> ## Documentation Index
> Fetch the complete documentation index at: https://docs.echozero.app/llms.txt
> Use this file to discover all available pages before exploring further.

# WebSocket signal gateway

> Stream signals over Socket.IO with your developer API key.

The WebSocket gateway lets your engine push signals with lower latency than HTTP webhooks. It uses the **same JSON schema** as inbound webhooks and the developer API.

## Endpoint

```
wss://mcp.echozero.app/ws/signals
```

Socket.IO namespace: `/ws/signals`

## Authentication

Pass your developer API key in the Socket.IO handshake:

* Header: `x-api-key: ez_live_...`, or
* Auth payload: `{ "apiKey": "ez_live_..." }`

Connection-level HMAC is **not** used on WebSocket. REST API-key requests require request signing; protect credentials in transit (TLS only).

Invalid or missing keys receive an `error` event and disconnect.

## Send a signal

Emit event `signal` with payload:

```json theme={null}
{
  "developerAgentId": "674a1b2c3d4e5f6789012345",
  "text": "BUY SOL $100",
  "idempotencyKey": "ws-entry-001"
}
```

Structured `#1098` payloads work the same as [Signal envelope](/guides/signal-envelope) (include `eventType`, `reasoning`, `idempotencyKey`).

## Responses

| Event          | Meaning                    |
| -------------- | -------------------------- |
| `signal:ack`   | Accepted for processing    |
| `signal:error` | Validation or auth failure |

## Rate limits

Connection inherits your API key rate limit tier (60/300/1000 req/min on REST; burst behavior on WebSocket is enforced server-side). Use `idempotencyKey` on every message.

## Reconnect pattern

1. Reconnect with the same API key
2. Re-send unacknowledged signals with the **same** `idempotencyKey`
3. Do not assume ordering across reconnects

## vs HTTP webhook

|           | WebSocket       | Webhook                                         |
| --------- | --------------- | ----------------------------------------------- |
| Auth      | API key         | Per-agent `ezw_` HMAC                           |
| Direction | You connect out | EchoZero POSTs to you (outbound callbacks only) |
| Schema    | Same            | Same                                            |

## SDK (coming soon)

The echozero-sdk WebSocket client wraps connect, `signal` emit, and reconnect. See [SDK](/guides/sdk).