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

Goes well beyond the existing destructiveHint=true annotation: it discloses the consequences (loss of owner's balance and utilities), the recovery path (next paid top-up creates a new owner), the signature requirement, the 7-day / only-agent exception for keyless passports, and the exact failure response signature_required.

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?

Four sentences, front-loaded with the action and its consequence, then the gates. Dense and mostly waste-free, though the signature/exception sentence is packed tightly enough to require careful reading.

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?

For a destructive, non-idempotent, zero-required-parameter tool with no output schema, the description covers consequences, preconditions, exceptions, and the specific error an agent should expect. Nothing essential for correct invocation is 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 coverage is 100%, so baseline is 3, but the description earns extra credit by explaining why confirm is needed (last passport of an owner with money) and by contextualizing passport_token as an alternative to a header signature when there is no app sign-in.

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?

"Detach your passport from its owner" gives a specific verb and resource and immediately frames the passport/owner relationship. It does not explicitly differentiate itself from siblings like remove_passport or revoke_passport, so an agent may need to infer which of the three detach-style tools applies.

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?

Provides a concrete triggering scenario ("when whoami shows that a stranger paid your top-up") and states hard preconditions: confirm: true for the last passport of a funded owner, and a passport-key signature. It does not name an alternative sibling tool when leaving is not appropriate, which is the only gap.

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