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

With no annotations present, the description carries the full behavioral burden. It does disclose one genuinely non-obvious trait — the author is derived from the MCP key rather than a parameter — but leaves mutation semantics undescribed: no statement on immutability/append-only nature, visibility to other users, or failure behavior when the target ids are ambiguous or absent.

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 with the target selection stated first and the author behavior second; no filler. Density is appropriate for a create tool.

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?

For a simple three-parameter create with no output schema, the description covers the main purpose and the author-derived field, which is the minimum an agent needs to attempt a call. The exclusivity and validation rules that would make the call reliably correct are still missing.

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 the description must compensate. It explains what contato_id and oportunidade_id identify, but adds no constraint details (mutual exclusivity rules, whether the id must exist, whether conteudo is the note body) and says nothing about the required conteudo parameter beyond the verb 'registra'.

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 ('Registra uma nota') and names both attachment targets (contato_id / oportunidade_id), which is enough for an agent to distinguish it from the tarefa_create sibling. It stops short of an explicit contrast with any sibling tool.

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?

The capitalized 'OU' implies the note attaches to exactly one of the two entities, which is useful routing guidance. However, it never says what happens if both ids are supplied, if neither is supplied, or whether an alternative tool should be used in those cases.

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