chore: more linting (#261)

A bit more linting for line length

Author: eyurtsev

Makefile

@@ -31,8 +31,8 @@ lint lint_diff:
 	# [ "$(PYTHON_FILES)" = "" ] || uv run mypy $(PYTHON_FILES)
 
 format format_diff:
-	[ "$(PYTHON_FILES)" = "" ] || uv run ruff check --fix $(PYTHON_FILES)
 	[ "$(PYTHON_FILES)" = "" ] || uv run ruff format $(PYTHON_FILES)
+	[ "$(PYTHON_FILES)" = "" ] || uv run ruff check --fix $(PYTHON_FILES)
 
 
 

langchain_mcp_adapters/client.py

@@ -1,4 +1,4 @@
-"""Client for connecting to multiple MCP servers and loading LangChain-compatible resources.
+"""Client for connecting to multiple MCP servers and loading LangChain tools/resources.
 
 This module provides the MultiServerMCPClient class for managing connections to multiple
 MCP servers and loading tools, prompts, and resources from them.
@@ -29,7 +29,8 @@
 from langchain_mcp_adapters.tools import load_mcp_tools
 
 ASYNC_CONTEXT_MANAGER_ERROR = (
-    "As of langchain-mcp-adapters 0.1.0, MultiServerMCPClient cannot be used as a context manager (e.g., async with MultiServerMCPClient(...)). "
+    "As of langchain-mcp-adapters 0.1.0, MultiServerMCPClient cannot be used as a "
+    "context manager (e.g., async with MultiServerMCPClient(...)). "
     "Instead, you can do one of the following:\n"
     "1. client = MultiServerMCPClient(...)\n"
     "   tools = await client.get_tools()\n"
@@ -40,7 +41,10 @@
 
 
 class MultiServerMCPClient:
-    """Client for connecting to multiple MCP servers and loading LangChain-compatible tools, prompts and resources from them."""
+    """Client for connecting to multiple MCP servers.
+
+    Loads LangChain-compatible tools, prompts and resources from MCP servers.
+    """
 
     def __init__(self, connections: dict[str, Connection] | None = None) -> None:
         """Initialize a MultiServerMCPClient with MCP servers connections.
@@ -58,7 +62,8 @@ def __init__(self, connections: dict[str, Connection] | None = None) -> None:
             {
                 "math": {
                     "command": "python",
-                    # Make sure to update to the full absolute path to your math_server.py file
+                    # Make sure to update to the full absolute path to your
+                    # math_server.py file
                     "args": ["/path/to/math_server.py"],
                     "transport": "stdio",
                 },
@@ -84,7 +89,9 @@ def __init__(self, connections: dict[str, Connection] | None = None) -> None:
         ```
 
         """
-        self.connections: dict[str, Connection] = connections if connections is not None else {}
+        self.connections: dict[str, Connection] = (
+            connections if connections is not None else {}
+        )
 
     @asynccontextmanager
     async def session(
@@ -107,7 +114,10 @@ async def session(
 
         """
         if server_name not in self.connections:
-            msg = f"Couldn't find a server with name '{server_name}', expected one of '{list(self.connections.keys())}'"
+            msg = (
+                f"Couldn't find a server with name '{server_name}', "
+                f"expected one of '{list(self.connections.keys())}'"
+            )
             raise ValueError(msg)
 
         async with create_session(self.connections[server_name]) as session:
@@ -130,14 +140,19 @@ async def get_tools(self, *, server_name: str | None = None) -> list[BaseTool]:
         """
         if server_name is not None:
             if server_name not in self.connections:
-                msg = f"Couldn't find a server with name '{server_name}', expected one of '{list(self.connections.keys())}'"
+                msg = (
+                    f"Couldn't find a server with name '{server_name}', "
+                    f"expected one of '{list(self.connections.keys())}'"
+                )
                 raise ValueError(msg)
             return await load_mcp_tools(None, connection=self.connections[server_name])
 
         all_tools: list[BaseTool] = []
         load_mcp_tool_tasks = []
         for connection in self.connections.values():
-            load_mcp_tool_task = asyncio.create_task(load_mcp_tools(None, connection=connection))
+            load_mcp_tool_task = asyncio.create_task(
+                load_mcp_tools(None, connection=connection)
+            )
             load_mcp_tool_tasks.append(load_mcp_tool_task)
         tools_list = await asyncio.gather(*load_mcp_tool_tasks)
         for tools in tools_list:
@@ -165,7 +180,8 @@ async def get_resources(
 
         Args:
             server_name: Name of the server to get resources from
-            uris: Optional resource URI or list of URIs to load. If not provided, all resources will be loaded.
+            uris: Optional resource URI or list of URIs to load. If not provided,
+                all resources will be loaded.
 
