Per the AgentForce Configuration and Control Flow Guide, enforcing deterministic business rules—such as restricting certain actions based on a data condition—requires using context variables with conditional filters. The guide specifies: “Use context variables mapped to relevant Salesforce fields to store state information. Then apply conditional filters to ensure actions execute only when specific conditions (e.g., membership tier) are met.”

This ensures the rule is deterministic, meaning the action cannot trigger if the condition is not satisfied.

Option A (object validation rules) restricts record creation or updates but does not control AgentForce’s action logic. Option B (topic instructions) relies on natural language guidance, which is non-deterministic and can be ignored by the model.

Therefore, Option C—creating a context variable mapped to the membership tier and applying a conditional filter—is the correct, documented approach.

References (AgentForce Documents / Study Guide):

AgentForce Implementation Guide: “Conditional Logic Using Context Variables”

AgentForce Study Guide: “Deterministic Action Control with Filters”

Salesforce Agent Configuration Best Practices