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

# gRPC API Types

# gRPC API

The agent communicates with the Silvana orderbook server via 4 gRPC services defined in `proto/silvana/*/v1/*.proto`.

| **Service**           | **Proto**                        | **Role**                                                                      | **Streaming**                                                                                        |
| :-------------------- | :------------------------------- | :---------------------------------------------------------------------------- | :--------------------------------------------------------------------------------------------------- |
| `DAppProviderService` | `ledger/v1/*.proto`              | Two-phase <br />transaction signing, <br />balance and <br />contract queries | Server-streaming <br />(`GetActiveContracts`, <br />`GetUpdates`)                                    |
| `SettlementService`   | `settlement/v1/settlement.proto` | DVP settlement <br />orchestration, <br />RFQ handling                        | Bidirectional <br />(`SettlementStream`)                                                             |
| `OrderbookService`    | `orderbook/v1/orderbook.proto`   | Order submission, <br />market data, <br />RFQ initiation                     | Server-streaming <br />(`SubscribeOrderbook`, <br />`SubscribeOrders`, <br />`SubscribeSettlements`) |
| `PricingService`      | `pricing/v1/pricing.proto`       | External price <br />feeds (Binance, <br />ByBit, CoinGecko)                  | Server-streaming <br />(`StreamPrices`)                                                              |

<Check>
  Access gRPC APIs below.
</Check>

<CardGroup cols={2}>
  <Card title="Execution API" href="/sdk/grpc-api/execution-api">
    Place orders and execute trades.
  </Card>

  <Card title="Pricing API" href="/sdk/grpc-api/pricing-api">
    Get live and historical prices.
  </Card>

  <Card title="Settlement API" href="/sdk/grpc-api/settlement-api">
    Track and manage trade settlement.
  </Card>

  <Card title="Ledger Gateway API" href="/sdk/grpc-api/ledger-gateway-api">
    Query the ledger and submit txs.
  </Card>
</CardGroup>