The clob.* channels carry the Polymarket CLOB (central limit order book) live feed. Radion proxies it over the same WebSocket as the on-chain channels, so you get order-book state, prices, and trades next to the confirmed chain events, on one connection.
This is a separate channel family from the topic channels (trading, positions, and the rest). It differs in three ways:
- Every clob channel requires a
token_ids filter. You subscribe per outcome token. With no token_ids, the subscribe fails.
- The
data payload has no type discriminator. Each clob channel has one fixed payload shape. Topic channels put a snake_case type inside data; clob channels do not.
- There is no pending feed. CLOB channels have no pending/confirmed concept —
confirmed: false does not apply. The CLOB feed is off-chain order-book state, not pending transactions.
Channels
| Channel | Sends |
|---|
clob.book | Full order-book snapshot: all bid and ask levels. |
clob.prices | Price-change batches: which levels moved, and the new best bid/ask. |
clob.last_trade | The last trade price and size for the token. |
clob.midpoint | The midpoint between best bid and best ask. |
clob.tick_size | Tick-size changes for the token. |
clob.best_bid_ask | The best bid and best ask. |
clob.prices is the CLOB price-change feed. It is not the removed derived
prices topic channel — that one carried last-trade price ticks and no longer
exists. clob.prices is unrelated and stays.
Subscribe
Every clob channel requires at least one token_ids value:
{
"action": "subscribe",
"id": "s1",
"channel": "clob.book",
"filters": {
"token_ids": [
"71321045679252212594626385532706912750332728571942532289631379312455583992563"
]
}
}
Filters
| Filter | Type | Required | Description |
|---|
token_ids | string[] | Yes | Outcome token IDs as decimal strings. At least one, or the subscribe fails. |
token_ids. wallets, market_ids, and min_usd are ignored here. See Filters for the combination rule.
Payloads
Each frame is a standard event frame: type: "event", your id, the channel name, and a data object. Unlike the topic channels, data carries no type field — the channel name already tells you the shape.
In every payload, ids are strings (asset_id is a U256 decimal string, market is a 0x hex string), timestamp is a number, and prices and sizes are numbers. Fields marked optional may be absent.
clob.book
Full order-book snapshot for the token.
{
"type": "event",
"id": "s1",
"channel": "clob.book",
"data": {
"asset_id": "71321045…992563",
"market": "0x…",
"timestamp": 1730000000,
"bids": [{ "price": 0.52, "size": 1200 }],
"asks": [{ "price": 0.54, "size": 800 }]
}
}
| Field | Type | Description |
|---|
asset_id | string | Outcome token id (U256 decimal string). |
market | string | Market id (0x hex string). |
timestamp | number | Feed timestamp. |
bids | Level[] | Bid levels. Each Level is { price, size } (numbers). |
asks | Level[] | Ask levels. Each Level is { price, size } (numbers). |
clob.prices
A batch of level changes for a market, with the new best bid/ask per token.
{
"type": "event",
"id": "s1",
"channel": "clob.prices",
"data": {
"market": "0x…",
"timestamp": 1730000000,
"changes": [
{
"asset_id": "71321045…992563",
"price": 0.53,
"size": 500,
"best_bid": 0.52,
"best_ask": 0.54
}
]
}
}
| Field | Type | Description |
|---|
market | string | Market id (0x hex string). |
timestamp | number | Feed timestamp. |
changes | PriceChange[] | The changed levels. See below. |
PriceChange:
| Field | Type | Optional | Description |
|---|
asset_id | string | No | Outcome token id. |
price | number | No | The changed price level. |
size | number | Yes | New size at the level. |
best_bid | number | Yes | New best bid for the token. |
best_ask | number | Yes | New best ask for the token. |
clob.last_trade
The last trade for the token.
{
"type": "event",
"id": "s1",
"channel": "clob.last_trade",
"data": {
"asset_id": "71321045…992563",
"market": "0x…",
"price": 0.53,
"size": 250,
"timestamp": 1730000000
}
}
| Field | Type | Optional | Description |
|---|
asset_id | string | No | Outcome token id. |
market | string | No | Market id (0x hex string). |
price | number | No | Last trade price. |
size | number | Yes | Last trade size. |
timestamp | number | No | Feed timestamp. |
clob.midpoint
The midpoint between best bid and best ask.
{
"type": "event",
"id": "s1",
"channel": "clob.midpoint",
"data": {
"asset_id": "71321045…992563",
"market": "0x…",
"midpoint": 0.53,
"timestamp": 1730000000
}
}
| Field | Type | Description |
|---|
asset_id | string | Outcome token id. |
market | string | Market id (0x hex string). |
midpoint | number | Midpoint price. |
timestamp | number | Feed timestamp. |
clob.tick_size
A tick-size change for the token.
{
"type": "event",
"id": "s1",
"channel": "clob.tick_size",
"data": {
"asset_id": "71321045…992563",
"market": "0x…",
"timestamp": 1730000000
}
}
| Field | Type | Description |
|---|
asset_id | string | Outcome token id. |
market | string | Market id (0x hex string). |
timestamp | number | Feed timestamp. |
clob.best_bid_ask
The best bid and best ask for the token.
{
"type": "event",
"id": "s1",
"channel": "clob.best_bid_ask",
"data": {
"asset_id": "71321045…992563",
"market": "0x…",
"best_bid": 0.52,
"best_ask": 0.54,
"timestamp": 1730000000
}
}
| Field | Type | Description |
|---|
asset_id | string | Outcome token id. |
market | string | Market id (0x hex string). |
best_bid | number | Best bid price. |
best_ask | number | Best ask price. |
timestamp | number | Feed timestamp. |
No pending feed
Clob channels have no pending/confirmed concept — confirmed: false does not apply. The pending feed streams pending on-chain transactions; the CLOB feed is off-chain order-book state, so there is nothing to mirror. See Mempool for the channels that do have a pending feed.