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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered. The description adds non-obvious behavioral context the annotations cannot: the link grants view access to family/friends and supports quiet claiming in which the owner never sees who claims what — a meaningful privacy property. It omits link lifetime, revocation, and permission requirements.

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 sentences, both earning their place: the first states scope and the anonymous-claim behavior, the second handles the group-list exception. Front-loaded and free of filler, though the second sentence is slightly elliptical ("shared with the group instead" leaves the alternative tool unnamed).

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 read tool with no output schema, the description covers what the operation yields (a share link) and its key behavioral twist. The one real gap is return details — URL format and whether the link expires or can be revoked — which matter for an agent orchestrating sharing.

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?

There is one required parameter at 0% schema description coverage, so the description must carry the meaning. It partially compensates by implying wishlist_id refers to a personal (not group) wishlist, but never states ownership requirements, UUID constraints, or what happens when a group wishlist ID is passed.

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 names a specific verb and resource ("Gets the link") and immediately scopes it to "one of the signed-in person's personal wishlists," which separates it from get_group_invite_link and the group-wishlist siblings without the agent needing to open a 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 carries an implicit when-not clause: group lists "are shared with the group instead," so the agent knows this tool applies only to personal wishlists. It stops short of naming the sibling to use for group lists, so the agent must infer the redirect from names alone.

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