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

Annotations already declare non-destructive, idempotent, and closed-world, so the safety profile is covered. The description adds only 'one library item' as a scope hint, and says nothing about whether names must be unique, what happens on collision, or the effect on share links or existing references.

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?

A single clean sentence with no filler, but it is under-specified rather than concise — the length is driven by omission, not efficiency.

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?

A mutation tool with no output schema, undocumented parameters, and no error/validation guidance. The description does far too little for an agent to call it correctly beyond the trivial case.

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?

Schema description coverage is 0%, so the description must carry parameter meaning. It only hints that 'name' is a display name rather than a filename; the required mediaId UUID parameter and the 1-120 character constraint are left entirely to the raw schema.

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?

Specific verb+resource: 'changes the display name of one library item'. Clearly separable from rename_folder and move_media by its single-item scope, though it never names those siblings.

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 indication of when to use this versus rename_folder, move_media, or edit_video, and no prerequisites (ownership, permissions, whether the item must not be trashed). The agent must infer selection from the name alone.

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