list_root_folders

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

With no annotations, the description carries the full burden, and it explains what the response contains (root folders, free space, unmapped folders) rather than just restating the endpoint. It does not explicitly state side-effect safety, but the verb 'list' and the absence of any mutation language make the read-only behavior clear enough.

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 carry all the needed information with no filler. The return-content detail is front-loaded, and the downstream purpose is provided in a single follow-up sentence.

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 no parameters and no output schema, the description is complete enough to invoke the tool correctly and know what to expect. The only minor omission is an explicit pointer to get_root_folder for single-folder lookups, but this is not essential for this simple list operation.

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 takes zero parameters, so there is nothing the description needs to explain about parameter values; the baseline of 4 applies. The description accurately focuses on the output rather than input.

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 uses a specific verb and object ('List root folders') and adds concrete scoping details: it returns free space and any unmapped folders in each root folder. This makes it easy to distinguish from the sibling get_root_folder (single resource) and from media-management tools.

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 second sentence gives a clear when-to-use signal: add_series needs one of these paths, so this is the tool to call before adding a series. It does not explicitly name the alternative get_root_folder for fetching a single folder, but the plural list semantics imply the broader use case.

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