feat: add MCP search service

.gitignore

@@ -17,6 +17,7 @@ dist
 
 # misc
 .DS_Store
+__pycache__/
 *.pem
 npm-debug.log*
 yarn-debug.log*

docker/docker-compose.yaml

@@ -213,28 +213,30 @@ services:
       - dev_local_backend
       - prod
 
-  mcp-server:
+  mcp-service:
     build:
       context: ..
-      dockerfile: docker/mcp-service.Dockerfile
+      dockerfile: mcp/Dockerfile
     container_name: ${COMPOSE_PROJECT_NAME}-openisle-mcp
     env_file:
       - ${ENV_FILE:-../.env}
     environment:
-      OPENISLE_API_BASE_URL: ${OPENISLE_API_BASE_URL:-http://springboot:8080}
-      OPENISLE_MCP_HOST: ${OPENISLE_MCP_HOST:-0.0.0.0}
-      OPENISLE_MCP_PORT: ${OPENISLE_MCP_PORT:-8000}
-      OPENISLE_MCP_TRANSPORT: ${OPENISLE_MCP_TRANSPORT:-streamable-http}
+      FASTMCP_HOST: 0.0.0.0
+      FASTMCP_PORT: ${MCP_PORT:-8765}
+      OPENISLE_BACKEND_URL: ${OPENISLE_BACKEND_URL:-http://springboot:8080}
+      OPENISLE_BACKEND_TIMEOUT: ${OPENISLE_BACKEND_TIMEOUT:-10}
+      OPENISLE_MCP_TRANSPORT: ${OPENISLE_MCP_TRANSPORT:-sse}
+      OPENISLE_MCP_SSE_MOUNT_PATH: ${OPENISLE_MCP_SSE_MOUNT_PATH:-/mcp}
     ports:
-      - "${OPENISLE_MCP_PORT:-8000}:8000"
+      - "${MCP_PORT:-8765}:${MCP_PORT:-8765}"
     depends_on:
       springboot:
         condition: service_healthy
+    restart: unless-stopped
     networks:
       - openisle-network
     profiles:
       - dev
-      - dev_local_backend
       - prod
 
   frontend_dev:

docker/mcp-service.Dockerfile

@@ -1,20 +0,0 @@
-FROM python:3.11-slim AS base
-
-ENV PYTHONUNBUFFERED=1 \
-    PIP_NO_CACHE_DIR=1
-
-WORKDIR /app
-
-COPY mcp/pyproject.toml mcp/README.md ./
-COPY mcp/src ./src
-RUN pip install --upgrade pip \
-    && pip install .
-
-EXPOSE 8000
-
-ENV OPENISLE_API_BASE_URL=http://springboot:8080 \
-    OPENISLE_MCP_HOST=0.0.0.0 \
-    OPENISLE_MCP_PORT=8000 \
-    OPENISLE_MCP_TRANSPORT=streamable-http
-
-CMD ["openisle-mcp"]

mcp/.gitignore

@@ -1,6 +0,0 @@
-__pycache__/
-*.py[cod]
-*.egg-info/
-.build/
-.venv/
-.env

mcp/Dockerfile

@@ -0,0 +1,17 @@
+FROM python:3.11-slim AS runtime
+
+ENV PYTHONUNBUFFERED=1 \
+    PIP_NO_CACHE_DIR=1
+
+WORKDIR /app
+
+COPY mcp/pyproject.toml /app/pyproject.toml
+COPY mcp/README.md /app/README.md
+COPY mcp/src /app/src
+
+RUN pip install --upgrade pip \
+    && pip install .
+
+EXPOSE 8765
+
+CMD ["openisle-mcp"]

mcp/README.md

@@ -1,45 +1,39 @@
 # OpenIsle MCP Server
 
-This package exposes a [Model Context Protocol](https://github.com/modelcontextprotocol) (MCP) server for OpenIsle.
-The initial release focuses on surfacing the platform's search capabilities so that AI assistants can discover
-users and posts directly through the existing REST API. Future iterations can expand this service with post
-creation and other productivity tools.
+This package provides a [Model Context Protocol](https://github.com/modelcontextprotocol) (MCP) server that exposes the OpenIsle
+search capabilities to AI assistants. The server wraps the existing Spring Boot backend and currently provides a single `search`
+tool. Future iterations can extend the server with additional functionality such as publishing new posts or moderating content.
 
