From 7dbe1b8b59b8c5cf06e833df0ea3c2fff8c20429 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 21 Apr 2025 12:06:19 +0200
Subject: [PATCH 01/10] Deprecate SSEServerInfo base_url

---
 .../tools/mcp/mcp_tool.py                     | 49 +++++++++++++++----
 1 file changed, 40 insertions(+), 9 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index 8f8e3eaf14..9f6edcbf7a 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -351,16 +351,31 @@ class SSEClient(MCPClient):
     MCP client that connects to servers using SSE transport.
     """
 
-    def __init__(self, base_url: str, token: str | None = None, timeout: int = 5) -> None:
+    def __init__(self, url: str | None = None, base_url: str | None = None, token: str | None = None, timeout: int = 5) -> None:
         """
         Initialize an SSE MCP client.
 
-        :param base_url: Base URL of the server
+        :param url: Full URL of the server (including /sse endpoint)
+        :param base_url: Base URL of the server (deprecated, use url instead)
         :param token: Authentication token for the server (optional)
         :param timeout: Connection timeout in seconds
         """
         super().__init__()
-        self.base_url: str = base_url.rstrip("/")  # Remove any trailing slashes
+        if url is None and base_url is None:
+            raise ValueError("Either url or base_url must be provided")
+        if url is not None and base_url is not None:
+            raise ValueError("Only one of url or base_url should be provided")
+
+        if base_url is not None:
+            import warnings
+            warnings.warn(
+                "base_url is deprecated and will be removed in a future version. Use url instead.",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+            self.url = f"{base_url.rstrip('/')}/sse"  # Remove any trailing slashes and add /sse
+        else:
+            self.url = url
         self.token: str | None = token
         self.timeout: int = timeout
 
@@ -371,12 +386,11 @@ async def connect(self) -> list[Tool]:
         :returns: List of available tools on the server
         :raises MCPConnectionError: If connection to the server fails
         """
-        sse_url = f"{self.base_url}/sse"
         headers = {"Authorization": f"Bearer {self.token}"} if self.token else None
         sse_transport = await self.exit_stack.enter_async_context(
-            sse_client(sse_url, headers=headers, timeout=self.timeout)
+            sse_client(self.url, headers=headers, timeout=self.timeout)
         )
-        return await self._initialize_session_with_transport(sse_transport, f"HTTP server at {self.base_url}")
+        return await self._initialize_session_with_transport(sse_transport, f"HTTP server at {self.url}")
 
 
 @dataclass
@@ -432,22 +446,39 @@ class SSEServerInfo(MCPServerInfo):
     """
     Data class that encapsulates SSE MCP server connection parameters.
 
-    :param base_url: Base URL of the MCP server
+    :param url: Full URL of the MCP server (including /sse endpoint)
+    :param base_url: Base URL of the MCP server (deprecated, use url instead)
     :param token: Authentication token for the server (optional)
     :param timeout: Connection timeout in seconds
     """
 
-    base_url: str
+    url: str | None = None
+    base_url: str | None = None  # deprecated
     token: str | None = None
     timeout: int = 30
 
+    def __post_init__(self):
+        """Validate that either url or base_url is provided."""
+        if self.url is None and self.base_url is None:
+            raise ValueError("Either url or base_url must be provided")
+        if self.url is not None and self.base_url is not None:
+            raise ValueError("Only one of url or base_url should be provided")
+
     def create_client(self) -> MCPClient:
         """
         Create an SSE MCP client.
 
