Update Playlist Item

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

The description adds behavioral context beyond annotations: it specifies the update effect, required parameters, error codes (404, 403), and return format. Annotations indicate readOnlyHint=false, which aligns with the update action. No contradictions.

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 well-structured with sections: main action, Args, Returns, Examples, Errors. It is front-loaded with the purpose. Could be slightly more concise, but the structure aids readability.

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 update tool with no output schema, the description covers purpose, all parameters, error scenarios, and an example. It also describes the return format (Markdown + JSON). This is sufficiently complete for effective use.

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 coverage is 100%, so the description adds minimal value beyond the schema. It restates parameter types and required status, and provides an example, but the schema already documents each parameter with descriptions. Baseline 3 is appropriate.

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 'Update the position or video reference of an existing playlist item.' This specific verb+resource combination distinguishes it from siblings like `youtube_add_video_to_playlist` and `youtube_remove_playlist_item`.

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 mentions all four arguments are required, which gives context but does not explicitly state when to use vs alternatives. It implies usage for updating existing items, but lacks explicit when-not or alternative tools.

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