Option D allows orchestration effort to scale with the actual request. A simple factual query may require only the web-search agent and a direct coordinator response, whereas a comparative investigation may require web research, document analysis, synthesis, and report generation. Anthropic’s Building Effective AI Agents describes the orchestrator-workers pattern as a central model dynamically identifying subtasks, delegating them, and combining the results. It is specifically appropriate when the required subtasks cannot be predicted reliably in advance. Anthropic’s multi-agent research architecture likewise emphasizes varying the number of agents and tool calls according to task complexity. Option A introduces an inflexible binary decision and still sends every non-factual request through the full pipeline. Option B requires labeled data, ongoing retraining, and reliable definitions of the “optimal” agent combination. Option C is easier to implement but will become brittle as new query types appear. A capable coordinator can examine the requested output, necessary evidence, source requirements, and analytical depth at runtime, then invoke only the specialists that materially contribute to the answer.

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