list_backups

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

With no annotations, the description carries the behavioral burden. It discloses ordering and returned fields, which is useful, but it does not explicitly state that this is a read-only operation, what happens with an empty backup history, or any performance or storage implications. The verb 'List' implies read-only, but that is not made explicit.

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 dense sentence that front-loads the action and resource, then lists ordering and key output fields. Every word contributes information, with no filler or repetition.

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 low complexity (one optional parameter, no output schema), the description gives enough to understand the tool's purpose and expected return content. It does not detail the per-format response shape, but the schema already documents response_format, and the description covers the essential data fields.

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 only parameter, response_format, is fully documented by the schema with enum values and descriptions, providing 100% coverage. The description adds no additional parameter meaning, but the schema already handles the semantics adequately.

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 ('List') and a specific resource ('previous library backups'), and adds concrete output details: path, creation date, size, and the _meta.counts summary. This clearly separates it from backup creation/restoration tools and from playlist-snapshot listing 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 intended use is implied: call this when you need to see existing library backups. However, it gives no explicit guidance about when to prefer this over related tools like list_playlist_snapshots, list_saved_snapshots, or restore_library_snapshot, and it does not state exclusions or workflow context.

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