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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds real context beyond that: the credential requirement, and the rotation behavior where the prior whsec_ still signs for 24 h after POST /api/dono/segredo, producing two v1, parts in the header.

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 purpose and returned fields are front-loaded, which is good, but the bulk of the text is a low-level HMAC-SHA256 recipe (id.timestamp.corpo, 5-minute timestamp tolerance, Standard Webhooks library compatibility) that is tangential to selecting or invoking this tool. That detail is useful but disproportionately long for a zero-parameter read.

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 no output schema, the description responsibly enumerates the return fields (conta/convidado, notification email, franquia, whsec_). It also covers auth and secret rotation. It is nearly complete for a simple read; the signing algorithm is arguably more than needed here.

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?

The tool takes zero parameters, so the baseline is 4. The description correctly implies no input arguments and instead documents the returned fields and the signing secret's format (base64 after the whsec_ prefix), which is the relevant semantic content for a no-arg call.

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 resource and enumerates what it returns: owner state (account or guest), notification email, quota, and the whsec_ webhook-signing secret. An agent can tell this is a read of the owner/account record. It does not, however, distinguish itself from account-adjacent siblings like minha_conta or criar_dono.

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 auth prerequisite is given explicitly ("precisa do token edm_… ou da sessão da conta"), which signals when the call is valid. But there is no explicit when-to-use/when-not, and no routing away from alternatives such as minha_conta or rotacionar_segredo_webhook; the retrieval-for-webhook-verification use case is only implied.

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