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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description adds meaningful confirmation: 'Sends nothing.' It also discloses what the preview contains (subject, text, what is missing, whether it would be sent at all), which is substantive behavioral context beyond the annotations.

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?

Two compact sentences, front-loaded with the purpose and output content, then closing with the key non-sending guarantee. No wasted wording.

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?

There is no output schema, but the description explains the returned preview contents: subject, text, missing data, and send status. Combined with annotations covering safety, an agent has enough information to call it correctly for a one-client preview.

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?

Schema coverage is 100%, so the link_id mapping to gestoria_listar_mandantes is already documented. The description adds the important qualifier that the target is 'one accepted client', giving extra meaning about which client is valid beyond the schema text.

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?

The description states a specific preview operation for one client: the exact reminder that would be sent today, including subject, text, missing items, and send eligibility. The phrase 'Sends nothing' clearly distinguishes it from send_reminder and other mutation tools.

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?

It establishes the context ('For a gestoría account', 'one accepted client today') and signals this is a dry-run preview. It does not explicitly name send_reminder as the alternative or state when not to use this tool, so it stops short of full routing guidance.

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