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

With no annotations provided, the description carries the full burden. It does disclose an important constraint: only public_uid may be used, not the internal numeric ID. However, it does not mention authorization requirements for sensitive details, error behavior, or other side effects, which are relevant given the sensitive parameters in the schema.

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?

The description is a single, clear sentence that is front-loaded with the verb 'Consulta'. It contains no filler and effectively communicates the core purpose without unnecessary detail.

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?

The description captures the essential use case and scope. The output schema and parameter descriptions cover return values and optional parameters, so the description is adequately complemented by structured data. It could mention the sensitive options, but the schema already explains them.

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 100%, so all parameters are already well-documented. The description adds no new semantic detail about parameters; it merely reinforces the id requirement ('somente public_uid'), which is already in the schema.

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 clearly states the action: 'Consulta um registro de contato do tenant atual' (queries a single contact record of the current tenant) with the specific identifier 'usando somente public_uid'. This distinguishes it from sibling 'get' tools (different entities) and 'list_contato' (singular vs. list).

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 description provides clear context for use: to fetch a single contact record by public_uid within the current tenant. It implies this tool is for singular lookups, but it does not explicitly mention alternatives or exclusion criteria (e.g., 'use list_contato for multiple records').

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