> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hypedexer.com/llms.txt
> Use this file to discover all available pages before exploring further.

# l2Book

> L2 order book: snapshot then book deltas for one coin

Subscribe with `{"method":"subscribe","subscription":{"type":"l2Book","coin":"BTC"}}`. Initial book matches **`L2BookSnapshot`**; incremental updates use **`L2BookUpdate`**.


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