Exam 1z0-1157-26 Topic 1 Question 16 Discussion

Input guardrails are checks applied to the initial user input before or alongside execution of the primary agent workflow. Their purpose is to validate whether incoming content satisfies defined security, safety, relevance, or policy requirements and to interrupt execution when an unacceptable condition is detected.
The official OpenAI Agents SDK documentation states that input guardrails receive the same initial input supplied to the agent and can trigger a tripwire that stops execution. Guardrails can therefore be used to detect malicious or otherwise disallowed user requests before they propagate through an expensive or action-capable agent workflow. Blocking execution is particularly important for security-sensitive cases because it can prevent the agent from consuming tokens or executing tools when the input fails validation.
Option B describes output guardrails , which run against the final agent output. Role-based tool authorization is a separate tool-access control problem, while audit logging is normally implemented through observability, tracing, or application-level compliance mechanisms rather than defining the primary input-guardrail function.
Therefore, D is the correct answer and agrees with the supplied course source.
Study Guide reference/topic: OpenAI Responses API and Agents SDK - input guardrails, output guardrails, tripwires, safety validation, and execution blocking.