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Messages
{
"action": "subscribe",
"platform": "polymarket",
"version": 1,
"type": "orderbook",
"filters": {
"market_slugs": [
"bitcoin-100k-2026"
]
}
}{
"action": "unsubscribe",
"subscription_id": "sub_2f4b15b33798"
}{
"type": "ack",
"subscription_id": "sub_2f4b15b33798",
"channel": "trades"
}{
"event_type": "book_snapshot",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"question": "Will Bitcoin hit $100k?",
"outcome": "Yes",
"timestamp": 1775196804071,
"bids": [
{
"price": "0.48",
"size": "5000"
}
],
"asks": [
{
"price": "0.52",
"size": "3000"
}
],
"hash": "abc123..."
}{
"event_type": "price_change",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196805000,
"side": "BUY",
"price": "0.50",
"size": "7500",
"best_bid": "0.50",
"best_ask": "0.52"
}{
"event_type": "last_trade",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196806000,
"side": "BUY",
"price": "0.46",
"size": "219.22",
"fee_rate_bps": "0"
}{
"event_type": "tick_size_change",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196807000,
"tick_size": "0.001"
}{
"event_type": "snapshots_done",
"count": 2
}{
"type": "event_batch",
"subscription_id": "sub_xxx",
"count": 350,
"events": [],
"gap": false
}{
"event_type": "resync"
}Playground
Orderbook Playground
WSS
Messages
{
"action": "subscribe",
"platform": "polymarket",
"version": 1,
"type": "orderbook",
"filters": {
"market_slugs": [
"bitcoin-100k-2026"
]
}
}{
"action": "unsubscribe",
"subscription_id": "sub_2f4b15b33798"
}{
"type": "ack",
"subscription_id": "sub_2f4b15b33798",
"channel": "trades"
}{
"event_type": "book_snapshot",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"question": "Will Bitcoin hit $100k?",
"outcome": "Yes",
"timestamp": 1775196804071,
"bids": [
{
"price": "0.48",
"size": "5000"
}
],
"asks": [
{
"price": "0.52",
"size": "3000"
}
],
"hash": "abc123..."
}{
"event_type": "price_change",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196805000,
"side": "BUY",
"price": "0.50",
"size": "7500",
"best_bid": "0.50",
"best_ask": "0.52"
}{
"event_type": "last_trade",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196806000,
"side": "BUY",
"price": "0.46",
"size": "219.22",
"fee_rate_bps": "0"
}{
"event_type": "tick_size_change",
"token_id": "82855...",
"condition_id": "0x4c57...",
"slug": "bitcoin-100k-2026",
"outcome": "Yes",
"timestamp": 1775196807000,
"tick_size": "0.001"
}{
"event_type": "snapshots_done",
"count": 2
}{
"type": "event_batch",
"subscription_id": "sub_xxx",
"count": 350,
"events": [],
"gap": false
}{
"event_type": "resync"
}api_key
type:httpApiKey
Your Predexon API key
Subscribe to Orderbook
type:object
Exactly ONE of token_ids, condition_ids, or market_slugs. No users filter.
Unsubscribe
type:object
Remove a subscription by ID.
Acknowledgement
type:object
Server acknowledgement for subscribe, unsubscribe, and update actions.
Book Snapshot
type:object
Full orderbook snapshot sent on subscribe.
Price Change
type:object
Orderbook price level delta. Size '0' means level removed.
Last Trade
type:object
Trade execution on the orderbook channel.
Tick Size Change
type:object
Emitted when a market's tick size changes.
Snapshots Done
type:object
Marker sent after all initial book snapshots have been delivered.
Event Batch
type:object
Wildcard/firehose only. Batched every ~250ms with price-level conflation.
Resync
type:object
Sent after internal reconnect. Discard local state — fresh snapshots will follow.
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