         Returns:
             A list of LangChain Blobs

langchain_mcp_adapters/prompts.py

@@ -53,5 +53,6 @@ async def load_mcp_prompt(
     """
     response = await session.get_prompt(name, arguments)
     return [
-        convert_mcp_prompt_message_to_langchain_message(message) for message in response.messages
+        convert_mcp_prompt_message_to_langchain_message(message)
+        for message in response.messages
     ]

langchain_mcp_adapters/resources.py

@@ -11,7 +11,9 @@
 from mcp.types import BlobResourceContents, ResourceContents, TextResourceContents
 
 
-def convert_mcp_resource_to_langchain_blob(resource_uri: str, contents: ResourceContents) -> Blob:
+def convert_mcp_resource_to_langchain_blob(
+    resource_uri: str, contents: ResourceContents
+) -> Blob:
     """Convert an MCP resource content to a LangChain Blob.
 
     Args:
@@ -30,7 +32,9 @@ def convert_mcp_resource_to_langchain_blob(resource_uri: str, contents: Resource
         msg = f"Unsupported content type for URI {resource_uri}"
         raise TypeError(msg)
 
-    return Blob.from_data(data=data, mime_type=contents.mimeType, metadata={"uri": resource_uri})
+    return Blob.from_data(
+        data=data, mime_type=contents.mimeType, metadata={"uri": resource_uri}
+    )
 
 
 async def get_mcp_resource(session: ClientSession, uri: str) -> list[Blob]:
@@ -48,7 +52,8 @@ async def get_mcp_resource(session: ClientSession, uri: str) -> list[Blob]:
         return []
 
     return [
-        convert_mcp_resource_to_langchain_blob(uri, content) for content in contents_result.contents
+        convert_mcp_resource_to_langchain_blob(uri, content)
+        for content in contents_result.contents
     ]
 
 

langchain_mcp_adapters/sessions.py

@@ -95,7 +95,7 @@ class StdioConnection(TypedDict):
 
 
 class SSEConnection(TypedDict):
-    """Configuration for Server-Sent Events (SSE) transport connections to MCP servers."""
+    """Configuration for Server-Sent Events (SSE) transport connections to MCP."""
 
     transport: Literal["sse"]
 
@@ -172,7 +172,9 @@ class WebsocketConnection(TypedDict):
     """Additional keyword arguments to pass to the ClientSession"""
 
 
-Connection = StdioConnection | SSEConnection | StreamableHttpConnection | WebsocketConnection
+Connection = (
+    StdioConnection | SSEConnection | StreamableHttpConnection | WebsocketConnection
+)
 
 
 @asynccontextmanager
@@ -183,7 +185,9 @@ async def _create_stdio_session(  # noqa: PLR0913
     env: dict[str, str] | None = None,
     cwd: str | Path | None = None,
     encoding: str = DEFAULT_ENCODING,
-    encoding_error_handler: Literal["strict", "ignore", "replace"] = DEFAULT_ENCODING_ERROR_HANDLER,
+    encoding_error_handler: Literal[
+        "strict", "ignore", "replace"
+    ] = DEFAULT_ENCODING_ERROR_HANDLER,
     session_kwargs: dict[str, Any] | None = None,
 ) -> AsyncIterator[ClientSession]:
     """Create a new session to an MCP server using stdio.
@@ -201,7 +205,7 @@ async def _create_stdio_session(  # noqa: PLR0913
         An initialized ClientSession.
     """
     # NOTE: execution commands (e.g., `uvx` / `npx`) require PATH envvar to be set.
-    # To address this, we automatically inject existing PATH envvar into the `env` value,
+    # To address this, we automatically inject existing PATH envvar into the `env`,
     # if it's not already set.
     env = env or {}
     if "PATH" not in env:
@@ -282,7 +286,8 @@ async def _create_streamable_http_session(  # noqa: PLR0913
         url: URL of the endpoint to connect to.
         headers: HTTP headers to send to the endpoint.
         timeout: HTTP timeout.
-        sse_read_timeout: How long the client will wait for a new event before disconnecting.
+        sse_read_timeout: How long the client will wait for a new event before
+            disconnecting.
         terminate_on_close: Whether to terminate the session on close.
         session_kwargs: Additional keyword arguments to pass to the ClientSession.
         httpx_client_factory: Custom factory for httpx.AsyncClient (optional).
@@ -334,7 +339,7 @@ async def _create_websocket_session(
     except ImportError:
         msg = (
             "Could not import websocket_client. "
-            "To use Websocket connections, please install the required dependency with: "
+            "To use Websocket connections, please install the required dependency: "
             "'pip install mcp[ws]' or 'pip install websockets'"
         )
         raise ImportError(msg) from None

langchain_mcp_adapters/tools.py

@@ -6,7 +6,12 @@
 
 from typing import Any, cast, get_args
 
-from langchain_core.tools import BaseTool, InjectedToolArg, StructuredTool, ToolException
+from langchain_core.tools import (
+    BaseTool,
+    InjectedToolArg,
+    StructuredTool,
+    ToolException,
+)
 from langchain_core.tools.base import get_all_basemodel_annotations
 from mcp import ClientSession
 from mcp.server.fastmcp.tools import Tool as FastMCPTool
@@ -172,7 +177,8 @@ async def load_mcp_tools(
         tools = await _list_all_tools(session)
 
     return [
-        convert_mcp_tool_to_langchain_tool(session, tool, connection=connection) for tool in tools
+        convert_mcp_tool_to_langchain_tool(session, tool, connection=connection)
+        for tool in tools
     ]
 
