> ## Documentation Index
> Fetch the complete documentation index at: https://fastmcp-docs-v3-beta2-feature-tracking.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# ping

# `fastmcp.server.middleware.ping`

Ping middleware for keeping client connections alive.

## Classes

### `PingMiddleware` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/middleware/ping.py#L10" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

Middleware that sends periodic pings to keep client connections alive.

Starts a background ping task on first message from each session. The task
sends server-to-client pings at the configured interval until the session
ends.

**Methods:**

#### `on_message` <sup><a href="https://github.com/jlowin/fastmcp/blob/main/src/fastmcp/server/middleware/ping.py#L42" target="_blank"><Icon icon="github" style="width: 14px; height: 14px;" /></a></sup>

```python theme={null}
on_message(self, context: MiddlewareContext, call_next: CallNext) -> Any
```

Start ping task on first message from a session.