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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description does not need to repeat those. It adds the scope detail that only lists owned by the linked user are returned, which is useful but not extensive behavioral context. It is minimal and does not contradict annotations.

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?

The description is two sentences, front-loaded with the invocation condition and the key constraint. Every word serves a purpose, with no filler or repetition of schema/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?

Given the tool's simplicity (no parameters, output schema present), the description is adequate. It covers the purpose, authentication context, and user ownership. It does not mention pagination or result count, but the output schema likely covers return structure, so this is acceptable.

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?

The tool has zero parameters, so the schema coverage is trivially 100%. Per rubric, 0 parameters gives a baseline of 4. The description does not need to explain parameters and does not attempt to.

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 states 'List their favorite lists' and 'returns only lists owned by the linked user', giving a specific verb and resource with user scoping. This distinguishes it from siblings like delete_property_list or search_properties.

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 explicitly says 'Use this when an authenticated user wants to see their PropFácil favorite lists', providing a clear trigger. However, it does not mention when not to use it or alternative tools, such as get_property_list for a specific list.

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