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strands.vended_tools.subagent.subagent

Subagent tool for delegating a task to a child agent at runtime.

Provides :func:make_subagent (a factory that lets the developer pin safety limits and authority modes). Each call resolves the model’s arguments through the authority-mode system (see :mod:~strands.multiagent.spec), builds a child agent via an :data:AgentBuilder, runs it, and streams the result back.

make_subagent

Section titled “make_subagent”
def make_subagent(*,
                  builder: AgentBuilder | None = None,
                  presets: Mapping[str, Preset] | None = None,
                  default_preset: str | None = None,
                  instructions: Open | Choice | Fixed | None = None,
                  tools: Choice | Fixed | Inherit | None = None,
                  mcp_servers: Choice | Fixed | Inherit | None = None,
                  model: Inherit | Choice | Fixed | None = None,
                  context: Fixed | Choice | None = None,
                  max_depth: int = DEFAULT_SUBAGENT_MAX_DEPTH,
                  name: str = "subagent") -> AgentTool

Defined in: src/strands/vended_tools/subagent/subagent.py:366

Build a subagent tool whose schema is derived from the axis modes and presets.

Each axis accepts a policy from :mod:~strands.multiagent.spec that controls what the model sees and can supply. Omitted axes use sensible defaults.

Raises:

  • ValueError - If max_depth < 1, name is empty, or a Choice axis violates its constraints (empty options, multiple=False for tools).

subagent

Section titled “subagent”

Pre-built subagent tool with default settings (generalist preset, all axes using defaults).