Claude Platform Docs

Stream Events

BetaManagedAgentsStreamSessionEvents beta().sessions().events().streamStreaming(EventStreamParamsparams = EventStreamParams.none(), RequestOptionsrequestOptions = RequestOptions.none())
GET/v1/sessions/{session_id}/events/stream

Stream Events

Parameters
EventStreamParams params
Optional<String> sessionId
Optional<List<BetaManagedAgentsDeltaType>> eventDeltas

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.

AGENT_MESSAGE("agent.message")
AGENT_THINKING("agent.thinking")
Optional<List<AnthropicBeta>> betas

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

MESSAGE_BATCHES_2024_09_24("message-batches-2024-09-24")
PROMPT_CACHING_2024_07_31("prompt-caching-2024-07-31")
COMPUTER_USE_2024_10_22("computer-use-2024-10-22")
COMPUTER_USE_2025_01_24("computer-use-2025-01-24")
PDFS_2024_09_25("pdfs-2024-09-25")
TOKEN_COUNTING_2024_11_01("token-counting-2024-11-01")
TOKEN_EFFICIENT_TOOLS_2025_02_19("token-efficient-tools-2025-02-19")
OUTPUT_128K_2025_02_19("output-128k-2025-02-19")
FILES_API_2025_04_14("files-api-2025-04-14")
MCP_CLIENT_2025_04_04("mcp-client-2025-04-04")
MCP_CLIENT_2025_11_20("mcp-client-2025-11-20")
DEV_FULL_THINKING_2025_05_14("dev-full-thinking-2025-05-14")
INTERLEAVED_THINKING_2025_05_14("interleaved-thinking-2025-05-14")
CODE_EXECUTION_2025_05_22("code-execution-2025-05-22")
EXTENDED_CACHE_TTL_2025_04_11("extended-cache-ttl-2025-04-11")
CONTEXT_1M_2025_08_07("context-1m-2025-08-07")
CONTEXT_MANAGEMENT_2025_06_27("context-management-2025-06-27")
MODEL_CONTEXT_WINDOW_EXCEEDED_2025_08_26("model-context-window-exceeded-2025-08-26")
SKILLS_2025_10_02("skills-2025-10-02")
FAST_MODE_2026_02_01("fast-mode-2026-02-01")
OUTPUT_300K_2026_03_24("output-300k-2026-03-24")
USER_PROFILES_2026_03_24("user-profiles-2026-03-24")
USER_PROFILES_2026_08_18("user-profiles-2026-08-18")
ADVISOR_TOOL_2026_03_01("advisor-tool-2026-03-01")
MANAGED_AGENTS_2026_04_01("managed-agents-2026-04-01")
CACHE_DIAGNOSIS_2026_04_07("cache-diagnosis-2026-04-07")
DREAMING_2026_04_21("dreaming-2026-04-21")
THINKING_TOKEN_COUNT_2026_05_13("thinking-token-count-2026-05-13")
SERVER_SIDE_FALLBACK_2026_06_01("server-side-fallback-2026-06-01")
SERVER_SIDE_FALLBACK_2026_07_01("server-side-fallback-2026-07-01")
FALLBACK_CREDIT_2026_06_01("fallback-credit-2026-06-01")
FALLBACK_CREDIT_2026_07_01("fallback-credit-2026-07-01")
AGENT_MEMORY_2026_07_22("agent-memory-2026-07-22")
MID_CONVERSATION_TOOL_CHANGES_2026_07_01("mid-conversation-tool-changes-2026-07-01")
COMPACT_2026_01_12("compact-2026-01-12")
COMPUTER_USE_2025_11_24("computer-use-2025-11-24")
MCP_TUNNELS_2026_06_22("mcp-tunnels-2026-06-22")
STRUCTURED_OUTPUTS_2025_11_13("structured-outputs-2025-11-13")
TASK_BUDGETS_2026_03_13("task-budgets-2026-03-13")
THINKING_DISPLAY_UPDATES_2026_08_18("thinking-display-updates-2026-08-18")
CE_USER_MANAGEMENT_2026_07_13("ce-user-management-2026-07-13")
Returns
class BetaManagedAgentsStreamSessionEvents: A class that can be one of several variants.union

Server-sent event in the session stream.

class BetaManagedAgentsStreamSessionEvents: A class that can be one of several variants.union

Server-sent event in the session stream.

Stream Events

package com.anthropic.example;

import com.anthropic.client.AnthropicClient;
import com.anthropic.client.okhttp.AnthropicOkHttpClient;
import com.anthropic.core.http.StreamResponse;
import com.anthropic.models.beta.sessions.events.BetaManagedAgentsStreamSessionEvents;
import com.anthropic.models.beta.sessions.events.EventStreamParams;

public final class Main {
    private Main() {}

    public static void main(String[] args) {
        AnthropicClient client = AnthropicOkHttpClient.fromEnv();

        StreamResponse<BetaManagedAgentsStreamSessionEvents> betaManagedAgentsStreamSessionEvents = client.beta().sessions().events().streamStreaming("sesn_011CZkZAtmR3yMPDzynEDxu7");
    }
}
{
  "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"
}