         :returns: Configured HttpMCPClient instance
         """
-        return SSEClient(self.base_url, self.token, self.timeout)
+        if self.base_url is not None:
+            import warnings
+            warnings.warn(
+                "base_url is deprecated and will be removed in a future version. Use url instead.",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+            return SSEClient(base_url=self.base_url, token=self.token, timeout=self.timeout)
+        return SSEClient(url=self.url, token=self.token, timeout=self.timeout)
 
 
 @dataclass

From 56ef24e737f599bebee071b7a2c08175f5fe6835 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 21 Apr 2025 12:21:08 +0200
Subject: [PATCH 02/10] Lint and mypy

---
 .../tools/mcp/mcp_tool.py                     | 25 +++++++++++++------
 1 file changed, 17 insertions(+), 8 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index 9f6edcbf7a..a6680a5098 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -351,7 +351,9 @@ class SSEClient(MCPClient):
     MCP client that connects to servers using SSE transport.
     """
 
-    def __init__(self, url: str | None = None, base_url: str | None = None, token: str | None = None, timeout: int = 5) -> None:
+    def __init__(
+        self, url: str | None = None, base_url: str | None = None, token: str | None = None, timeout: int = 5
+    ) -> None:
         """
         Initialize an SSE MCP client.
 
@@ -362,19 +364,23 @@ def __init__(self, url: str | None = None, base_url: str | None = None, token: s
         """
         super().__init__()
         if url is None and base_url is None:
-            raise ValueError("Either url or base_url must be provided")
-        if url is not None and base_url is not None:
-            raise ValueError("Only one of url or base_url should be provided")
+            message = "Either url or base_url must be provided"
+            raise ValueError(message)
+        if url and base_url:
+            message = "Only one of url or base_url should be provided"
+            raise ValueError(message)
 
-        if base_url is not None:
+        if base_url:
             import warnings
+
             warnings.warn(
                 "base_url is deprecated and will be removed in a future version. Use url instead.",
                 DeprecationWarning,
                 stacklevel=2,
             )
             self.url = f"{base_url.rstrip('/')}/sse"  # Remove any trailing slashes and add /sse
-        else:
+        elif url:
+            # Always true here in this branch but mypy doesn't know that
             self.url = url
         self.token: str | None = token
         self.timeout: int = timeout
@@ -460,9 +466,11 @@ class SSEServerInfo(MCPServerInfo):
     def __post_init__(self):
         """Validate that either url or base_url is provided."""
         if self.url is None and self.base_url is None:
-            raise ValueError("Either url or base_url must be provided")
+            message = "Either url or base_url must be provided"
+            raise ValueError(message)
         if self.url is not None and self.base_url is not None:
-            raise ValueError("Only one of url or base_url should be provided")
+            message = "Only one of url or base_url should be provided"
+            raise ValueError(message)
 
     def create_client(self) -> MCPClient:
         """
@@ -472,6 +480,7 @@ def create_client(self) -> MCPClient:
         """
         if self.base_url is not None:
             import warnings
+
             warnings.warn(
                 "base_url is deprecated and will be removed in a future version. Use url instead.",
                 DeprecationWarning,

From 07113d99fa1bd31db64613ba0cce9d676fd98d78 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 21 Apr 2025 14:18:51 +0200
Subject: [PATCH 03/10] Leave base_url field until deprecation removed

---
 .../mcp/src/haystack_integrations/tools/mcp/mcp_tool.py         | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index a6680a5098..c57f4b9eeb 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -382,6 +382,8 @@ def __init__(
         elif url:
             # Always true here in this branch but mypy doesn't know that
             self.url = url
+
+        self.base_url = base_url  # leave this here for backwards compatibility (and remove in future)
         self.token: str | None = token
         self.timeout: int = timeout
 

From 3c9e9b63a145ab0b5fffdcec355ead65d5a5108f Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 21 Apr 2025 14:36:37 +0200
Subject: [PATCH 04/10] Add unit test, final touches

---
 .../tools/mcp/mcp_tool.py                     | 20 ++++++++++---------
 integrations/mcp/tests/test_mcp_tool.py       | 20 +++++++++++++++++++
 2 files changed, 31 insertions(+), 9 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index c57f4b9eeb..2bc675571e 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -467,20 +467,14 @@ class SSEServerInfo(MCPServerInfo):
 
     def __post_init__(self):
         """Validate that either url or base_url is provided."""
-        if self.url is None and self.base_url is None:
+        if not self.url and not self.base_url:
             message = "Either url or base_url must be provided"
             raise ValueError(message)
-        if self.url is not None and self.base_url is not None:
+        if self.url and self.base_url:
             message = "Only one of url or base_url should be provided"
             raise ValueError(message)
 
