---
title: client
sidebarTitle: client
---

# `fastmcp.client.client`

## Classes

### `Client`



    MCP client that delegates connection management to a Transport instance.

    The Client class is responsible for MCP protocol logic, while the Transport
    handles connection establishment and management. Client provides methods for
    working with resources, prompts, tools and other MCP capabilities.

    Args:
        transport: Connection source specification, which can be:
            - ClientTransport: Direct transport instance
            - FastMCP: In-process FastMCP server
            - AnyUrl | str: URL to connect to
            - Path: File path for local socket
            - MCPConfig: MCP server configuration
            - dict: Transport configuration
        roots: Optional RootsList or RootsHandler for filesystem access
        sampling_handler: Optional handler for sampling requests
        log_handler: Optional handler for log messages
        message_handler: Optional handler for protocol messages
        progress_handler: Optional handler for progress notifications
        timeout: Optional timeout for requests (seconds or timedelta)
        init_timeout: Optional timeout for initial connection (seconds or timedelta).
            Set to 0 to disable. If None, uses the value in the FastMCP global settings.

    Examples:
        ```python # Connect to FastMCP server client =
        Client("http://localhost:8080")

        async with client:
            # List available resources resources = await client.list_resources()

            # Call a tool result = await client.call_tool("my_tool", {"param":
            "value"})
        ```
    

**Methods:**

#### `session`

```python
session(self) -> ClientSession
```

Get the current active session. Raises RuntimeError if not connected.


#### `initialize_result`

```python
initialize_result(self) -> mcp.types.InitializeResult
```

Get the result of the initialization request.


#### `set_roots`

```python
set_roots(self, roots: RootsList | RootsHandler) -> None
```

Set the roots for the client. This does not automatically call `send_roots_list_changed`.


#### `set_sampling_callback`

```python
set_sampling_callback(self, sampling_callback: SamplingHandler) -> None
```

Set the sampling callback for the client.


#### `is_connected`

```python
is_connected(self) -> bool
```

Check if the client is currently connected.

