Streaming - Anthid

Anthid provides real-time broker updates through gRPC streaming. While REST APIs are used for creating intents and querying historical data, the Streaming API delivers live order and position updates as they occur. Streaming allows applications to react immediately to broker activity without polling REST endpoints.

Availability

Streaming is available on all plans. Organizations may maintain multiple concurrent stream connections subject to plan limits. API-key connection limits are resolved from the organization’s billing limits.

Access

Streaming requests must be authenticated and associated with an organization. Client examples use the x-api-key gRPC metadata header. Subscriptions are scoped to trading accounts owned by the authenticated principal’s organization. Subscribe requests must include a valid trading account UUID and at least one event type.

Subscriptions

Once connected, your client can subscribe to message types for a trading account. The subscription messages are defined in protobuf via the proto repository: anthid-labs/proto.

Service Definition

service TradingService {
  rpc StreamEvents(stream StreamEventsRequest)
      returns (stream TradingEvent);

  rpc SubscribeEvents(Subscribe)
      returns (stream TradingEvent);
}

Streaming Models

Anthid supports two streaming patterns.

StreamEvents

A bidirectional gRPC stream intended for backend and native applications. Clients can dynamically subscribe and unsubscribe from trading accounts over an existing connection.

SubscribeEvents

A server-streaming endpoint intended for clients with a fixed subscription. The subscription is established when the request is created and remains active for the lifetime of the stream.

Endpoints

RPC	Request	Response	Use case
`StreamEvents`	Client stream of `StreamEventsRequest` messages	Server stream of `TradingEvent` messages	Dynamic subscribe and unsubscribe over one connection
`SubscribeEvents`	Single `Subscribe` message	Server stream of `TradingEvent` messages	One fixed account subscription per stream

Authentication

Streaming requests must include an API key using gRPC metadata.

x-api-key: YOUR_API_KEY

Event Types

Applications can subscribe to one or more event types.

Event Type	Description
EVENT_TYPE_BROKER_ORDER	Real-time order lifecycle updates
EVENT_TYPE_BROKER_POSITION	Real-time position updates

Subscription Requests

{
  "trading_account_id": "ACCOUNT_ID",
  "subscriptions": [
    "EVENT_TYPE_BROKER_ORDER",
    "EVENT_TYPE_BROKER_POSITION"
  ]
}

Unsubscribe

Unsubscribe is only available on the bidirectional StreamEvents RPC.

{
  "trading_account_id": "ACCOUNT_ID"
}

Stream Events

The server may emit the following event types.

Heartbeat

Indicates that the connection remains healthy. The server emits heartbeats approximately every 5 seconds.

Status

Returned when a subscription is added or removed successfully. Successful messages are subscribed and unsubscribed.

Error

Returned when a request cannot be processed.

BrokerOrder

Represents a real-time order lifecycle update. Events may include:

New orders
Accepted orders
Partial fills
Filled orders
Cancelled orders
Rejected orders

BrokerPosition

Represents a real-time position update received from a broker. Position updates are emitted whenever Anthid receives a change in account holdings. Broker trade events and internal broker heartbeat events are not forwarded on the public stream.

Connection Lifecycle

Connect to the streaming endpoint.
Authenticate using an API key.
Subscribe to one or more trading accounts.
Receive status confirmation.
Receive real-time events.
Reconnect and resubscribe if the connection is interrupted.

Streams are connection-oriented. If a stream closes, create a new stream and resubscribe to the required trading accounts.

Recommended Usage

Use the Streaming API for:

Live order monitoring
Position synchronization
Trading dashboards
Notifications
Automated trading workflows

Use REST APIs for:

Intent submission
Historical queries
Search and filtering
Reporting
Reconciliation workflows

Node.js Guide
Python Guide
Rust Guide
Intents
Orders
Positions
Trading Accounts
Ledger

Support

For questions about authentication, request formats, or API behavior, contact support@anthid.com.

​Availability

​Access

​Subscriptions

​Service Definition

​Streaming Models

​StreamEvents

​SubscribeEvents

​Endpoints

​Authentication

​Event Types

​Subscription Requests

​Subscribe

​Unsubscribe

​Stream Events

​Heartbeat

​Status

​Error

​BrokerOrder

​BrokerPosition

​Connection Lifecycle

​Recommended Usage

​Related Resources

​Support