 ## Features
 
-- 🔍 Keyword search across users and posts using the OpenIsle backend APIs
-- ✅ Structured MCP tool response for downstream reasoning
-- 🩺 Lightweight health check endpoint (`/health`) for container orchestration
-- ⚙️ Configurable via environment variables with sensible defaults for Docker Compose
+- 🔍 **Global search** — delegates to the existing `/api/search/global` endpoint exposed by the OpenIsle backend.
+- 🧠 **Structured results** — responses include highlights and deep links so AI clients can present the results cleanly.
+- ⚙️ **Configurable** — point the server at any reachable OpenIsle backend by setting environment variables.
 
-## Running locally
+## Local development
 
 ```bash
 cd mcp
-pip install .
-openisle-mcp  # starts the MCP server on http://127.0.0.1:8000 by default
+python -m venv .venv
+source .venv/bin/activate
+pip install -e .
+openisle-mcp --transport stdio  # or "sse"/"streamable-http"
 ```
 
-By default the server targets `http://localhost:8080` for backend requests. Override the target by setting
-`OPENISLE_API_BASE_URL` before starting the service.
+Environment variables:
 
-## Environment variables
-
-| Variable | Default | Description |
-| -------- | ------- | ----------- |
-| `OPENISLE_API_BASE_URL` | `http://localhost:8080` | Base URL of the OpenIsle backend API |
-| `OPENISLE_MCP_HOST` | `127.0.0.1` | Hostname/interface for the MCP HTTP server |
-| `OPENISLE_MCP_PORT` | `8000` | Port for the MCP HTTP server |
-| `OPENISLE_MCP_TRANSPORT` | `streamable-http` | Transport mode (`stdio`, `sse`, or `streamable-http`) |
-| `OPENISLE_MCP_TIMEOUT_SECONDS` | `10` | HTTP timeout when calling the backend |
+| Variable | Description | Default |
+| --- | --- | --- |
+| `OPENISLE_BACKEND_URL` | Base URL of the Spring Boot backend | `http://springboot:8080` |
+| `OPENISLE_BACKEND_TIMEOUT` | Timeout (seconds) for backend HTTP calls | `10` |
+| `OPENISLE_PUBLIC_BASE_URL` | Optional base URL used to build deep links in search results | *(unset)* |
+| `OPENISLE_MCP_TRANSPORT` | MCP transport (`stdio`, `sse`, `streamable-http`) | `stdio` |
+| `OPENISLE_MCP_SSE_MOUNT_PATH` | Mount path when using SSE transport | `/mcp` |
+| `FASTMCP_HOST` | Host for SSE / HTTP transports | `127.0.0.1` |
+| `FASTMCP_PORT` | Port for SSE / HTTP transports | `8000` |
 
 ## Docker
 
-The repository's Docker Compose stack now includes the MCP server. To start it alongside other services:
+A dedicated Docker image is provided and wired into `docker-compose.yaml`. The container listens on
+`${MCP_PORT:-8765}` and connects to the backend service running in the same compose stack.
 
-```bash
-cd docker
-docker compose --profile dev up mcp-server
-```
-
-The service exposes port `8000` by default. Update `OPENISLE_MCP_PORT` to customize the mapped port.

mcp/pyproject.toml

@@ -5,22 +5,23 @@ build-backend = "setuptools.build_meta"
 [project]
 name = "openisle-mcp"
 version = "0.1.0"
-description = "Model Context Protocol server exposing OpenIsle search capabilities."
+description = "Model Context Protocol server exposing OpenIsle search capabilities"
 readme = "README.md"
+authors = [{name = "OpenIsle Team"}]
+license = {text = "MIT"}
 requires-python = ">=3.11"
-authors = [{ name = "OpenIsle" }]
 dependencies = [
   "mcp>=1.19.0",
-  "httpx>=0.28.1",
-  "pydantic>=2.7.0"
+  "httpx>=0.28.0",
+  "pydantic>=2.12.0",
 ]
 
-[project.urls]
-Homepage = "https://github.com/openisle/openisle"
-
 [project.scripts]
 openisle-mcp = "openisle_mcp.server:main"
 
+[tool.setuptools]
+package-dir = {"" = "src"}
+
 [tool.setuptools.packages.find]
 where = ["src"]
 

mcp/src/openisle_mcp/__init__.py

@@ -1,14 +1,10 @@
 """OpenIsle MCP server package."""
 
