MMT API Best Practices

Rules for building reliable, performant applications with the MMT market data API.

Connection Management

• WebSocket Lifecycle: connect/disconnect flow, heartbeat, connection states, cleanup
• Authentication: API key via header (REST) vs query param (WS), server-side proxy for browser apps
• Reconnection Strategy: exponential backoff, resubscription, state recovery

Rate Limiting

• Weight Management: weight costs per endpoint, budget allocation, monitoring
• Tier Awareness: Strict/Standard/Premium limits, feature gating
• Burst Strategy: burst bucket mechanics, pre-flight checks, graceful degradation

Data Handling

• CBOR Optimization: when and how to use CBOR, bandwidth savings, decoding
• Symbol Normalization: base/quote format, /markets discovery, inverse contracts
• Timeframe Rules: validation rules, calendar timeframes, UTC alignment
• Type Handling: public type field maps for all data types

WebSocket

• Subscription Management: sub/unsub protocol, limits, deduplication
• Range Requests: historical data via WS, from/to params
• Channel Selection: channel guide and when to use each

REST API

• Endpoint Selection: endpoint decision tree, parameter reference
• Caching Strategy: cache /markets, TTLs, ETag patterns
• Timeframe Alignment: UTC boundary alignment, candle close semantics

Multi-Exchange Aggregation

• Multi-Exchange Queries: colon-separated syntax, supported endpoints
• Cost Optimization: weight multipliers, tier restrictions

Error Handling

• Error Patterns: error code reference, structured format, recovery
• Retry Strategy: retryable vs non-retryable, backoff, circuit breaker

Performance

• Memory & Batching: batch fetches, stream processing, avoid unbounded buffers