---
title: low_level
sidebarTitle: low_level
---

# `fastmcp.server.low_level`

## Classes

### `MiddlewareServerSession` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L33" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>


ServerSession that routes initialization requests through FastMCP middleware.


**Methods:**

#### `fastmcp` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L43" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
fastmcp(self) -> FastMCP
```

Get the FastMCP instance.


### `LowLevelServer` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L130" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

**Methods:**

#### `fastmcp` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L144" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
fastmcp(self) -> FastMCP
```

Get the FastMCP instance.


#### `create_initialization_options` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L151" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
create_initialization_options(self, notification_options: NotificationOptions | None = None, experimental_capabilities: dict[str, dict[str, Any]] | None = None, **kwargs: Any) -> InitializationOptions
```

#### `run` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/low_level.py#L166" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python
run(self, read_stream: MemoryObjectReceiveStream[SessionMessage | Exception], write_stream: MemoryObjectSendStream[SessionMessage], initialization_options: InitializationOptions, raise_exceptions: bool = False, stateless: bool = False)
```

Overrides the run method to use the MiddlewareServerSession.