-from .config import Settings, get_settings
-from .models import SearchItem, SearchResponse, SearchScope
+from importlib import metadata
 
-__all__ = [
-    "Settings",
-    "get_settings",
-    "SearchItem",
-    "SearchResponse",
-    "SearchScope",
-]
+try:
+    __version__ = metadata.version("openisle-mcp")
+except metadata.PackageNotFoundError:  # pragma: no cover - best effort during dev
+    __version__ = "0.0.0"
 
-__version__ = "0.1.0"
+__all__ = ["__version__"]

mcp/src/openisle_mcp/client.py

@@ -1,33 +1,79 @@
-"""HTTP client helpers for interacting with the OpenIsle backend APIs."""
+"""HTTP client for talking to the OpenIsle backend."""
 
 from __future__ import annotations
 
-from typing import Any
+import json
+import logging
+from typing import List
 
 import httpx
+from pydantic import ValidationError
 
-from .config import Settings, get_settings
-from .models import SearchScope
+from .models import BackendSearchResult
+
+__all__ = ["BackendClientError", "OpenIsleBackendClient"]
+
+logger = logging.getLogger(__name__)
 
 
-class OpenIsleAPI:
-    """Thin wrapper around the OpenIsle REST API used by the MCP server."""
+class BackendClientError(RuntimeError):
+    """Raised when the backend cannot fulfil a request."""
 
-    def __init__(self, settings: Settings | None = None) -> None:
-        self._settings = settings or get_settings()
 
-    async def search(self, scope: SearchScope, keyword: str) -> list[Any]:
-        """Execute a search request against the backend API."""
+class OpenIsleBackendClient:
+    """Tiny wrapper around the Spring Boot search endpoints."""
 
-        url_path = self._settings.get_search_path(scope)
-        async with httpx.AsyncClient(
-            base_url=str(self._settings.backend_base_url),
-            timeout=self._settings.request_timeout_seconds,
-        ) as client:
-            response = await client.get(url_path, params={"keyword": keyword})
-            response.raise_for_status()
-            data = response.json()
+    def __init__(self, base_url: str, timeout: float = 10.0) -> None:
+        if not base_url:
+            raise ValueError("base_url must not be empty")
+        self._base_url = base_url.rstrip("/")
+        timeout = timeout if timeout > 0 else 10.0
+        self._timeout = httpx.Timeout(timeout, connect=timeout, read=timeout)
 
-        if not isinstance(data, list):
-            raise RuntimeError("Unexpected search response payload: expected a list")
-        return data
+    @property
+    def base_url(self) -> str:
+        return self._base_url
+
+    async def search_global(self, keyword: str) -> List[BackendSearchResult]:
+        """Call `/api/search/global` and normalise the payload."""
+
+        url = f"{self._base_url}/api/search/global"
+        params = {"keyword": keyword}
+        headers = {"Accept": "application/json"}
+        logger.debug("Calling OpenIsle backend", extra={"url": url, "params": params})
+
+        try:
+            async with httpx.AsyncClient(timeout=self._timeout, headers=headers, follow_redirects=True) as client:
+                response = await client.get(url, params=params)
+                response.raise_for_status()
+        except httpx.HTTPStatusError as exc:  # pragma: no cover - network errors are rare in tests
+            body_preview = _truncate_body(exc.response.text)
+            raise BackendClientError(
+                f"Backend returned HTTP {exc.response.status_code}: {body_preview}"
+            ) from exc
+        except httpx.RequestError as exc:  # pragma: no cover - network errors are rare in tests
+            raise BackendClientError(f"Failed to reach backend: {exc}") from exc
+
+        try:
+            payload = response.json()
+        except json.JSONDecodeError as exc:
+            raise BackendClientError("Backend returned invalid JSON") from exc
+
+        if not isinstance(payload, list):
+            raise BackendClientError("Unexpected search payload type; expected a list")
+
+        results: list[BackendSearchResult] = []
+        for item in payload:
+            try:
+                results.append(BackendSearchResult.model_validate(item))
+            except ValidationError as exc:
+                raise BackendClientError(f"Invalid search result payload: {exc}") from exc
+
+        return results
+
+
+def _truncate_body(body: str, limit: int = 200) -> str:
+    body = body.strip()
+    if len(body) <= limit:
+        return body
+    return f"{body[:limit]}…"

