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

There are no annotations, so the description carries the full behavioral disclosure burden. It only outlines the broad output contents (organized tree and feed URLs) and does not mention whether authentication is required, whether the operation is read-only, or what the response shape will be.

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 a single telegraphic phrase with no filler, and the main content is front-loaded. It is concise, though its terseness contributes to ambiguity in other dimensions.

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-parameter tool with no output schema, the description provides the minimum gist: an organized owner tree plus feed URLs. However, it leaves 'owner' ambiguous and does not define the URL/tree structure, so an agent is only partially equipped to interpret 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?

The input schema has zero parameters, so there are no parameter semantics to document. The description does not need to compensate for schema gaps.

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 name 'get_library' plus the description 'Árvore organizada do dono + URLs de feed' clearly identifies a retrieval operation that returns the owner's organized library tree and feed URLs. The resource is specific and distinct enough from sibling tools like get_channel or list_favorites, though 'owner' is somewhat ambiguous.

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?

No statement explains when to use this tool versus alternatives, and there are no prerequisites or exclusions. The intended use is only weakly implied by the tool name and the terse description.

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