.now()
diff --git a/backend/routes/assistants.py b/backend/routes/assistants.py
index f5db498..a570732 100644
--- a/backend/routes/assistants.py
+++ b/backend/routes/assistants.py
@@ -1,6 +1,7 @@
 """助手 CRUD。前端「助手列表 / 创建 / 编辑」对接这里。
 
-助手配置不含 key,所以无需打码。
+模型/KB 以 FK 引用注册表;外部类型(dify/fastgpt/opencode)的 config.apiKey 是私有密钥,
+读时打码、写时哨兵(复用 services/masking)。
 """
 
 import uuid
@@ -8,24 +9,47 @@ import uuid
 from db.models import Assistant
 from db.session import get_session
 from fastapi import APIRouter, Depends, HTTPException
-from schemas import AssistantOut, AssistantUpsert
+from schemas import EXTERNAL_TYPES, AssistantOut, AssistantUpsert
+from services.masking import mask, resolve_incoming_key
 from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 router = APIRouter(prefix="/api/assistants", tags=["assistants"])
 
 
+def _mask_config(type_: str, config: dict) -> dict:
+    """读取返回前:外部类型的 apiKey 打码,其余原样。"""
+    if type_ in EXTERNAL_TYPES and config.get("apiKey"):
+        return {**config, "apiKey": mask(config["apiKey"])}
+    return config
+
+
+def _merge_config(type_: str, incoming: dict, stored: dict) -> dict:
+    """写入时:外部类型若回传打码占位符/空 apiKey → 保留旧 key。"""
+    if type_ in EXTERNAL_TYPES and "apiKey" in incoming:
+        incoming = {
+            **incoming,
+            "apiKey": resolve_incoming_key(
+                incoming.get("apiKey"), stored.get("apiKey", "")
+            ),
+        }
+    return incoming
+
+
 def _to_out(a: Assistant) -> AssistantOut:
     return AssistantOut(
         id=a.id,
         name=a.name,
-        greeting=a.greeting,
-        prompt=a.prompt,
+        type=a.type,  # type: ignore[arg-type]
         runtime_mode=a.runtime_mode,  # type: ignore[arg-type]
-        model=a.model,
-        asr=a.asr,
-        voice=a.voice,
+        greeting=a.greeting,
         enable_interrupt=a.enable_interrupt,
+        llm_credential_id=a.llm_credential_id,
+        asr_credential_id=a.asr_credential_id,
+        tts_credential_id=a.tts_credential_id,
+        realtime_credential_id=a.realtime_credential_id,
+        knowledge_base_id=a.knowledge_base_id,
+        config=_mask_config(a.type, a.config or {}),
         updated_at=a.updated_at.isoformat() if a.updated_at else None,
     )
 