mcp/src/openisle_mcp/config.py

@@ -1,83 +0,0 @@
-"""Configuration helpers for the OpenIsle MCP server."""
-
-from __future__ import annotations
-
-import os
-from functools import lru_cache
-from typing import Dict, Literal
-
-from pydantic import AnyHttpUrl, BaseModel, Field, ValidationError
-
-from .models import SearchScope
-
-TransportType = Literal["stdio", "sse", "streamable-http"]
-
-
-class Settings(BaseModel):
-    """Runtime configuration for the MCP server."""
-
-    backend_base_url: AnyHttpUrl = Field(
-        default="http://localhost:8080",
-        description="Base URL of the OpenIsle backend API.",
-    )
-    request_timeout_seconds: float = Field(
-        default=10.0,
-        gt=0,
-        description="HTTP timeout when talking to the backend APIs.",
-    )
-    transport: TransportType = Field(
-        default="streamable-http",
-        description="Transport mode for the MCP server.",
-    )
-    host: str = Field(default="127.0.0.1", description="Hostname/interface used by the MCP HTTP server.")
-    port: int = Field(default=8000, ge=0, description="Port used by the MCP HTTP server.")
-    search_paths: Dict[str, str] = Field(
-        default_factory=lambda: {
-            SearchScope.GLOBAL.value: "/api/search/global",
-            SearchScope.USERS.value: "/api/search/users",
-            SearchScope.POSTS.value: "/api/search/posts",
-            SearchScope.POSTS_TITLE.value: "/api/search/posts/title",
-            SearchScope.POSTS_CONTENT.value: "/api/search/posts/content",
-        },
-        description="Mapping between search scopes and backend API paths.",
-    )
-
-    def get_search_path(self, scope: SearchScope) -> str:
-        """Return the backend path associated with a given search scope."""
-
-        try:
-            return self.search_paths[scope.value]
-        except KeyError as exc:  # pragma: no cover - defensive guard
-            raise ValueError(f"Unsupported search scope: {scope}") from exc
-
-
-@lru_cache(maxsize=1)
-def get_settings() -> Settings:
-    """Load settings from environment variables with caching."""
-
-    raw_settings: Dict[str, object] = {}
-
-    backend_url = os.getenv("OPENISLE_API_BASE_URL")
-    if backend_url:
-        raw_settings["backend_base_url"] = backend_url
-
-    timeout = os.getenv("OPENISLE_MCP_TIMEOUT_SECONDS")
-    if timeout:
-        raw_settings["request_timeout_seconds"] = float(timeout)
-
-    transport = os.getenv("OPENISLE_MCP_TRANSPORT")
-    if transport:
-        raw_settings["transport"] = transport
-
-    host = os.getenv("OPENISLE_MCP_HOST")
-    if host:
-        raw_settings["host"] = host
-
-    port = os.getenv("OPENISLE_MCP_PORT")
-    if port:
-        raw_settings["port"] = int(port)
-
-    try:
-        return Settings(**raw_settings)
-    except (ValidationError, ValueError) as exc:  # pragma: no cover - configuration errors should surface clearly
-        raise RuntimeError(f"Invalid MCP configuration: {exc}") from exc

mcp/src/openisle_mcp/models.py

@@ -1,45 +1,58 @@
-"""Data models for the OpenIsle MCP server."""
+"""Pydantic models used by the OpenIsle MCP server."""
 
 from __future__ import annotations
 
-from enum import Enum
-from typing import Any, Dict, Optional
+from typing import Dict, Optional
 
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, ConfigDict, Field
+
+__all__ = [
+    "BackendSearchResult",
+    "SearchResult",
+    "SearchResponse",
+]
 
 
-class SearchScope(str, Enum):
-    """Supported search scopes exposed via the MCP tool."""
+class BackendSearchResult(BaseModel):
+    """Shape of the payload returned by the OpenIsle backend."""
 
