delete_contact

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

With no annotations, the description carries full behavioral disclosure: the action is irreversible ('cannot be undone'), executes immediately on the server, and uses the etag for conflict detection. This is exactly the safety-relevant behavior an agent needs before invoking a delete.

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?

Three sentences with the warning front-loaded, followed by the user-consent gate and a concise prerequisite/rationale. Every sentence earns its place and no information is repeated unnecessarily.

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 2-parameter tool with no annotations and no output schema, this description covers the safety profile, param source, ordering, and concurrency behavior. An agent has everything it needs to call the tool correctly and know what will happen.

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 schema already documents both params with source and purpose. The description reinforces the same workflow but adds little semantic meaning beyond the schema, so the baseline of 3 applies.

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 opens with a specific verb and resource: 'Permanently delete a contact (vCard) from the address book.' It clearly distinguishes this from update_contact and create_contact by emphasizing permanent removal and immediate server-side deletion.

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 gives an explicit usage condition: 'Use only when the user explicitly requests deletion,' which doubles as a when-not guard for a destructive action. It also states the required prerequisite workflow: obtain the vCard URL and etag from list_contacts or addressbook_query before calling.

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