Here’s why the latest run blew up and what to change so the **Swarms Agent + MCP** combo finally works:

---

### 1  Fix the import that’s blowing up

`mcp` exposes **ClientSession**, not **Client**.  
Change the top‑of‑file imports in **swarms/tools/mcp_integration.py**

```diff
- from mcp import Client as ClientSession
- from fastmcp.client.sse import sse_client        # (this package doesn’t exist)
+ from mcp import ClientSession                    # core SDK class
+ from mcp.client.sse import sse_client            # SSE transport helper
```

(See MCP quick‑start that shows `from mcp import ClientSession` citeturn3search8)

---

### 2  Use `typing_extensions.NotRequired` on Python ≤ 3.10

Python 3.11 added `typing.NotRequired`; on 3.10 you must pull it from
`typing_extensions`:

```python
from typing_extensions import NotRequired, TypedDict
```

You already have that line – keep it.

---

### 3  Let your `Agent` actually hold the server list

The attribute‑error you saw (`'Agent' object has no attribute 'mcp_servers'`)
happens because the constructor parameter was commented out.

Add the param and stash it:

```diff
-class Agent:
-    def __init__(self,
+class Agent:
+    def __init__(self,
         ...
-        # mcp_servers: List[MCPServerSseParams] = [],
+        mcp_servers: Optional[list[MCPServerSseParams]] = None,
         *args, **kwargs):
         ...
-        # self.mcp_servers = mcp_servers
+        self.mcp_servers = mcp_servers or []
```

Now `handle_tool_init()` can safely look at `self.mcp_servers`.

---

### 4  Example “smoke test” with the Browserbase MCP server

```python
# examples/mcp_example/mcp_client.py
from swarms.structs.agent import Agent
from swarms.prompts.agent_prompts import MATH_AGENT_PROMPT
from swarms.tools.mcp_integration import MCPServerSseParams

browserbase = MCPServerSseParams(
    url="http://127.0.0.1:6274",          # running Browserbase MCP server
    headers={"Content-Type": "application/json"},
)

math_bot = Agent(
    agent_name="Math‑MCP‑Bot",
    agent_description="Performs arithmetic via MCP tools",
    system_prompt=MATH_AGENT_PROMPT,
    max_loops=1,
    mcp_servers=[browserbase],            # <-- now recognised
    output_type="final",
)

print(math_bot.run("Use the add tool to add 2 and 2"))
```

Make sure you’ve installed the SDK:

```bash
pip install "mcp>=0.3.0"  typing_extensions
```

and that the Browserbase server from the README snippet is running (or any
other MCP SSE server).

---

### 5  What to do *if* you really want “fastmcp”

There isn’t a published `fastmcp` Python package today (hence the
`ModuleNotFoundError`). Stick with the official `mcp` SDK until/if the
fast‑variant is released. When it lands the only changes you’d make are the
two import lines in **mcp_integration.py**; the rest of the Swarms integration
stays identical.

---

Apply those three code edits, reinstall dependencies, and your smoke test
should run without import errors. If you hit the next snag, drop the new
traceback and we’ll keep tightening the bolts.