Delete Contact

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

The annotations already declare destructiveHint=true and idempotentHint=false, so the safety profile is known; the description earns credit for adding that address books have no trash or undo and that an unknown contactId errors while deleting nothing. The error-deletes-nothing behavior is consistent with the non-idempotent hint. A small gap remains: it does not say what a successful response returns (though no output schema exists).

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 short sentences, front-loaded with the permanent/no-undo warning, then the id sourcing and alternatives. Nothing is wasted.

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 one-parameter destructive tool with full schema coverage and annotations, the description covers irreversibility, id provenance, pre-check, and the alternative tool. No output schema exists, so nothing further is required.

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% and the single parameter already documents itself as the contact UID from searchContacts, so the description mostly restates provenance. That repeated pointer is useful for sequencing but adds little semantic depth beyond the schema.

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?

"Permanently delete one contact" gives a specific verb, resource, and scope (one contact, permanent), which separates it from updateContact and the bulk deleteMessages-style siblings. An agent can pick it without opening the schema.

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 explicitly names the source of the id (searchContacts), the verification step (getContact first), and the alternative for modification (updateContact). When-to-use and when-not-to-use are both covered.

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