# WebSocket /route/subscribe

> The WebSocket protocol of /route/subscribe: live DEX Aggregator quotes that update whenever NEAR pools change.

This page is part of the DEX Aggregator docs. The aggregator is at `https://router.intear.tech`, with live quotes at `wss://router.intear.tech/route/subscribe`, on NEAR mainnet only. https://docs.intear.tech/dex-aggregator/llms-full.txt has all of its pages in one file, and https://docs.intear.tech/llms.txt lists every page of the Intear docs.

```
wss://router.intear.tech/route/subscribe
```

A WebSocket that sends quotes for a request and keeps sending new ones as pools change. See [Live quotes](https://docs.intear.tech/dex-aggregator/guides/live-quotes.md) for a walkthrough.

## Connection

All messages are JSON in text frames. Non-text frames from the client are ignored. Add `?key=<api key>` to the URL to lift the [rate limit](https://docs.intear.tech/dex-aggregator/reference/errors.md#rate-limits).

The server never sends a WebSocket close frame, so clients see every close, including one they start, as abnormal (code `1006`). Don't use the close code to tell why a connection ended.

## Client messages

```json
{ "id": 1, "query": "token_in=near&token_out=nep141:usdt.tether-token.near&amount_in=1000000000000000000000000&slippage_type=Fixed&slippage=0.01" }
```

| Field | Type | Description |
| --- | --- | --- |
| `id` | unsigned integer | Your ID for this request, sent back with each update |
| `query` | string, optional | Same query string as [`GET /route`](https://docs.intear.tech/dex-aggregator/reference/route.md#query-parameters). If missing, the current request is stopped and nothing new starts |

Each message replaces the previous request. A message that isn't valid JSON of this shape, including one whose `id` is negative, fractional, a string or missing, makes the server drop the connection.

## Server messages

Quotes for a request:

```json
{ "id": 1, "routes": [ ... ] }
```

`routes` is an array of [quote objects](https://docs.intear.tech/dex-aggregator/reference/quote.md), best first, same as `GET /route`. The first update is sent after the first round of routing, with an empty `routes` array if no DEX found a route. After that, one is sent each time pools update and the quotes change.

An error for a request:

```json
{ "id": 1, "error": "Slippage must be between 0.00 and 1.00" }
```

Sent instead of quotes when the query is invalid. The connection stays open. Validation errors have the same text as for [`GET /route`](https://docs.intear.tech/dex-aggregator/reference/errors.md). Errors in parsing the query string come without the `Failed to deserialize query string: ` prefix and the parameter name, like ``missing field `token_in` `` or `Empty dex id`.

## Timing

After each round of routing, the server waits until about 10× the routing time has passed since the round started, at most 3 seconds. Then it routes again as soon as any pool has changed since the round started. In practice this means an update every block or every few blocks while the pools are active.