list_playlists

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

The description adds context beyond the annotations by detailing the return fields (snippet and contentDetails) and pagination via page_token. Since readOnlyHint and openWorldHint are already present, the description enhances transparency, though it doesn't cover all potential edge cases.

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 concise with three sentences, each earning its place: purpose, return details, and usage tip with pagination. It is front-loaded and contains no unnecessary words.

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 complexity (4 parameters, output schema, annotations), the description covers key aspects: return fields, pagination, and linkage to sibling tool. It is complete enough for an agent to use effectively without additional context.

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 100%, so the baseline is 3. The description adds minimal new meaning to the parameters; it mentions using page_token for pagination, which is already in the schema. The return info is about output, not parameter semantics, so no significant improvement.

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 clearly states 'List playlists belonging to a channel or fetch specific playlists by ID,' providing a specific verb and resource. It also distinguishes itself from the sibling tool 'list_playlist_items' by mentioning its purpose, making the tool's purpose unambiguous.

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 description explicitly suggests using 'list_playlist_items' to browse videos inside a playlist, giving a clear alternative for a related task. However, it does not explicitly state when not to use this tool, missing a 'when-not' guideline, which keeps it from a perfect score.

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