-    def create_client(self) -> MCPClient:
-        """
-        Create an SSE MCP client.
-
-        :returns: Configured HttpMCPClient instance
-        """
-        if self.base_url is not None:
+        if self.base_url:
             import warnings
 
             warnings.warn(
@@ -488,6 +482,14 @@ def create_client(self) -> MCPClient:
                 DeprecationWarning,
                 stacklevel=2,
             )
+
+    def create_client(self) -> MCPClient:
+        """
+        Create an SSE MCP client.
+
+        :returns: Configured HttpMCPClient instance
+        """
+        if self.base_url:
             return SSEClient(base_url=self.base_url, token=self.token, timeout=self.timeout)
         return SSEClient(url=self.url, token=self.token, timeout=self.timeout)
 
diff --git a/integrations/mcp/tests/test_mcp_tool.py b/integrations/mcp/tests/test_mcp_tool.py
index e42866cca2..b56bbc647d 100644
--- a/integrations/mcp/tests/test_mcp_tool.py
+++ b/integrations/mcp/tests/test_mcp_tool.py
@@ -132,6 +132,26 @@ def test_http_server_info_serde(self):
         assert new_info.token == "test-token"
         assert new_info.timeout == 45
 
+    def test_url_base_url_validation(self):
+        """Test validation of url and base_url parameters."""
+        # Test with neither url nor base_url
+        with pytest.raises(ValueError, match="Either url or base_url must be provided"):
+            SSEServerInfo()
+
+        # Test with both url and base_url
+        with pytest.raises(ValueError, match="Only one of url or base_url should be provided"):
+            SSEServerInfo(url="http://example.com/sse", base_url="http://example.com")
+
+        # Test with only url
+        server_info = SSEServerInfo(url="http://example.com/sse")
+        assert server_info.url == "http://example.com/sse"
+        assert server_info.base_url is None
+
+        # Test with only base_url (deprecated but supported)
+        with pytest.warns(DeprecationWarning, match="base_url is deprecated"):
+            server_info = SSEServerInfo(base_url="http://example.com")
+            assert server_info.base_url == "http://example.com"  # Should preserve original base_url
+
     def test_stdio_server_info_serde(self):
         """Test serialization/deserialization of StdioServerInfo."""
         server_info = StdioServerInfo(command="python", args=["-m", "mcp_server_time"], env={"TEST_ENV": "value"})

From 9ee6cecd1b8c3525648602f0fc80f43e4d7bac8e Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 28 Apr 2025 15:08:18 +0200
Subject: [PATCH 05/10] Update example

---
 .../mcp/src/haystack_integrations/tools/mcp/mcp_tool.py         | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index 2bc675571e..aa6aace472 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -535,7 +535,7 @@ class MCPTool(Tool):
     # Create tool instance
     tool = MCPTool(
         name="add",
-        server_info=SSEServerInfo(base_url="http://localhost:8000")
+        server_info=SSEServerInfo(url="http://localhost:8000/sse")
     )
 
     # Use the tool

From b224aa423b1c9e3466ff36ff855248c393a7ac9a Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 28 Apr 2025 15:35:31 +0200
Subject: [PATCH 06/10] More URL checks, better error reporting