-    GLOBAL = "global"
-    USERS = "users"
-    POSTS = "posts"
-    POSTS_TITLE = "posts_title"
-    POSTS_CONTENT = "posts_content"
+    type: str
+    id: Optional[int] = None
+    text: Optional[str] = None
+    sub_text: Optional[str] = Field(default=None, alias="subText")
+    extra: Optional[str] = None
+    post_id: Optional[int] = Field(default=None, alias="postId")
+    highlighted_text: Optional[str] = Field(default=None, alias="highlightedText")
+    highlighted_sub_text: Optional[str] = Field(default=None, alias="highlightedSubText")
+    highlighted_extra: Optional[str] = Field(default=None, alias="highlightedExtra")
+
+    model_config = ConfigDict(populate_by_name=True, extra="ignore")
 
 
-class Highlight(BaseModel):
-    """Highlighted fragments returned by the backend search API."""
+class SearchResult(BaseModel):
+    """Structured search result returned to MCP clients."""
 
-    text: Optional[str] = Field(default=None, description="Highlighted main text snippet.")
-    sub_text: Optional[str] = Field(default=None, description="Highlighted secondary text snippet.")
-    extra: Optional[str] = Field(default=None, description="Additional highlighted data.")
+    type: str = Field(description="Entity type, e.g. post, comment, user")
+    id: Optional[int] = Field(default=None, description="Primary identifier for the entity")
+    title: Optional[str] = Field(default=None, description="Primary text to display")
+    subtitle: Optional[str] = Field(default=None, description="Secondary text (e.g. author or category)")
+    extra: Optional[str] = Field(default=None, description="Additional descriptive snippet")
+    post_id: Optional[int] = Field(default=None, description="Associated post id for comment results")
+    url: Optional[str] = Field(default=None, description="Deep link to the resource inside OpenIsle")
+    highlights: Dict[str, Optional[str]] = Field(
+        default_factory=dict,
+        description="Highlighted HTML fragments keyed by field name",
+    )
 
-
-class SearchItem(BaseModel):
-    """Normalized representation of a single search result."""
-
-    category: str = Field(description="Type/category of the search result, e.g. user or post.")
-    title: Optional[str] = Field(default=None, description="Primary title or label for the result.")
-    description: Optional[str] = Field(default=None, description="Supporting description or summary text.")
-    url: Optional[str] = Field(default=None, description="Canonical URL that references the resource, if available.")
-    metadata: Dict[str, Any] = Field(default_factory=dict, description="Additional structured metadata extracted from the API.")
-    highlights: Optional[Highlight] = Field(default=None, description="Highlighted snippets returned by the backend search API.")
+    model_config = ConfigDict(populate_by_name=True)
 
 
 class SearchResponse(BaseModel):
-    """Structured response returned by the MCP search tool."""
+    """Response envelope returned from the MCP search tool."""
 
-    scope: SearchScope = Field(description="Scope of the search that produced the results.")
-    keyword: str = Field(description="Keyword submitted to the backend search endpoint.")
-    results: list[SearchItem] = Field(default_factory=list, description="Normalized search results from the backend API.")
+    keyword: str = Field(description="Sanitised keyword that was searched for")
+    total_results: int = Field(description="Total number of results returned by the backend")
+    limit: int = Field(description="Maximum number of results included in the response")
+    results: list[SearchResult] = Field(default_factory=list, description="Search results up to the requested limit")
+
+    model_config = ConfigDict(populate_by_name=True)

