Exam AI-103 Topic 1 Question 85 Discussion

The correct intervention point is tool call because the prohibited content must be inspected before Agent1 transmits the MCP request to the external server. Microsoft Foundry defines a tool call as "the action and data the agent proposes to send to a tool." This includes the selected MCP operation and its arguments or payload.
A guardrail configured at this stage evaluates the outbound content immediately before execution. When the Violence risk is detected and the response action is configured as Annotate and block , the tool invocation is not executed, preventing the restricted data from leaving the agent boundary.
The other intervention points operate at different stages. User input scans the original user prompt, but harmful content could subsequently be generated within the tool arguments. Tool response scans information returned by the MCP server, which occurs after the outbound content has already been transmitted. Output scans the final answer delivered to the user and therefore does not control agent-to-tool communication.
This aligns with the AI-103 Study Guide topics Configure safety filters, guardrails, risk detection, and content moderation and Govern agent behavior with oversight modes, constraints, and tool-access controls under responsible AI and agentic systems.