Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already cover readOnly/idempotent, yet the description adds real behavioral context beyond them: the priority ordering of question sources, the fact that NEXUS pre-attempted resolution, the one-at-a-time design constraint, and which tool consumes the result. It even clarifies why merge doubts are excluded.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with the core purpose and the priority ordering immediately after. Slightly padded by the 'Read-only: fetching a question does not change it' sentence, which restates the readOnlyHint annotation and is the one sentence that does not fully earn its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description carries the return-shape burden and does so precisely, describing the nullable pregunta object, its fields, and the pendientes counters. An agent has everything needed to call it and interpret the response.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The tool takes zero parameters, so the baseline is 4; there is nothing for the description to disambiguate on the input side. It does add value by naming the returned fields (texto, datos, respuestas, pendientes), though that is more return-shape than parameter semantics.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb and resource ('Return the next pending question NEXUS has for the user') with an explicit null case. It also names the sibling it is not (get_merge_doubts) and explains the two question sources, so an agent can distinguish it from get_merge_question and get_next_question-adjacent tools without opening a schema.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly states when to use it (one question at a time, after NEXUS has already attempted automatic resolution) and when not to (entity-merge doubts, routed to get_merge_doubts). It also names the follow-on tool, answer_question, for applying answers or postponements.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.