@@ -68,7 +92,10 @@ async def update_assistant(
     a = await session.get(Assistant, assistant_id)
     if not a:
         raise HTTPException(404, "助手不存在")
-    for k, v in body.model_dump().items():
+    data = body.model_dump()
+    # 外部类型 apiKey 写时哨兵:打码占位符 → 保留旧 key(在改 a.config 前用旧值)
+    data["config"] = _merge_config(body.type, data["config"], a.config or {})
+    for k, v in data.items():
         setattr(a, k, v)
     await session.commit()
     await session.refresh(a)
diff --git a/backend/routes/knowledge_bases.py b/backend/routes/knowledge_bases.py
new file mode 100644
index 0000000..4356d2a
--- /dev/null
+++ b/backend/routes/knowledge_bases.py
@@ -0,0 +1,90 @@
+"""知识库 CRUD。前端助手编辑页的"知识库"下拉对接这里。
+
+KB 自身引用一个 Embedding 凭证(embeddingCredentialId)。被助手引用时禁止删除
+(DB 层 ON DELETE RESTRICT),这里把外键冲突翻译成 409。
+"""
+
+import uuid
+
+from db.models import KnowledgeBase
+from db.session import get_session
+from fastapi import APIRouter, Depends, HTTPException
+from schemas import KnowledgeBaseOut, KnowledgeBaseUpsert
+from sqlalchemy import select
+from sqlalchemy.exc import IntegrityError
+from sqlalchemy.ext.asyncio import AsyncSession
+
+router = APIRouter(prefix="/api/knowledge-bases", tags=["knowledge-bases"])
+
+
+def _to_out(kb: KnowledgeBase) -> KnowledgeBaseOut:
+    return KnowledgeBaseOut(
+        id=kb.id,
+        name=kb.name,
+        description=kb.description,
+        embedding_credential_id=kb.embedding_credential_id,
+        status=kb.status,
+        updated_at=kb.updated_at.isoformat() if kb.updated_at else None,
+    )
+
+
+@router.get("", response_model=list[KnowledgeBaseOut])
+async def list_knowledge_bases(session: AsyncSession = Depends(get_session)):
+    rows = (
+        await session.execute(select(KnowledgeBase).order_by(KnowledgeBase.name))
+    ).scalars().all()
+    return [_to_out(kb) for kb in rows]
+
+
+@router.post("", response_model=KnowledgeBaseOut)
+async def create_knowledge_base(
+    body: KnowledgeBaseUpsert, session: AsyncSession = Depends(get_session)
+):
+    kb = KnowledgeBase(id=f"kb_{uuid.uuid4().hex[:12]}", **body.model_dump())
+    session.add(kb)
+    await session.commit()
+    await session.refresh(kb)
+    return _to_out(kb)
+
+
+@router.get("/{kb_id}", response_model=KnowledgeBaseOut)
+async def get_knowledge_base(
+    kb_id: str, session: AsyncSession = Depends(get_session)
+):
+    kb = await session.get(KnowledgeBase, kb_id)
+    if not kb:
+        raise HTTPException(404, "知识库不存在")
+    return _to_out(kb)
+
+
+@router.put("/{kb_id}", response_model=KnowledgeBaseOut)
+async def update_knowledge_base(
+    kb_id: str,
+    body: KnowledgeBaseUpsert,
+    session: AsyncSession = Depends(get_session),
+):
+    kb = await session.get(KnowledgeBase, kb_id)
+    if not kb:
+        raise HTTPException(404, "知识库不存在")
+    for k, v in body.model_dump().items():
+        setattr(kb, k, v)
+    await session.commit()
+    await session.refresh(kb)
+    return _to_out(kb)
+
+
+@router.delete("/{kb_id}")
+async def delete_knowledge_base(
+    kb_id: str, session: AsyncSession = Depends(get_session)
+):
+    kb = await session.get(KnowledgeBase, kb_id)
+    if not kb:
+        raise HTTPException(404, "知识库不存在")
+    try:
+        await session.delete(kb)
+        await session.commit()
+    except IntegrityError:
+        # 被助手引用(ON DELETE RESTRICT):先解绑再删
+        await session.rollback()
+        raise HTTPException(409, "知识库正被助手引用,无法删除")
+    return {"ok": True}
diff --git a/backend/schemas.py b/backend/schemas.py
index 69235d6..191a5ed 100644
--- a/backend/schemas.py
+++ b/backend/schemas.py
@@ -7,14 +7,18 @@ JSON 用 camelCase(modelId/interfaceType/apiUrl/apiKey),Python 内部用 snake_c
 
 from __future__ import annotations
 
-from typing import Literal
+from typing import Any, Literal
 
-from pydantic import BaseModel, ConfigDict
+from pydantic import BaseModel, ConfigDict, model_validator
 from pydantic.alias_generators import to_camel
 
 RuntimeMode = Literal["pipeline", "realtime"]
 ModelType = Literal["LLM", "ASR", "TTS", "Realtime", "Embedding"]
 InterfaceType = Literal["openai", "xfyun", "dashscope", "gemini"]
+AssistantType = Literal["prompt", "workflow", "dify", "fastgpt", "opencode"]
+
+# 外部应用类型:其 config.apiKey 是该助手私有密钥,读时打码 / 写时哨兵
+EXTERNAL_TYPES = {"dify", "fastgpt", "opencode"}
 
 
 class CamelModel(BaseModel):
@@ -27,23 +31,86 @@ class CamelModel(BaseModel):
     )
 