---
 .../tools/mcp/mcp_tool.py                     | 10 +++++++
 .../tools/mcp/mcp_toolset.py                  | 26 +++++++++++++++----
 2 files changed, 31 insertions(+), 5 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index aa6aace472..dcf02100b0 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -16,6 +16,7 @@
 from haystack.core.serialization import generate_qualified_class_name, import_class_by_name
 from haystack.tools import Tool
 from haystack.tools.errors import ToolInvocationError
+from haystack.utils.url_validation import is_valid_http_url
 
 from mcp import ClientSession, StdioServerParameters, types
 from mcp.client.sse import sse_client
@@ -475,6 +476,10 @@ def __post_init__(self):
             raise ValueError(message)
 
         if self.base_url:
+            if not is_valid_http_url(self.base_url):
+                message = f"Invalid base_url: {self.base_url}"
+                raise ValueError(message)
+
             import warnings
 
             warnings.warn(
@@ -483,6 +488,11 @@ def __post_init__(self):
                 stacklevel=2,
             )
 
+        if self.url:
+            if not is_valid_http_url(self.url):
+                message = f"Invalid url: {self.url}"
+                raise ValueError(message)
+
     def create_client(self) -> MCPClient:
         """
         Create an SSE MCP client.
diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
index df0bd15994..d7bb358e87 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
@@ -3,6 +3,7 @@
 # SPDX-License-Identifier: Apache-2.0
 
 from typing import Any
+from urllib.parse import urlparse
 
 import httpx
 from exceptiongroup import ExceptionGroup
@@ -88,7 +89,7 @@ class MCPToolset(Toolset):
 
     # Create the toolset with an SSE connection
     sse_toolset = MCPToolset(
-        server_info=SSEServerInfo(base_url="http://some-remote-server.com:8000"),
+        server_info=SSEServerInfo(url="http://some-remote-server.com:8000/sse"),
         tool_names=["add", "subtract"]  # Only include specific tools
     )
 
@@ -175,7 +176,8 @@ def invoke_tool(**kwargs) -> Any:
 
         except Exception as e:
             if isinstance(self.server_info, SSEServerInfo):
-                base_message = f"Failed to connect to SSE server at {self.server_info.base_url}"
+                url = self.server_info.url or self.server_info.base_url
+                base_message = f"Failed to connect to SSE server at {url}"
                 checks = ["1. The server is running"]
 
                 # Check for ConnectError in exception group or direct exception
@@ -184,10 +186,24 @@ def invoke_tool(**kwargs) -> Any:
                 )
 
                 if has_connect_error:
-                    port = self.server_info.base_url.split(":")[-1]
-                    checks.append(f"2. The address and port are correct (attempted port: {port})")
+                    # Use urlparse to reliably get scheme, hostname, and port
+                    parsed_url = urlparse(url)
+                    port_str = ""
+                    if parsed_url.port:
+                        port_str = str(parsed_url.port)
+                    elif parsed_url.scheme == "http":
+                        port_str = "80 (default)"
+                    elif parsed_url.scheme == "https":
+                        port_str = "443 (default)"
+                    else:
+                        port_str = "unknown (scheme not http/https or missing)"  # Or handle more schemes if needed
+
+                    # Ensure hostname is handled correctly (it might be None)
+                    hostname_str = str(parsed_url.hostname) if parsed_url.hostname else "<unknown>"
+                    message = f"2. The address '{hostname_str}' and port '{port_str}' are correct"
+                    checks.append(message)
                     checks.append("3. There are no firewall or network connectivity issues")
-                    message = f"{base_message}. Please check if:\n" + "\n".join(checks)
+                    message = f"{base_message}. Please check if:\n" + "\\n".join(checks)
                 else:
                     message = f"{base_message}: {e}"
             elif isinstance(self.server_info, StdioServerInfo):  # stdio connection

From 9f737b46193331cde7cce5c60ccb576fba532fce Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 28 Apr 2025 15:47:19 +0200
Subject: [PATCH 07/10] Simplify internals

---
 .../tools/mcp/mcp_tool.py                     | 44 ++++---------------
 integrations/mcp/tests/test_mcp_tool.py       |  2 +-
 2 files changed, 10 insertions(+), 36 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index dcf02100b0..a2b2b47cd5 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -352,41 +352,16 @@ class SSEClient(MCPClient):
     MCP client that connects to servers using SSE transport.
     """
 
-    def __init__(
-        self, url: str | None = None, base_url: str | None = None, token: str | None = None, timeout: int = 5
-    ) -> None:
+    def __init__(self, server_info: "SSEServerInfo") -> None:
         """
-        Initialize an SSE MCP client.
+        Initialize an SSE MCP client using server configuration.
 
