Start with deterministic rules
If a request can be routed by a reliable condition, use that condition. Simple rules are easier to test, explain and operate. Adding a language model introduces uncertainty and an ongoing evaluation obligation.
Define the judgement boundary
An agent may help interpret an unstructured enquiry, retrieve relevant knowledge and draft a response. Define which sources it can use, which tools it can call and which actions require approval. Never treat fluent output as verification.
Evaluate before expanding
Test representative examples, ambiguous inputs and failure cases. Measure usefulness and error patterns. Log actions appropriately, respect access controls and provide recovery paths. Expand permissions only when evidence supports it.