 
-# ---------- 助手 ----------
+# ---------- 各类型的 config 形态(JSON 内嵌,按 type 校验) ----------
+class PromptConfig(CamelModel):
+    prompt: str = ""
+    realtime_model: str = ""
+
+
+class WorkflowConfig(CamelModel):
+    graph: dict[str, Any] = {}  # {nodes, edges, viewport};节点 data 可带 *CredentialId 覆盖
+
+
+class DifyConfig(CamelModel):
+    api_url: str = ""
+    api_key: str = ""  # 写时:占位符/空 → 保留旧
+
+
+class FastgptConfig(CamelModel):
+    app_id: str = ""
+    api_url: str = ""
+    api_key: str = ""
+
+
+class OpencodeConfig(CamelModel):
+    prompt: str = ""
+    api_url: str = ""
+    api_key: str = ""
+
+
+CONFIG_BY_TYPE: dict[str, type[CamelModel]] = {
+    "prompt": PromptConfig,
+    "workflow": WorkflowConfig,
+    "dify": DifyConfig,
+    "fastgpt": FastgptConfig,
+    "opencode": OpencodeConfig,
+}
+
+
+# ---------- 助手(单表,无版本化;type 可变) ----------
 class AssistantUpsert(CamelModel):
     name: str
-    greeting: str = ""
-    prompt: str = ""
+    type: AssistantType = "prompt"
     runtime_mode: RuntimeMode = "pipeline"
-    model: str = ""
-    asr: str = ""
-    voice: str = ""
+    greeting: str = ""
     enable_interrupt: bool = True
 
+    # 引用注册资源(FK id;None=未选)
+    llm_credential_id: str | None = None
+    asr_credential_id: str | None = None
+    tts_credential_id: str | None = None
+    realtime_credential_id: str | None = None
+    knowledge_base_id: str | None = None
+
+    # 类型专属字段;校验后归一为 camelCase 存库
+    config: dict[str, Any] = {}
+
+    @model_validator(mode="after")
+    def _normalize_config(self):
+        model = CONFIG_BY_TYPE[self.type]
+        # 按当前 type 校验并裁掉无关字段,统一回 camelCase 落库
+        self.config = model.model_validate(self.config).model_dump(by_alias=True)
+        return self
+
 
 class AssistantOut(AssistantUpsert):
     id: str
     updated_at: str | None = None
 
 
+# ---------- 知识库 ----------
+class KnowledgeBaseUpsert(CamelModel):
+    name: str
+    description: str = ""
+    embedding_credential_id: str | None = None
+
+
+class KnowledgeBaseOut(KnowledgeBaseUpsert):
+    id: str
+    status: str = "active"
+    updated_at: str | None = None
+
+
 # ---------- 模型凭证(对齐前端 ModelResource) ----------
 class CredentialUpsert(CamelModel):
     name: str = ""                              # 资源名称
diff --git a/backend/services/config_resolver.py b/backend/services/config_resolver.py
index bce59c0..e905d89 100644
--- a/backend/services/config_resolver.py
+++ b/backend/services/config_resolver.py
@@ -1,7 +1,7 @@
 """assistant_id → 运行时配置(把真 key 在服务端组装好)。
 
 浏览器只传 assistant_id;真 key 在这里从 provider_credentials 取出注入。
-取不到凭证记录时,降级用 .env 默认值(开发期零配置仍能跑)。
+助手按 FK(*_credential_id)引用凭证;取不到则回退该 type 默认凭证,再回退 .env。
 """
 
 import config
@@ -11,49 +11,57 @@ from sqlalchemy import select
 from sqlalchemy.ext.asyncio import AsyncSession
 
