Nous Research has shipped asynchronous subagent delegation for Hermes Agent, its open-source personal agent framework. The update, announced on X by co-founder Teknium on June 15, lets a parent agent spawn background child agents and keep working instead of blocking until delegated tasks finish.

The change addresses a practical bottleneck in multi-agent orchestration. Hermes Agent’s existing delegate_task tool spawns isolated child agents with their own conversations, terminals, and toolsets. Only the final summary returns to the parent, keeping the parent’s context window lean. But until this update, the parent froze inside the tool call until every child completed, according to MarkTechPost’s technical breakdown.

The Async Toolset

The new async_delegation toolset, tracked in GitHub issue #5586, provides six operations covering the full subagent lifecycle:

  • delegate_task_async spawns a background agent and returns a task ID immediately
  • check_task provides non-blocking status and recent output
  • steer_task injects a message into a running task
  • collect_task blocks until a task finishes and returns the full result
  • cancel_task stops a running task
  • list_tasks shows all async tasks in the session

Background agents run as in-process threads, reusing the same credentials, toolsets, and API configuration as synchronous delegation. Subagent isolation remains strict: each child starts with a fresh conversation and has no access to the parent’s history, as MarkTechPost reported.

Practical Implications

The update enables several workflows that synchronous delegation could not support. A parent agent can start a long research task in the background while continuing to draft documents. Multiple subagents can evaluate different approaches in parallel without cross-contamination. A user can steer or cancel a running task mid-flight.

Hermes Agent’s TUI includes an /agents overlay (aliased /tasks) that shows a live tree of running and completed subagents.

The async toolset runs within a single session and is not durable across turns. Cross-turn persistence is planned under a separate proposal (GitHub issue #4949). Existing users can access the update by running hermes update.