# HTTP API

A Lighthouse beacon node can be configured to expose a HTTP server by supplying the `--http` flag. The default listen address is `localhost:5052`.

The following CLI flags control the HTTP server:

- `--http`: enable the HTTP server (required even if the following flags are
	provided).
- `--http-port`: specify the listen port of the server.
- `--http-address`: specify the listen address of the server.

The API is logically divided into several core endpoints, each documented in
detail:

Endpoint | Description |
| --- | -- |
[`/node`](./http/node.md) | General information about the beacon node.
[`/beacon`](./http/beacon.md) | General information about the beacon chain.
[`/validator`](./http/validator.md) | Provides functionality to validator clients.
[`/consensus`](./http/consensus.md) | Proof-of-stake voting statistics.
[`/network`](./http/network.md) | Information about the p2p network.
[`/spec`](./http/spec.md) | Information about the specs that the client is running.
[`/advanced`](./http/advanced.md) | Provides endpoints for advanced inspection of Lighthouse specific objects.
[`/lighthouse`](./http/lighthouse.md) | Provides lighthouse specific endpoints.

_Please note: The OpenAPI format at
[SwaggerHub: Lighthouse REST
API](https://app.swaggerhub.com/apis-docs/spble/lighthouse_rest_api/0.2.0) has
been **deprecated**. This documentation is now the source of truth for the REST API._

## Troubleshooting

### HTTP API is unavailable or refusing connections

Ensure the `--http` flag has been supplied at the CLI.

You can quickly check that the HTTP endpoint is up using `curl`:

```
curl "localhost:5052/beacon/head"

{"slot":37934,"block_root":"0x4d3ae7ebe8c6ef042db05958ec76e8f7be9d412a67a0defa6420a677249afdc7","state_root":"0x1c86b13ffc70a41e410eccce20d33f1fe59d148585ea27c2afb4060f75fe6be2","finalized_slot":37856,"finalized_block_root":"0xbdae152b62acef1e5c332697567d2b89e358628790b8273729096da670b23e86","justified_slot":37888,"justified_block_root":"0x01c2f516a407d8fdda23cad4ed4381e4ab8913d638f935a2fe9bd00d6ced5ec4","previous_justified_slot":37856,"previous_justified_block_root":"0xbdae152b62acef1e5c332697567d2b89e358628790b8273729096da670b23e86"}
```