-        :param url: Full URL of the server (including /sse endpoint)
-        :param base_url: Base URL of the server (deprecated, use url instead)
-        :param token: Authentication token for the server (optional)
-        :param timeout: Connection timeout in seconds
+        :param server_info: Configuration object containing URL, token, timeout, etc.
         """
         super().__init__()
-        if url is None and base_url is None:
-            message = "Either url or base_url must be provided"
-            raise ValueError(message)
-        if url and base_url:
-            message = "Only one of url or base_url should be provided"
-            raise ValueError(message)
-
-        if base_url:
-            import warnings
-
-            warnings.warn(
-                "base_url is deprecated and will be removed in a future version. Use url instead.",
-                DeprecationWarning,
-                stacklevel=2,
-            )
-            self.url = f"{base_url.rstrip('/')}/sse"  # Remove any trailing slashes and add /sse
-        elif url:
-            # Always true here in this branch but mypy doesn't know that
-            self.url = url
-
-        self.base_url = base_url  # leave this here for backwards compatibility (and remove in future)
-        self.token: str | None = token
-        self.timeout: int = timeout
+        self.url: str = server_info.url or f"{server_info.base_url}/sse"
+        self.token: str | None = server_info.token
+        self.timeout: int = server_info.timeout
 
     async def connect(self) -> list[Tool]:
         """
@@ -497,11 +472,10 @@ def create_client(self) -> MCPClient:
         """
         Create an SSE MCP client.
 
-        :returns: Configured HttpMCPClient instance
+        :returns: Configured SSEClient instance
         """
-        if self.base_url:
-            return SSEClient(base_url=self.base_url, token=self.token, timeout=self.timeout)
-        return SSEClient(url=self.url, token=self.token, timeout=self.timeout)
+        # Pass the validated SSEServerInfo instance directly
+        return SSEClient(server_info=self)
 
 
 @dataclass
diff --git a/integrations/mcp/tests/test_mcp_tool.py b/integrations/mcp/tests/test_mcp_tool.py
index e5d595ae16..1eef41ca16 100644
--- a/integrations/mcp/tests/test_mcp_tool.py
+++ b/integrations/mcp/tests/test_mcp_tool.py
@@ -177,7 +177,7 @@ def test_create_client(self):
         http_client = http_info.create_client()
         stdio_client = stdio_info.create_client()
 
-        assert http_client.base_url == "http://example.com"
+        assert http_client.url == "http://example.com/sse"
         assert stdio_client.command == "python"
 
 

From fec96533b8fe627bc02b1129531f5f9a16faa913 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 28 Apr 2025 16:05:01 +0200
Subject: [PATCH 08/10] Minor simplification

---
 .../tools/mcp/mcp_tool.py                     | 21 +++++++++++--------
 .../tools/mcp/mcp_toolset.py                  |  5 ++---
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index a2b2b47cd5..2d288b3e9b 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -5,6 +5,7 @@
 import asyncio
 import concurrent.futures
 import threading
+import warnings
 from abc import ABC, abstractmethod
 from collections.abc import Coroutine
 from contextlib import AsyncExitStack
@@ -359,7 +360,10 @@ def __init__(self, server_info: "SSEServerInfo") -> None:
         :param server_info: Configuration object containing URL, token, timeout, etc.
         """
         super().__init__()
-        self.url: str = server_info.url or f"{server_info.base_url}/sse"
+
+        # in post_init we validate the url and set the url field so it is guaranteed to be valid
+        # safely ignore the mypy warning here
+        self.url: str = server_info.url  # type: ignore[assignment]
         self.token: str | None = server_info.token
         self.timeout: int = server_info.timeout
 