 
@@ -225,7 +231,9 @@ def to_fastmcp(tool: BaseTool) -> FastMCPTool:
         field: (field_info.annotation, field_info)
         for field, field_info in tool.tool_call_schema.model_fields.items()
     }
-    arg_model = create_model(f"{tool.name}Arguments", **field_definitions, __base__=ArgModelBase)
+    arg_model = create_model(
+        f"{tool.name}Arguments", **field_definitions, __base__=ArgModelBase
+    )
     fn_metadata = FuncMetadata(arg_model=arg_model)
 
     # We'll use an Any type for the function return type.

pyproject.toml

@@ -45,13 +45,12 @@ asyncio_mode = "auto"
 asyncio_default_fixture_loop_scope = "function"
 
 [tool.ruff]
-line-length = 100
+line-length = 88 
 target-version = "py310"
 
 [tool.ruff.lint]
 select = [ "ALL",]
 ignore = [
-  "E501", # line-length
   "COM812", # conflict with formatter
 ]
 

tests/conftest.py

@@ -46,7 +46,9 @@ def websocket_server(websocket_server_port: int) -> Generator[None, None, None]:
     proc.kill()
     proc.join(timeout=2)
     if proc.is_alive():
-        raise RuntimeError("Server process is still alive after attempting to terminate it")
+        raise RuntimeError(
+            "Server process is still alive after attempting to terminate it"
+        )
 
 
 @pytest.fixture
@@ -58,7 +60,9 @@ def socket_enabled():
         pytest_socket.enable_socket()
         previous_state = pytest_socket.socket_allow_hosts()
         # Only allow connections to localhost
-        pytest_socket.socket_allow_hosts(["127.0.0.1", "localhost"], allow_unix_socket=True)
+        pytest_socket.socket_allow_hosts(
+            ["127.0.0.1", "localhost"], allow_unix_socket=True
+        )
         yield
     finally:
         # Restore previous state

tests/servers/math_server.py

@@ -20,7 +20,10 @@ def configure_assistant(skills: str) -> list[dict]:
     return [
         {
             "role": "assistant",
-            "content": f"You are a helpful assistant. You have the following skills: {skills}. Always use only one tool at a time.",
+            "content": (
+                f"You are a helpful assistant. You have these skills: {skills}. "
+                "Always use only one tool at a time."
+            ),
         },
     ]
 

tests/test_client.py

@@ -15,17 +15,28 @@ async def test_multi_server_mcp_client(
     websocket_server,
     websocket_server_port: int,
 ):
-    """Test that the MultiServerMCPClient can connect to multiple servers and load tools."""
+    """Test that MultiServerMCPClient can connect to multiple servers and load tools."""
     # Get the absolute path to the server scripts
     current_dir = Path(__file__).parent
     math_server_path = os.path.join(current_dir, "servers/math_server.py")
     weather_server_path = os.path.join(current_dir, "servers/weather_server.py")
 
     client = MultiServerMCPClient(
         {
-            "math": {"command": "python", "args": [math_server_path], "transport": "stdio"},
-            "weather": {"command": "python", "args": [weather_server_path], "transport": "stdio"},
-            "time": {"url": f"ws://127.0.0.1:{websocket_server_port}/ws", "transport": "websocket"},
+            "math": {
+                "command": "python",
+                "args": [math_server_path],
+                "transport": "stdio",
+            },
+            "weather": {
+                "command": "python",
+                "args": [weather_server_path],
+                "transport": "stdio",
+            },
+            "time": {
+                "url": f"ws://127.0.0.1:{websocket_server_port}/ws",
+                "transport": "websocket",
+            },
         },
     )
     # Check that we have tools from both servers
@@ -93,8 +104,15 @@ async def test_multi_server_connect_methods(
     # Initialize client without initial connections
     client = MultiServerMCPClient(
         {
-            "math": {"command": "python", "args": [math_server_path], "transport": "stdio"},
-            "time": {"url": f"ws://127.0.0.1:{websocket_server_port}/ws", "transport": "websocket"},
+            "math": {
+                "command": "python",
+                "args": [math_server_path],
+                "transport": "stdio",
+            },
+            "time": {
+                "url": f"ws://127.0.0.1:{websocket_server_port}/ws",
+                "transport": "websocket",
+            },
         },
     )
     tool_names = set()
@@ -127,7 +145,13 @@ async def test_get_prompt():
     math_server_path = os.path.join(current_dir, "servers/math_server.py")
 
     client = MultiServerMCPClient(
-        {"math": {"command": "python", "args": [math_server_path], "transport": "stdio"}},
+        {
+            "math": {
+                "command": "python",
+                "args": [math_server_path],
+                "transport": "stdio",
+            }
+        },
     )
     # Test getting a prompt from the math server
     messages = await client.get_prompt(