> ## Documentation Index > Fetch the complete documentation index at: https://docs.arcus.xyz/llms.txt > Use this file to discover all available pages before exploring further. # Markets > > **Endpoint:** `wss://api.testnet.arcus.xyz/v1/ws` — one socket multiplexes every channel and RPC request. Click **Connect**, then send the example subscribe message below to start receiving data. Global channel — no `id` required. Streams full per-market metadata for all listed markets. Snapshot-only channel: every message is a full map of all markets keyed by `marketId` (same shape on subscribe and on every periodic re-emission, no partial diffs). Clients replace their entire markets view on each message. **Cadence:** ~5s periodic snapshot, plus an immediate snapshot when a new funding rate is applied (~hourly) so the just-applied `fundingRate` propagates without waiting for the next periodic snapshot. **Field coverage today:** `marketDisplayName`, `marketId`, `baseAsset`, `quoteAsset`, `status` (always `ONLINE` today — dynamic state changes not yet plumbed), static config (tick/step/min/max sizes, margin fractions, fees), `oraclePrice`, `fundingRate`, `nextFundingRate`, and `nextFundingAt` are populated. `priceChange24h`, `volume24h`, and `trades24h` are populated by the rolling-24h aggregator (in-memory ring of the last 1440 closed 1m candles per market, plus the in-progress 1m candle from Redis) and refresh every ~10s. `openInterest` is the total size of all open long positions per market (equals total short), in base asset units, refreshed from a periodic snapshot (default ~60s) so it may lag real time. ## AsyncAPI ````yaml api-reference/asyncapi.yaml markets id: markets title: Markets description: > > **Endpoint:** `wss://api.testnet.arcus.xyz/v1/ws` — one socket multiplexes every channel and RPC request. Click **Connect**, then send the example subscribe message below to start receiving data. Global channel — no `id` required. Streams full per-market metadata for all listed markets. Snapshot-only channel: every message is a full map of all markets keyed by `marketId` (same shape on subscribe and on every periodic re-emission, no partial diffs). Clients replace their entire markets view on each message. **Cadence:** ~5s periodic snapshot, plus an immediate snapshot when a new funding rate is applied (~hourly) so the just-applied `fundingRate` propagates without waiting for the next periodic snapshot. **Field coverage today:** `marketDisplayName`, `marketId`, `baseAsset`, `quoteAsset`, `status` (always `ONLINE` today — dynamic state changes not yet plumbed), static config (tick/step/min/max sizes, margin fractions, fees), `oraclePrice`, `fundingRate`, `nextFundingRate`, and `nextFundingAt` are populated. `priceChange24h`, `volume24h`, and `trades24h` are populated by the rolling-24h aggregator (in-memory ring of the last 1440 closed 1m candles per market, plus the in-progress 1m candle from Redis) and refresh every ~10s. `openInterest` is the total size of all open long positions per market (equals total short), in base asset units, refreshed from a periodic snapshot (default ~60s) so it may lag real time. servers: - id: testnet protocol: wss host: api.testnet.arcus.xyz bindings: [] variables: [] - id: mainnet protocol: wss host: api.arcus.xyz bindings: [] variables: [] address: /v1/ws?channel=markets parameters: [] bindings: [] operations: - &ref_3 id: subscribeMarkets title: Subscribe markets type: receive messages: - &ref_5 id: subscribe contentType: application/json payload: - name: Subscribe to the markets channel type: object properties: - name: type type: string description: subscribe required: true - name: channel type: string enumValues: - markets - exchangeAttributeUpdates required: true headers: [] jsonPayloadSchema: type: object required: - type - channel properties: type: type: string const: subscribe x-parser-schema-id: channel: type: string enum: - markets - exchangeAttributeUpdates x-parser-schema-id: x-parser-schema-id: SubscribeGlobalPayload title: Subscribe to the markets channel example: |- { "type": "subscribe", "channel": "markets" } bindings: [] extensions: - id: x-parser-unique-object-id value: subscribe bindings: [] extensions: &ref_2 - id: x-parser-unique-object-id value: markets - &ref_4 id: receiveMarkets title: Receive markets type: send messages: - &ref_6 id: snapshot contentType: application/json payload: - allOf: &ref_0 - type: object description: Common envelope for all server-pushed channel messages. required: - type - channel properties: type: type: string enum: - subscribed - channel_data description: >- `subscribed` for the initial snapshot; `channel_data` for updates. x-parser-schema-id: channel: type: string description: Channel name. x-parser-schema-id: id: type: string description: >- Channel id (market or address). Absent for global channels. x-parser-schema-id: contents: type: object additionalProperties: true description: Channel-specific payload. Schema varies by channel. properties: {} x-parser-schema-id: x-parser-schema-id: ChannelDataEnvelope - type: object properties: contents: type: object required: - isSnapshot - markets properties: isSnapshot: type: boolean description: > Always `true` on this channel — every emission is a full snapshot, not a partial diff. example: true x-parser-schema-id: markets: type: object description: > All markets keyed by `marketId` as a string. Same per-market shape as REST `GET /v1/markets` (`MarketInfo`). additionalProperties: type: object description: One market entry. Matches REST `MarketInfo`. properties: marketDisplayName: type: string example: BTC-USD x-parser-schema-id: marketId: type: integer example: 0 x-parser-schema-id: status: type: string example: ONLINE x-parser-schema-id: baseAsset: type: string example: BTC x-parser-schema-id: quoteAsset: type: string example: USD x-parser-schema-id: tickSize: type: string x-parser-schema-id: stepSize: type: string x-parser-schema-id: oraclePrice: type: string example: '94500.00' x-parser-schema-id: fundingRate: type: string description: Most recently applied funding rate. example: '0.0001' x-parser-schema-id: nextFundingRate: type: string description: >- In-progress forecast for the next funding payment. example: '0.00012' x-parser-schema-id: nextFundingAt: type: integer format: int64 description: Unix seconds for the next funding payment time. x-parser-schema-id: priceChange24h: type: string description: >- Reserved — returns "0" until 24h aggregator is wired. x-parser-schema-id: volume24h: type: string description: >- Reserved — returns "0" until 24h aggregator is wired. x-parser-schema-id: trades24h: type: integer format: int64 description: >- Reserved — returns 0 until 24h aggregator is wired. x-parser-schema-id: openInterest: type: string description: >- Total size of all open long positions in the market (equals total short), in base asset units. Refreshed from a periodic snapshot, so it may lag real time. x-parser-schema-id: initialMarginFraction: type: string x-parser-schema-id: maintenanceMarginFraction: type: string x-parser-schema-id: offHoursInitialMarginFraction: type: string description: >- Initial margin fraction the engine enforces outside `regularTradingHours` (overnight/weekends for equity-class markets); equals `initialMarginFraction` for 24/7 markets. Maintenance margin is not uplifted off-hours. x-parser-schema-id: currentSettlementPrice: type: string description: >- Sealed VWAP settlement price (decimal USD) anchoring the off-hours trading band. Present only while outside RTH with a sealed anchor; omitted in-RTH and for 24/7 markets. x-parser-schema-id: currentTradingBound: type: string description: >- Off-hours trading-band multiplier in force as a decimal string ("0.5"/"1"/"2"/"4"). Present only while outside RTH with a sealed anchor; omitted in-RTH and for 24/7 markets. x-parser-schema-id: nextTradingBound: type: string description: >- The next wider off-hours trading-band multiplier the market can expand to, one level above currentTradingBound on the fixed "0.5"→"1"→"2"→"4" ladder. Always differs from currentTradingBound except at the "4" maximum (no wider band). Present only while outside RTH with a sealed anchor. x-parser-schema-id: regularTradingHours: type: object description: >- Session window during which the base margin fractions apply; outside it the off-hours fractions apply. Omitted for 24/7 markets (crypto). properties: startSecondsOfDay: type: integer format: int32 x-parser-schema-id: endSecondsOfDay: type: integer format: int32 x-parser-schema-id: timezone: type: string example: America/New_York x-parser-schema-id: isOvernight: type: boolean x-parser-schema-id: x-parser-schema-id: type: type: string example: PERPETUAL x-parser-schema-id: assetResolution: type: string x-parser-schema-id: pythId: type: string x-parser-schema-id: x-parser-schema-id: properties: {} x-parser-schema-id: x-parser-schema-id: x-parser-schema-id: x-parser-schema-id: MarketsUpdatePayload name: Markets Snapshot description: > Full markets state delivered as the subscribe response. Same shape as the periodic `MarketsUpdate` — the markets channel is snapshot-only. headers: [] jsonPayloadSchema: &ref_1 allOf: *ref_0 x-parser-schema-id: MarketsUpdatePayload title: Markets Snapshot description: > Full markets state delivered as the subscribe response. Same shape as the periodic `MarketsUpdate` — the markets channel is snapshot-only. example: '{}' bindings: [] extensions: - id: x-parser-unique-object-id value: snapshot - &ref_7 id: update contentType: application/json payload: - allOf: *ref_0 x-parser-schema-id: MarketsUpdatePayload name: Markets Update description: > Periodic re-snapshot of all markets. Replaces the client's full markets view; there are no partial diffs on this channel. headers: [] jsonPayloadSchema: *ref_1 title: Markets Update description: > Periodic re-snapshot of all markets. Replaces the client's full markets view; there are no partial diffs on this channel. example: |- { "type": "channel_data", "channel": "markets", "contents": { "isSnapshot": true, "markets": { "0": { "marketDisplayName": "BTC-USD", "marketId": 1, "status": "ONLINE", "baseAsset": "BTC", "quoteAsset": "USD", "tickSize": "0.01", "stepSize": "0.0001", "minOrderSize": "0.0001", "oraclePrice": "94500.00", "fundingRate": "0.0001", "nextFundingRate": "0.00012", "nextFundingAt": 1712349600, "priceChange24h": "0.025", "volume24h": "1234.5678", "trades24h": 4242, "openInterest": "312.4567", "initialMarginFraction": "0.05", "maintenanceMarginFraction": "0.03", "type": "PERPETUAL" }, "1": { "marketDisplayName": "ETH-USD", "marketId": 1, "status": "ONLINE", "baseAsset": "ETH", "quoteAsset": "USD", "oraclePrice": "3050.00", "fundingRate": "0.00005", "nextFundingRate": "0.00007", "nextFundingAt": 1712349600, "type": "PERPETUAL" } } } } bindings: [] extensions: - id: x-parser-unique-object-id value: update bindings: [] extensions: *ref_2 sendOperations: - *ref_3 receiveOperations: - *ref_4 sendMessages: - *ref_5 receiveMessages: - *ref_6 - *ref_7 extensions: - id: x-parser-unique-object-id value: markets securitySchemes: [] ````