mcp/src/openisle_mcp/search.py

@@ -1,100 +0,0 @@
-"""Utilities for normalising OpenIsle search results."""
-
-from __future__ import annotations
-
-import re
-from typing import Any, Iterable
-
-from .models import Highlight, SearchItem, SearchScope
-
-
-def _truncate(text: str | None, *, limit: int = 240) -> str | None:
-    """Compress whitespace and truncate overly long text fragments."""
-
-    if not text:
-        return None
-    compact = re.sub(r"\s+", " ", text).strip()
-    if len(compact) <= limit:
-        return compact
-    return f"{compact[:limit - 1]}…"
-
-
-def _extract_highlight(data: dict[str, Any]) -> Highlight | None:
-    highlighted = {
-        "text": data.get("highlightedText"),
-        "sub_text": data.get("highlightedSubText"),
-        "extra": data.get("highlightedExtra"),
-    }
-    if any(highlighted.values()):
-        return Highlight(**highlighted)
-    return None
-
-
-def normalise_results(scope: SearchScope, payload: Iterable[dict[str, Any]]) -> list[SearchItem]:
-    """Convert backend payloads into :class:`SearchItem` entries."""
-
-    normalised: list[SearchItem] = []
-
-    for item in payload:
-        if not isinstance(item, dict):
-            continue
-
-        if scope is SearchScope.GLOBAL:
-            normalised.append(
-                SearchItem(
-                    category=item.get("type", scope.value),
-                    title=_truncate(item.get("text")),
-                    description=_truncate(item.get("subText")),
-                    metadata={
-                        "id": item.get("id"),
-                        "postId": item.get("postId"),
-                        "extra": item.get("extra"),
-                    },
-                    highlights=_extract_highlight(item),
-                )
-            )
-            continue
-
-        if scope in {SearchScope.POSTS, SearchScope.POSTS_CONTENT, SearchScope.POSTS_TITLE}:
-            author = item.get("author") or {}
-            category = item.get("category") or {}
-            metadata = {
-                "id": item.get("id"),
-                "author": author.get("username"),
-                "category": category.get("name"),
-                "views": item.get("views"),
-                "commentCount": item.get("commentCount"),
-                "tags": [tag.get("name") for tag in item.get("tags", []) if isinstance(tag, dict)],
-            }
-            normalised.append(
-                SearchItem(
-                    category="post",
-                    title=_truncate(item.get("title")),
-                    description=_truncate(item.get("content")),
-                    metadata={k: v for k, v in metadata.items() if v is not None},
-                )
-            )
-            continue
-
-        if scope is SearchScope.USERS:
-            metadata = {
-                "id": item.get("id"),
-                "email": item.get("email"),
-                "followers": item.get("followers"),
-                "following": item.get("following"),
-                "role": item.get("role"),
-            }
-            normalised.append(
-                SearchItem(
-                    category="user",
-                    title=_truncate(item.get("username")),
-                    description=_truncate(item.get("introduction")),
-                    metadata={k: v for k, v in metadata.items() if v is not None},
-                )
-            )
-            continue
-
-        # Fallback: include raw entry to aid debugging of unsupported scopes
-        normalised.append(SearchItem(category=scope.value, metadata=item))
-
-    return normalised

mcp/src/openisle_mcp/server.py

@@ -2,120 +2,163 @@
 
 from __future__ import annotations
 
+import argparse
 import logging
 import os
-from typing import Annotated
+from typing import Annotated, Optional
 
 from mcp.server.fastmcp import Context, FastMCP
-from mcp.server.fastmcp.logging import configure_logging
+from mcp.server.fastmcp import exceptions as mcp_exceptions
 from pydantic import Field
-from starlette.requests import Request
-from starlette.responses import JSONResponse, Response
 
-from .client import OpenIsleAPI
-from .config import Settings, get_settings
-from .models import SearchResponse, SearchScope
-from .search import normalise_results
+from .client import BackendClientError, OpenIsleBackendClient
+from .models import BackendSearchResult, SearchResponse, SearchResult
 
-_logger = logging.getLogger(__name__)
+logger = logging.getLogger(__name__)
+
+APP_NAME = "openisle-mcp"
+DEFAULT_BACKEND_URL = "http://springboot:8080"
+DEFAULT_TRANSPORT = "stdio"
+DEFAULT_TIMEOUT = 10.0
+DEFAULT_LIMIT = 20
+MAX_LIMIT = 50
+
+server = FastMCP(
+    APP_NAME,
+    instructions=(
+        "Use the `search` tool to query OpenIsle content. "
+        "Results include posts, comments, users, categories, and tags."
+    ),
+)
 
