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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states that an email with a login code is sent, but omits side effects such as rate limiting, code expiration, whether an existing session is invalidated, or whether an email is only sent if the account exists. These are material behaviors for an auth-related mutation.

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 with no filler or redundant wording. It is front-loaded with the core action and reads naturally in Portuguese.

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?

Although the tool is simple with one well-documented parameter, the lack of annotations and output schema means the description is the only behavioral source. It does not explain the auth flow, consequences of calling it, error conditions, or what the agent should do after sending the code. This leaves important operational context 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 100%, so the schema already fully documents the single 'email' parameter. The description mentions 'por e-mail' but adds no semantic detail beyond what the schema states. Baseline 3 is appropriate because the structured field carries the meaning.

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 a specific verb ('Manda' = sends), a resource ('código de login'), and the delivery channel ('por e-mail'). It distinguishes the tool from the sibling auth_verify, which presumably verifies the code rather than sending it. However, it does not explicitly frame this as the start of an authentication flow.

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 gives no guidance on when to use this tool versus auth_verify or any other sibling. It does not mention prerequisites (e.g., unauthenticated user), expected context, or next steps. Usage must be inferred entirely from the name and the description.

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