Stream Events

beta.sessions.events.stream(session_id, **kwargs) -> BetaManagedAgentsStreamSessionEvents

GET/v1/sessions/{session_id}/events/stream

Stream Events

Parameters

session_id: String

event_deltas: Array[BetaManagedAgentsDeltaType]

When set, this connection also receives streaming deltas (event_start, event_delta) while an event is being produced, before the event itself arrives. Deltas are best-effort; when the final event is produced it carries the complete content. A model request that ends early (an error or interrupt) produces no final event — its terminal span.model_request_end closes the preview. Accepts one or more event types to preview and may be repeated: agent.message streams content_delta fragments; agent.thinking is start-only — a signal that the agent has begun extended thinking, concluded by the agent.thinking event itself. Only previews of the requested event types are sent.

One of the following:

:"agent.message"

:"agent.thinking"

betas: Array[AnthropicBeta]

Optional header to specify the beta version(s) you want to use.

One of the following:

String = String

AnthropicBeta = :"message-batches-2024-09-24" | :"prompt-caching-2024-07-31" | :"computer-use-2024-10-22" | 38 more

One of the following:

:"message-batches-2024-09-24"

:"prompt-caching-2024-07-31"

:"computer-use-2024-10-22"

:"computer-use-2025-01-24"

:"pdfs-2024-09-25"

:"token-counting-2024-11-01"

:"token-efficient-tools-2025-02-19"

:"output-128k-2025-02-19"

:"files-api-2025-04-14"

:"mcp-client-2025-04-04"

:"mcp-client-2025-11-20"

:"dev-full-thinking-2025-05-14"

:"interleaved-thinking-2025-05-14"

:"code-execution-2025-05-22"

:"extended-cache-ttl-2025-04-11"

:"context-1m-2025-08-07"

:"context-management-2025-06-27"

:"model-context-window-exceeded-2025-08-26"

:"skills-2025-10-02"

:"fast-mode-2026-02-01"

:"output-300k-2026-03-24"

:"user-profiles-2026-03-24"

:"user-profiles-2026-08-18"

:"advisor-tool-2026-03-01"

:"managed-agents-2026-04-01"

:"cache-diagnosis-2026-04-07"

:"dreaming-2026-04-21"

:"thinking-token-count-2026-05-13"

:"server-side-fallback-2026-06-01"

:"server-side-fallback-2026-07-01"

:"fallback-credit-2026-06-01"

:"fallback-credit-2026-07-01"

:"agent-memory-2026-07-22"

:"mid-conversation-tool-changes-2026-07-01"

:"compact-2026-01-12"

:"computer-use-2025-11-24"

:"mcp-tunnels-2026-06-22"

:"structured-outputs-2025-11-13"

:"task-budgets-2026-03-13"

:"thinking-display-updates-2026-08-18"

:"ce-user-management-2026-07-13"

Returns

BetaManagedAgentsStreamSessionEvents = BetaManagedAgentsUserMessageEvent { id, content, type, processed_at } | BetaManagedAgentsUserInterruptEvent { id, type, processed_at, session_thread_id } | BetaManagedAgentsUserToolConfirmationEvent { id, result, tool_use_id, 4 more } | 34 more

Server-sent event in the session stream.

One of the following:

Server-sent event in the session stream.

One of the following:

Stream Events

require "anthropic"

anthropic = Anthropic::Client.new(api_key: "my-anthropic-api-key")

beta_managed_agents_stream_session_events = anthropic.beta.sessions.events.stream("sesn_011CZkZAtmR3yMPDzynEDxu7")

puts(beta_managed_agents_stream_session_events)

{
  "id": "sevt_011CZkZGOp0iBcp4kaQSihUmy",
  "content": [
    {
      "text": "Where is my order #1234?",
      "type": "text"
    }
  ],
  "type": "user.message",
  "processed_at": "2026-03-15T10:00:00Z"
}

Returns Examples

{
  "id": "sevt_011CZkZGOp0iBcp4kaQSihUmy",
  "content": [
    {
      "text": "Where is my order #1234?",
      "type": "text"
    }
  ],
  "type": "user.message",
  "processed_at": "2026-03-15T10:00:00Z"
}