 
-def _create_server(settings: Settings) -> FastMCP:
-    """Instantiate the FastMCP server with configured metadata."""
+def _env(name: str, default: Optional[str] = None) -> Optional[str]:
+    value = os.getenv(name, default)
+    if value is None:
+        return None
+    trimmed = value.strip()
+    return trimmed or default
 
-    server = FastMCP(
-        name="OpenIsle MCP",
-        instructions=(
-            "Access OpenIsle search functionality. Provide a keyword and optionally a scope to "
-            "discover users and posts from the community."
-        ),
-        host=settings.host,
-        port=settings.port,
-        transport_security=None,
+
+def _load_timeout() -> float:
+    raw = _env("OPENISLE_BACKEND_TIMEOUT", str(DEFAULT_TIMEOUT))
+    try:
+        timeout = float(raw) if raw is not None else DEFAULT_TIMEOUT
+    except ValueError:
+        logger.warning("Invalid OPENISLE_BACKEND_TIMEOUT value '%s', falling back to %s", raw, DEFAULT_TIMEOUT)
+        return DEFAULT_TIMEOUT
+    if timeout <= 0:
+        logger.warning("Non-positive OPENISLE_BACKEND_TIMEOUT %s, falling back to %s", timeout, DEFAULT_TIMEOUT)
+        return DEFAULT_TIMEOUT
+    return timeout
+
+
+_BACKEND_CLIENT = OpenIsleBackendClient(
+    base_url=_env("OPENISLE_BACKEND_URL", DEFAULT_BACKEND_URL) or DEFAULT_BACKEND_URL,
+    timeout=_load_timeout(),
+)
+_PUBLIC_BASE_URL = _env("OPENISLE_PUBLIC_BASE_URL")
+
+
+def _build_url(result: BackendSearchResult) -> Optional[str]:
+    if not _PUBLIC_BASE_URL:
+        return None
+    base = _PUBLIC_BASE_URL.rstrip("/")
+    if result.type in {"post", "post_title"} and result.id is not None:
+        return f"{base}/posts/{result.id}"
+    if result.type == "comment" and result.post_id is not None:
+        anchor = f"#comment-{result.id}" if result.id is not None else ""
+        return f"{base}/posts/{result.post_id}{anchor}"
+    if result.type == "user" and result.id is not None:
+        return f"{base}/users/{result.id}"
+    if result.type == "category" and result.id is not None:
+        return f"{base}/?categoryId={result.id}"
+    if result.type == "tag" and result.id is not None:
+        return f"{base}/?tagIds={result.id}"
+    return None
+
+
+def _to_search_result(result: BackendSearchResult) -> SearchResult:
+    highlights = {
+        "text": result.highlighted_text,
+        "subText": result.highlighted_sub_text,
+        "extra": result.highlighted_extra,
+    }
+    # Remove empty highlight entries to keep the payload clean
+    highlights = {key: value for key, value in highlights.items() if value}
+    return SearchResult(
+        type=result.type,
+        id=result.id,
+        title=result.text,
+        subtitle=result.sub_text,
+        extra=result.extra,
+        post_id=result.post_id,
+        url=_build_url(result),
+        highlights=highlights,
     )
 
-    @server.custom_route("/health", methods=["GET"])
-    async def health(_: Request) -> Response:  # pragma: no cover - exercised via runtime checks
-        return JSONResponse({"status": "ok"})
 
-    return server
+KeywordParam = Annotated[str, Field(description="Keyword to search for", min_length=1)]
+LimitParam = Annotated[
+    int,
+    Field(ge=1, le=MAX_LIMIT, description=f"Maximum number of results to return (<= {MAX_LIMIT})"),
+]
 
 
-async def _execute_search(
-    *,
-    api: OpenIsleAPI,
-    scope: SearchScope,
-    keyword: str,
-    context: Context | None,
-) -> SearchResponse:
-    message = f"Searching OpenIsle scope={scope.value} keyword={keyword!r}"
-    if context is not None:
-        context.info(message)
-    else:
-        _logger.info(message)
+@server.tool(name="search", description="Search OpenIsle content")
+async def search(keyword: KeywordParam, limit: LimitParam = DEFAULT_LIMIT, ctx: Optional[Context] = None) -> SearchResponse:
+    """Run a search query against the OpenIsle backend."""
 
