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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false. The description adds the concrete effect ('the seller no longer sees it'), which is useful, but omits reversibility, whether the contact is deleted or merely hidden, and what happens on a repeat call (idempotency).

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?

One tight sentence, front-loaded with the actor and action, then the consequence. No filler and nothing repeated from structured fields.

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 single-parameter, no-output-schema tool with annotations covering the safety profile, the description is adequate on the 'what happens' dimension but leaves the parameter unexplained and says nothing about reversibility or repeat-call behavior.

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 0% and the single required parameter (order_id) is never mentioned or explained in the description. The phrase 'on buy' hints at an order context but gives no format, source, or meaning for order_id, so the description does not compensate for the coverage gap.

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 verb+resource (take back the contact), names the actor (Buyer), and ties it to the exact sibling that created the state (share_contact / buy). An agent can distinguish this from the 90+ siblings 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?

Gives a clear usage context: the buyer reverses a contact shared via share_contact on a purchase. It implies the when (after sharing contact on buy) but offers no explicit when-not or alternative tool, so it falls 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.