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

Annotations already declare read-only, idempotent, closed-world behavior. The description adds useful return-field context (id, name, parent, creation time with a note about finding the newest), which is valuable because there is no output schema; pagination or ordering behavior is not described.

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 sentences, front-loaded with the core operation and return fields, followed by the usage distinction. No wasted text.

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 simple, zero-parameter list tool with annotations covering safety and no output schema, the description provides enough: what it returns, the primary use case, and the relevant alternative sibling.

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 has nothing to document. The baseline for a 0-parameter tool is 4, and the description does not need to compensate for any missing parameter semantics.

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 a specific verb and resource: List the folders in your Switch library. It also names the fields returned (id, name, parent, creation time), which distinguishes it from siblings like search_my_library or create_folder.

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 clearly says to use this tool to find an existing folder and its id, and explicitly names search_my_library as the alternative for word-based search. It does not explicitly cover when not to use it versus create/delete/rename siblings, but the primary use case and alternative are clear.

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