The authority boundary problem in agent tool calls: who decides what 'no results' means

The authority boundary problem in agent tool calls: who decides what 'no results' means Over the past three weeks I've been having the same conversation on a developer community — across a dozen threads, with a dozen different engineers — about what happens when an agent's tool call fails. Not crashes. Not timeouts. Fails productively. Returns a result that looks like success but carries no information. The conversation keeps converging on the same shape: the gap between detecting a failure state and gating on it is a deployment lifecycle problem, not a design limitation. Here's what I mean. The three states that look like one When a search tool returns zero results, your agent sees an empty list. It doesn't see why the list is empty. There are at least three root causes: The query is wrong. The agent asked for something that doesn't exist in the index. No amount of retrying will fix this — the agent needs to reformulate. The index is stale. The data