@@ -447,26 +451,25 @@ def __post_init__(self):
             message = "Either url or base_url must be provided"
             raise ValueError(message)
         if self.url and self.base_url:
-            message = "Only one of url or base_url should be provided"
-            raise ValueError(message)
+            message = "Only one of url or base_url should be provided, if both are provided, base_url will be ignored"
+            warnings.warn(message, DeprecationWarning, stacklevel=2)
 
         if self.base_url:
             if not is_valid_http_url(self.base_url):
                 message = f"Invalid base_url: {self.base_url}"
                 raise ValueError(message)
 
-            import warnings
-
             warnings.warn(
                 "base_url is deprecated and will be removed in a future version. Use url instead.",
                 DeprecationWarning,
                 stacklevel=2,
             )
+            # from now on only use url for the lifetime of the SSEServerInfo instance, never base_url
+            self.url = f"{self.base_url.rstrip('/')}/sse"
 
-        if self.url:
-            if not is_valid_http_url(self.url):
-                message = f"Invalid url: {self.url}"
-                raise ValueError(message)
+        elif not is_valid_http_url(self.url):
+            message = f"Invalid url: {self.url}"
+            raise ValueError(message)
 
     def create_client(self) -> MCPClient:
         """
diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
index d7bb358e87..93928b84b9 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_toolset.py
@@ -176,8 +176,7 @@ def invoke_tool(**kwargs) -> Any:
 
         except Exception as e:
             if isinstance(self.server_info, SSEServerInfo):
-                url = self.server_info.url or self.server_info.base_url
-                base_message = f"Failed to connect to SSE server at {url}"
+                base_message = f"Failed to connect to SSE server at {self.server_info.url}"
                 checks = ["1. The server is running"]
 
                 # Check for ConnectError in exception group or direct exception
@@ -187,7 +186,7 @@ def invoke_tool(**kwargs) -> Any:
 
                 if has_connect_error:
                     # Use urlparse to reliably get scheme, hostname, and port
-                    parsed_url = urlparse(url)
+                    parsed_url = urlparse(self.server_info.url)
                     port_str = ""
                     if parsed_url.port:
                         port_str = str(parsed_url.port)

From 05f671d9fbf4608e1ad921248ca60dcad4265990 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 28 Apr 2025 16:08:59 +0200
Subject: [PATCH 09/10] Small test fix

---
 integrations/mcp/tests/test_mcp_tool.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/integrations/mcp/tests/test_mcp_tool.py b/integrations/mcp/tests/test_mcp_tool.py
index 1eef41ca16..cf6d106a42 100644
--- a/integrations/mcp/tests/test_mcp_tool.py
+++ b/integrations/mcp/tests/test_mcp_tool.py
@@ -139,7 +139,7 @@ def test_url_base_url_validation(self):
             SSEServerInfo()
 
         # Test with both url and base_url
-        with pytest.raises(ValueError, match="Only one of url or base_url should be provided"):
+        with pytest.warns(DeprecationWarning, match="base_url is deprecated"):
             SSEServerInfo(url="http://example.com/sse", base_url="http://example.com")
 
         # Test with only url

From 143a9bbd99d902f939fa8c96091ebbac1ebcdfc8 Mon Sep 17 00:00:00 2001
From: Vladimir Blagojevic <dovlex@gmail.com>
Date: Mon, 5 May 2025 15:51:13 +0200
Subject: [PATCH 10/10] PR feedback

---
 .../mcp/src/haystack_integrations/tools/mcp/mcp_tool.py         | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
index 2d288b3e9b..68f1bf7de0 100644
--- a/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
+++ b/integrations/mcp/src/haystack_integrations/tools/mcp/mcp_tool.py
@@ -475,7 +475,7 @@ def create_client(self) -> MCPClient:
         """
         Create an SSE MCP client.
 
-        :returns: Configured SSEClient instance
+        :returns: Configured MCPClient instance
         """
         # Pass the validated SSEServerInfo instance directly
         return SSEClient(server_info=self)