lint: enable TRY003,TRY004 (#248)

Enable TRY003, TRY004

Author: eyurtsev

examples/servers/streamable-http-stateless/mcp_simple_streamablehttp_stateless/server.py

@@ -2,7 +2,6 @@
 import logging
 from collections.abc import AsyncIterator
 
-import anyio
 import click
 import mcp.types as types
 from mcp.server.lowlevel import Server

langchain_mcp_adapters/client.py

@@ -98,9 +98,8 @@ async def session(
 
         """
         if server_name not in self.connections:
-            raise ValueError(
-                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}', expected one of '{list(self.connections.keys())}'"
+            raise ValueError(msg)
 
         async with create_session(self.connections[server_name]) as session:
             if auto_initialize:
@@ -122,9 +121,8 @@ 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:
-                raise ValueError(
-                    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}', 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] = []

langchain_mcp_adapters/prompts.py

@@ -22,9 +22,11 @@ def convert_mcp_prompt_message_to_langchain_message(
             return HumanMessage(content=message.content.text)
         if message.role == "assistant":
             return AIMessage(content=message.content.text)
-        raise ValueError(f"Unsupported prompt message role: {message.role}")
+        msg = f"Unsupported prompt message role: {message.role}"
+        raise ValueError(msg)
 
-    raise ValueError(f"Unsupported prompt message content type: {message.content.type}")
+    msg = f"Unsupported prompt message content type: {message.content.type}"
+    raise ValueError(msg)
 
 
 async def load_mcp_prompt(

langchain_mcp_adapters/resources.py

@@ -21,7 +21,8 @@ def convert_mcp_resource_to_langchain_blob(resource_uri: str, contents: Resource
     elif isinstance(contents, BlobResourceContents):
         data = base64.b64decode(contents.blob)
     else:
-        raise ValueError(f"Unsupported content type for URI {resource_uri}")
+        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})
 
@@ -78,6 +79,7 @@ async def load_mcp_resources(
             resource_blobs = await get_mcp_resource(session, uri)
             blobs.extend(resource_blobs)
         except Exception as e:
-            raise RuntimeError(f"Error fetching resource {uri}") from e
+            msg = f"Error fetching resource {uri}"
+            raise RuntimeError(msg) from e
 
     return blobs

langchain_mcp_adapters/sessions.py

@@ -89,7 +89,7 @@ class SSEConnection(TypedDict):
     sse_read_timeout: NotRequired[float]
     """SSE read timeout.
 
-    Default is 300 seconds (5 minutes). This is how long the client will 
+    Default is 300 seconds (5 minutes). This is how long the client will
     wait for a new event before disconnecting.
     """
 
@@ -281,11 +281,12 @@ async def _create_websocket_session(
     try:
         from mcp.client.websocket import websocket_client
     except ImportError:
-        raise ImportError(
-            "Could not import websocket_client. ",
-            "To use Websocket connections, please install the required dependency with: ",
-            "'pip install mcp[ws]' or 'pip install websockets'",
-        ) from None
+        msg = (
+            "Could not import websocket_client. "
+            "To use Websocket connections, please install the required dependency with: "
+            "'pip install mcp[ws]' or 'pip install websockets'"
+        )
+        raise ImportError(msg) from None
 
     async with websocket_client(url) as (read, write):
         async with ClientSession(read, write, **(session_kwargs or {})) as session:
@@ -307,40 +308,47 @@ async def create_session(connection: Connection) -> AsyncIterator[ClientSession]
         A ClientSession
     """
     if "transport" not in connection:
-        raise ValueError(
+        msg = (
             "Configuration error: Missing 'transport' key in server configuration. "
             "Each server must include 'transport' with one of: "
             "'stdio', 'sse', 'websocket', 'streamable_http'. "
             "Please refer to the langchain-mcp-adapters documentation for more details."
         )
+        raise ValueError(msg)
 
     transport = connection["transport"]
     params = {k: v for k, v in connection.items() if k != "transport"}
 
     if transport == "sse":
         if "url" not in params:
-            raise ValueError("'url' parameter is required for SSE connection")
+            msg = "'url' parameter is required for SSE connection"
+            raise ValueError(msg)
         async with _create_sse_session(**params) as session:
             yield session
     elif transport == "streamable_http":
         if "url" not in params:
-            raise ValueError("'url' parameter is required for Streamable HTTP connection")
+            msg = "'url' parameter is required for Streamable HTTP connection"
+            raise ValueError(msg)
         async with _create_streamable_http_session(**params) as session:
             yield session
     elif transport == "stdio":
         if "command" not in params:
-            raise ValueError("'command' parameter is required for stdio connection")
+            msg = "'command' parameter is required for stdio connection"
+            raise ValueError(msg)
         if "args" not in params:
-            raise ValueError("'args' parameter is required for stdio connection")
+            msg = "'args' parameter is required for stdio connection"
+            raise ValueError(msg)
         async with _create_stdio_session(**params) as session:
             yield session
     elif transport == "websocket":
         if "url" not in params:
-            raise ValueError("'url' parameter is required for Websocket connection")
+            msg = "'url' parameter is required for Websocket connection"
+            raise ValueError(msg)
         async with _create_websocket_session(**params) as session:
             yield session
     else:
-        raise ValueError(
+        msg = (
             f"Unsupported transport: {transport}. "
             f"Must be one of: 'stdio', 'sse', 'websocket', 'streamable_http'"
         )
+        raise ValueError(msg)

langchain_mcp_adapters/tools.py

@@ -47,7 +47,8 @@ async def _list_all_tools(session: ClientSession) -> list[MCPTool]:
     while True:
         iterations += 1
         if iterations > MAX_ITERATIONS:
-            raise RuntimeError("Reached max of 1000 iterations while listing tools.")
+            msg = "Reached max of 1000 iterations while listing tools."
+            raise RuntimeError(msg)
 
         list_tools_page_result = await session.list_tools(cursor=current_cursor)
 
@@ -79,7 +80,8 @@ def convert_mcp_tool_to_langchain_tool(
 
     """
     if session is None and connection is None:
-        raise ValueError("Either a session or a connection config must be provided")
+        msg = "Either a session or a connection config must be provided"
+        raise ValueError(msg)
 
     async def call_tool(
         **arguments: dict[str, Any],
@@ -116,7 +118,8 @@ async def load_mcp_tools(
 
     """
     if session is None and connection is None:
-        raise ValueError("Either a session or a connection config must be provided")
+        msg = "Either a session or a connection config must be provided"
+        raise ValueError(msg)
 
     if session is None:
         # If a session is not provided, we will create one on the fly
@@ -151,10 +154,11 @@ def _is_injected_arg_type(type_: type) -> bool:
 def to_fastmcp(tool: BaseTool) -> FastMCPTool:
     """Convert a LangChain tool to a FastMCP tool."""
     if not issubclass(tool.args_schema, BaseModel):
-        raise ValueError(
+        msg = (
             "Tool args_schema must be a subclass of pydantic.BaseModel. "
             "Tools with dict args schema are not supported."
         )
+        raise TypeError(msg)
 
     parameters = tool.tool_call_schema.model_json_schema()
     field_definitions = {

pyproject.toml

@@ -69,8 +69,6 @@ ignore = [
   "SIM117",
   "TC002",
   "TC003",
-  "TRY003",
-  "TRY004",
 ]