Signing link for the certificate holder

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

Annotations declare readOnlyHint=true and openWorldHint=true, and the description is consistent with that. It adds context beyond the annotations: the operation is 'Free', the output is a link handed to a human who signs in the browser, and the agent pre-signs the challenge so the holder 'only signs with the certificate'. It does not cover link expiry or reuse, so not a 5.

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 tight sentences, front-loaded with the distinctive 'Free' marker and followed immediately by what the link is and who receives it. No filler, though the sentences are dense.

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 still conveys that the return is a shareable link, and it covers the safe-read annotation profile and the post-registration sequencing. It leaves the link's validity window and exact payload unspecified, so not fully complete.

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 baseline is 3. The description earns a bump by explaining the workflow relationship between the three inputs: the agent supplies credential_id and challenge_id and its own signature of the challenge so the certificate holder's browser step is minimized.

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 identifies a specific artifact (a signing link) and its audience (the e-CNPJ/e-CPF holder, owner or accountant). It is readily distinguishable from the sibling verify/check/revocations tools, which audit rather than produce a signing link. It never names a sibling explicitly to route the agent, hence not a 5.

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?

It states clear context: 'Use after a registration' and names the required inputs (credential_id, challenge_id). It does not name an alternative tool or a when-not-to-use condition, so it stops short of a 5.

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