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

Annotations only say destructiveHint=true and idempotentHint=false; the description goes well beyond by explaining that sharing mints a new random token and invalidates the previous link, and that the public view exposes name and products at today's prices but never owner, notes or saved prices. It also documents the not_found error for a foreign id, which no annotation conveys.

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 compact clauses, each mapping to a distinct behavior (rename, share/unshare with token rotation, public-view scope, error case). The most consequential detail, link invalidation, is stated inline with the action that causes it.

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 4-param mutation tool with no output schema, it covers side effects, visibility of shared data and the not_found case, which is what an agent most needs. The only gap is the effect of `locale` on the response.

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 75%, and the one undescribed property, the bare `shared` boolean, is fully explained in the description including both true and false semantics. `name` and `list_id` are already covered by the schema; only `locale` is left entirely undocumented.

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 and resource ('Changes one of the signed-in person's lists') and then enumerates the two mutation modes, name and shared. It is trivially distinguishable from delete_list, create_list and add_to_list without opening 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?

The description makes clear this is the tool for renaming and for turning sharing on/off, and the 'shared: false removes the link' phrasing tells the agent this is the unshare path rather than a separate tool. It does not explicitly name an alternative or exclusion, so it stops 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.