Paper 1 · Question 19

A: Combining all tools into one agent violates the principle of scoped tool access. With too many tools, the agent is more likely to use the wrong tool. Each specialist should have only the 4–5 tools relevant to its role.

B: Each specialist gets its own AgentDefinition with its tools restricted to the 4–5 tools relevant to its role. The coordinator has the Task tool (renamed to Agent in current Claude Code v2.1.63; 'Task' still works as a backward-compatible alias) in its allowedTools so it can spawn specialists. This enforces separation of concerns and scoped tool access.

C: Using HTTP calls instead of the Task tool bypasses the Agent SDK's built-in orchestration capabilities. The Task tool is the designed mechanism for subagent invocation and provides proper context management.

D: A single agent with all tools has a higher error rate due to tool selection confusion. Specialist subagents with scoped tools produce more reliable results. As a rough guide, aim for a small set of around 4–5 tools per agent.