You have a GitHub repository that contains an agent named Orchestrator.

The configuration must be changed on the agent that performs the delegation. Orchestrator is responsible for coordinating the workflow, so its allowed subagent list must include Summarizer. Adding the new agent to that list makes it an available delegation target alongside Planner, Implementer, and Reviewer.

An agent’s agents property identifies the custom agents it can invoke as subagents. The tools property serves a different purpose: it identifies available capabilities such as reading files, editing code, or invoking agents. Adding a custom agent’s name to the tools list does not register that agent as a callable subagent. The agent invocation tool must also be available; the scenario already establishes that Orchestrator delegates to other subagents.

Changing Reviewer’s configuration would enable a relationship originating from Reviewer, rather than the requested direct invocation by Orchestrator. A handoff also represents a different interaction pattern from having the orchestrating agent invoke a subagent and receive its result.

Availability does not force execution on every task. Orchestrator’s instructions should indicate when a summary is required and what information it should contain.

Study-guide topics: delegation permissions, orchestrator responsibilities, and specialized subagents. Reference: VS Code—Subagents .

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