-    payload = await api.search(scope, keyword)
-    items = normalise_results(scope, payload)
-    return SearchResponse(scope=scope, keyword=keyword, results=items)
+    trimmed = keyword.strip()
+    if not trimmed:
+        raise mcp_exceptions.ToolError("Keyword must not be empty")
 
+    if ctx is not None:
+        await ctx.debug(f"Searching OpenIsle for '{trimmed}' (limit={limit})")
 
-def build_server(settings: Settings | None = None) -> FastMCP:
-    """Configure and return the FastMCP server instance."""
+    try:
+        raw_results = await _BACKEND_CLIENT.search_global(trimmed)
+    except BackendClientError as exc:
+        if ctx is not None:
+            await ctx.error(f"Search request failed: {exc}")
+        raise mcp_exceptions.ToolError(f"Search failed: {exc}") from exc
 
-    resolved_settings = settings or get_settings()
-    server = _create_server(resolved_settings)
-    api_client = OpenIsleAPI(resolved_settings)
+    results = [_to_search_result(result) for result in raw_results]
+    limited = results[:limit]
 
-    @server.tool(
-        name="openisle_search",
-        description="Search OpenIsle for users and posts.",
-    )
-    async def openisle_search(
-        keyword: Annotated[str, Field(description="Keyword used to query OpenIsle search.")],
-        scope: Annotated[
-            SearchScope,
-            Field(
-                description=(
-                    "Scope of the search. Use 'global' to search across users and posts, or specify "
-                    "'users', 'posts', 'posts_title', or 'posts_content' to narrow the results."
-                )
-            ),
-        ] = SearchScope.GLOBAL,
-        context: Context | None = None,
-    ) -> SearchResponse:
-        try:
-            return await _execute_search(api=api_client, scope=scope, keyword=keyword, context=context)
-        except Exception as exc:  # pragma: no cover - surfaced to the MCP runtime
-            error_message = f"Search failed: {exc}"
-            if context is not None:
-                context.error(error_message)
-            _logger.exception("Search tool failed")
-            raise
+    if ctx is not None:
+        await ctx.info(
+            "Search completed",
+            keyword=trimmed,
+            total_results=len(results),
+            returned=len(limited),
+        )
 
-    return server
+    return SearchResponse(keyword=trimmed, total_results=len(results), limit=limit, results=limited)
 
 
 def main() -> None:
-    """CLI entry point used by the console script."""
+    parser = argparse.ArgumentParser(description="Run the OpenIsle MCP server")
+    parser.add_argument(
+        "--transport",
+        choices=["stdio", "sse", "streamable-http"],
+        default=_env("OPENISLE_MCP_TRANSPORT", DEFAULT_TRANSPORT),
+        help="Transport protocol to use",
+    )
+    parser.add_argument(
+        "--mount-path",
+        default=_env("OPENISLE_MCP_SSE_MOUNT_PATH", "/mcp"),
+        help="Mount path when using the SSE transport",
+    )
+    args = parser.parse_args()
 
-    settings = get_settings()
-    configure_logging("INFO")
-    server = build_server(settings)
+    logging.basicConfig(level=os.getenv("OPENISLE_MCP_LOG_LEVEL", "INFO"))
+    logger.info(
+        "Starting OpenIsle MCP server", extra={"transport": args.transport, "backend": _BACKEND_CLIENT.base_url}
+    )
 
-    transport = os.getenv("OPENISLE_MCP_TRANSPORT", settings.transport)
-    if transport not in {"stdio", "sse", "streamable-http"}:
-        raise RuntimeError(f"Unsupported transport mode: {transport}")
-
-    _logger.info("Starting OpenIsle MCP server on %s:%s via %s", settings.host, settings.port, transport)
-
-    if transport == "stdio":
-        server.run("stdio")
-    elif transport == "sse":
-        mount_path = os.getenv("OPENISLE_MCP_SSE_PATH")
-        server.run("sse", mount_path=mount_path)
-    else:
-        server.run("streamable-http")
+    server.run(transport=args.transport, mount_path=args.mount_path)
 
 
-if __name__ == "__main__":  # pragma: no cover - manual execution path
+if __name__ == "__main__":
     main()