subagent

type Config struct {
	Provider    llm.Provider
	ParentTools *tool.Registry
	Agents      map[string]Definition
	MaxDepth    int // default 3
	CanUseTool  permission.CanUseTool
	Hooks       harness.HookRunner
	// Transcript, when non-nil, persists each subagent run to its own sidechain
	// file under the parent session (whose id is read from the context). Subagent
	// tokens are recorded there, separate from the parent's totals.
	Transcript *transcript.Store
}

type Definition struct {
	Description    string          // shown to the parent model in the Agent tool prompt
	Prompt         []string        // the subagent's system prompt
	Tools          []string        // tool names it may use (empty = inherit all)
	PermissionMode permission.Mode // its permission mode (default: parent's)
	MaxTurns       int
}