How to: Monitoring a TCP endpoint
By prefixing `endpoints[].url` with `tcp://`, you can monitor TCP endpoints at a very basic level:
```yaml
endpoints:
  - name: redis
    url: "tcp://127.0.0.1:6379"
    interval: 30s
    conditions:
      - "[CONNECTED] == true"
```
If `endpoints[].body` is set then it is sent and the first 1024 bytes of the response will be in `[BODY]`.

Placeholder `[STATUS]` as well as the fields `endpoints[].headers`,
`endpoints[].method` and `endpoints[].graphql` are not supported for TCP endpoints.

This works for applications such as databases (Postgres, MySQL, etc.) and caches (Redis, Memcached, etc.).

> 📝 `[CONNECTED] == true` does not guarantee that the endpoint itself is healthy - it only guarantees that there's
> something at the given address listening to the given port, and that a connection to that address was successfully
> established.