Anthropic API 2026-10-09

You can now let a Claude Managed Agents agent use dynamic workflows, in beta with the `managed-agents-2026-04-01` beta header. For work with many pieces, such as reviewing hundreds of documents, the agent can write a workflow. A workflow is a program that runs many agents in phases and combines their results. The server runs it in the background as a workflow run. To turn dynamic workflows on, set the agent's `multiagent` field to `{"type": "multiagent_20261001", "workflows": {"type": "enabled"}}`. To guide the agent, tell it in its system prompt when to start a run. Follow each run through `workflow_run.*` events on the session's event stream. See Workflow runs.