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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds that the link comes with the message already embedded, but says nothing about the returned format (URL string?), whether it opens a chat directly, or any side effects. Modest added value over 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 short sentences, front-loaded with the core resource and followed by usage contexts. No filler, though the grammar is slightly elliptical and the actual action verb is omitted.

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 one optional parameter, no output schema, and read-only annotations, the description is close to sufficient but leaves open what the tool returns and whether 'mensagem' is required. Adequate minimum, not complete.

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 description coverage is 0%, so some compensation is expected. 'Já com a mensagem' hints that the single parameter is the pre-filled message text, but it never names the 'mensagem' parameter, its 800-character limit, or that it is optional.

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 the resource (a WhatsApp link to Camila, with the message pre-filled), which is specific and distinguishable from sibling tools like montar_link_de_compra. The verb is implicit (the tool produces/returns a link) rather than explicitly stated, so it falls just short of a 5.

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?

Gives concrete usage contexts ('para grupos, eventos, prazos especiais ou dúvidas') that tell the agent when this tool is appropriate. It does not name alternatives or exclusions (e.g., when to use a purchase link or catalog tool instead), so it stops short of 5.

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