 
-async def _get_credential(
-    session: AsyncSession, type_: str, name: str = ""
+async def _default_credential(
+    session: AsyncSession, type_: str
 ) -> ProviderCredential | None:
-    """取某类(LLM/ASR/TTS)凭证:优先按资源名匹配,否则取该类默认。"""
-    stmt = select(ProviderCredential).where(ProviderCredential.type == type_)
-    if name:
-        # 助手按资源名引用(如 model="DeepSeek-V3");命中则用它
-        named = (
-            await session.execute(stmt.where(ProviderCredential.name == name).limit(1))
-        ).scalar_one_or_none()
-        if named:
-            return named
-    stmt = stmt.order_by(
-        ProviderCredential.is_default.desc(), ProviderCredential.id.asc()
-    ).limit(1)
+    """该 type 的默认凭证(is_default 优先,否则按 id 取第一条)。"""
+    stmt = (
+        select(ProviderCredential)
+        .where(ProviderCredential.type == type_)
+        .order_by(ProviderCredential.is_default.desc(), ProviderCredential.id.asc())
+        .limit(1)
+    )
     return (await session.execute(stmt)).scalar_one_or_none()
 
 
+async def _resolve(
+    session: AsyncSession, cred_id: str | None, type_: str
+) -> ProviderCredential | None:
+    """按 FK id 取凭证;id 为空或失效 → 回退该 type 默认。"""
+    if cred_id:
+        cred = await session.get(ProviderCredential, cred_id)
+        if cred:
+            return cred
+    return await _default_credential(session, type_)
+
+
 async def resolve_runtime_config(
     session: AsyncSession, assistant_id: str
 ) -> AssistantConfig:
-    """加载助手 + 解析凭证,产出可直接交给管线的运行时配置(含真 key)。
-
-    type 映射:LLM→大模型, ASR→语音识别, TTS→语音合成。
-    """
+    """加载助手 + 解析凭证,产出可直接交给管线的运行时配置(含真 key)。"""
     assistant = await session.get(Assistant, assistant_id)
     if assistant is None:
         raise ValueError(f"助手不存在: {assistant_id}")
 
-    llm = await _get_credential(session, "LLM", assistant.model)
-    stt = await _get_credential(session, "ASR", assistant.asr)
-    tts = await _get_credential(session, "TTS")
+    llm = await _resolve(session, assistant.llm_credential_id, "LLM")
+    stt = await _resolve(session, assistant.asr_credential_id, "ASR")
+    tts = await _resolve(session, assistant.tts_credential_id, "TTS")
+    realtime = await _resolve(session, assistant.realtime_credential_id, "Realtime")
+
+    cfg = assistant.config or {}
 
     return AssistantConfig(
         name=assistant.name,
         greeting=assistant.greeting,
-        prompt=assistant.prompt,
+        # 提示词/工作流类型把 prompt 放 config;外部类型由其平台编排,这里给个兜底
+        prompt=cfg.get("prompt") or "你是一个有帮助的助手。",
         runtimeMode=assistant.runtime_mode,  # type: ignore[arg-type]
         enableInterrupt=assistant.enable_interrupt,
-        # 模型/音色:凭证的模型ID优先,否则助手里填的
-        model=(llm.model_id if llm else assistant.model),
-        asr=(stt.model_id if stt else assistant.asr),
-        voice=assistant.voice,
+        # 模型/音色:凭证的模型ID优先
+        model=(llm.model_id if llm else ""),
+        asr=(stt.model_id if stt else ""),
+        voice=cfg.get("voice", ""),  # 音色不再是独立列,若 config 带则用,否则 .env 兜底
+        realtimeModel=(realtime.model_id if realtime else cfg.get("realtimeModel", "")),
         # 运行时连接信息(真 key + url):凭证优先,否则 .env 兜底
         llm_api_key=(llm.api_key if llm else config.LLM_API_KEY),
         llm_base_url=(llm.api_url if llm else config.LLM_BASE_URL),