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

The annotations already establish a safe, read-only, idempotent operation, while the description adds meaningful scope and result behavior: included list types, excluded Views, membership counts, and pending-suggestion counts. It does not discuss operational details such as pagination, ordering, or freshness, so it is informative rather than exhaustive.

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 compact sentences front-load scope, exclusions, and returned metadata, then finish with actionable selection guidance. No wording merely restates the tool name or repeats the annotations.

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 zero-argument, read-only listing operation with an output schema, the description supplies what an agent needs to select and invoke it: scope, exclusions, useful result fields, and the list_id discovery workflow. Detailed return typing can remain in the output schema, so no additional response-format explanation is necessary.

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 are no input parameters, so the empty schema is already complete and warrants the baseline score. The mention of list_id usefully explains the downstream value of the results, although it is not an input parameter requiring further documentation.

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?

It clearly identifies a listing operation over the user's personal, Team, and shared lists and summarizes the per-list metadata returned. The explicit Views exclusion and list_views pointer distinguish it from a close sibling.

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 entry-point rule—"Start here when the user names a list"—and explains that the practical goal is obtaining list_id. It also provides a concrete alternative by excluding Views and routing those requests to list_views.

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