Add Video to Playlist

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

Annotations indicate this is a non-read-only and non-idempotent operation, which the description does not contradict. The description adds value by specifying the OAuth authentication requirement, which is not covered by annotations. However, it lacks details on behavioral aspects like error handling, rate limits, or side effects beyond authentication.

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, efficient sentence that front-loads the core purpose and includes essential authentication information. There is no wasted verbiage, and every word contributes to understanding the tool's function and requirements.

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 tool's moderate complexity (mutation with authentication) and lack of an output schema, the description is minimally adequate. It covers the basic purpose and authentication need but omits details on return values, error conditions, or interaction with sibling tools, leaving gaps in contextual understanding.

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%, meaning all parameters are documented in the schema. The description does not add any semantic details beyond what the schema provides, such as explaining the implications of the 'position' parameter or format requirements for IDs. Baseline score of 3 is appropriate as the schema handles parameter documentation 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 clearly states the action ('Add a video') and resource ('to a YouTube playlist'), which is specific and unambiguous. However, it does not explicitly differentiate from its sibling 'playlists_addVideos' (which likely adds multiple videos), leaving some room for improvement in sibling distinction.

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 that OAuth authentication is required, which provides some context for usage prerequisites. However, it offers no guidance on when to use this tool versus alternatives like 'playlists_addVideos' or 'playlists_create', nor does it specify any exclusions or scenarios where this tool is preferred.

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