Instrument multi-agent systems

In a multi-agent system, a parent agent delegates work to child agents. Create child agents from the parent with the AI SDK and Agent Analytics records the delegation: child agents carry [Agent] Parent Agent ID, sessions record the root agent and chain depth, and provider wrappers suppress spurious user-message events inside delegated calls. The AI SDK sets [Agent] Message Source to agent on a delegated user message unless you set the source yourself. Every agent's events stay under one [Agent] Session ID.

Give every agent a stable, human-readable ID. Those IDs become the primary dimension for comparing quality and cost across your system.

Declare and dispatch child agents

Declare children off the parent with .child(), then dispatch to them with runAs() (Node) or arun_as() (Python):

const orchestrator = ai.agent('shopping-agent', { description: 'Orchestrates shopping requests' });
const recipeAgent = orchestrator.child('recipe-agent', { description: 'Finds recipes' });

await orchestrator.session({ userId }).run(async (s) => {
  s.trackUserMessage(userInput);
  const result = await s.runAs(recipeAgent, async (cs) => {
    cs.trackUserMessage(delegatedQuery);
    return openai.chat.completions.create({ model: 'gpt-4o', messages: [...] });
  });
});

For the full delegation semantics (context inheritance, span wrapping, nested children, fan-out), refer to Multi-agent architectures in the SDK reference.

Analyze multi-agent sessions

Each [Agent] Session Record carries [Agent] Root Agent Name and [Agent] Agent Chain Depth. Depth is the number of agents on the longest delegation path: 1 is a single agent, 2 is one hop, and 3 or more is deeper nesting. When a parent fans out to several children, depth follows the deepest branch. Filter Session Records where chain depth is greater than 1 to find multi-agent sessions. Depth 2 means exactly one hop. Group any chart by [Agent] Agent ID to compare agents. Refer to Data hierarchy.

A span's parent span isn't the parent agent. On OpenTelemetry, set the span attribute amplitude.parent.agent.id. Across processes, propagate x-amplitude-parent-agent-id next to the existing agent-id header. A LangSmith forwarder stamps one configured agent: nested LangSmith runs stay tool calls or spans and don't become child agents.