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

The description says the tool 'Registra' a webhook, implying a non-destructive creation operation, yet the annotation has destructiveHint=true. This is a direct contradiction: registering a webhook does not normally destroy data, and the description adds no mention of overwriting or other destructive effects. The HMAC-SHA256 detail cannot reconcile this mismatch.

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 two sentences, front-loaded with the primary action, and includes a relevant security detail without repetition of schema information. Every word earns its place.

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 tool is simple and the schema covers parameters, but the description omits expected success/error behavior and fails to explain the destructiveHint annotation. While the HMAC note adds value, the unresolved contradiction leaves the description incomplete for robust agent decision-making.

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 baseline is 3. The description mentions event examples already present in the schema's enum and adds no extra meaning about URL format, empresaId, or array structure. The HMAC note is behavioral, not parameter-specific.

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 leads with 'Registra uma URL de webhook' (registers a webhook URL), a specific verb and resource, and clarifies the purpose: receiving real-time company event notifications. This clearly distinguishes it from siblings like 'listar_webhooks' and 'cancelar_webhook'.

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 states the context for use — 'para receber notificações em tempo real de eventos da empresa' — and gives concrete event examples. It provides clear context without explicitly excluding alternatives, which is acceptable given the obvious differentiation from sibling tools.

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