youtube-mcp

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It adds value by mentioning 'Costs 100 quota units (uses search.list)', which informs about resource usage and underlying API method, but it doesn't cover other aspects like rate limits, authentication needs, or what happens on errors. This partial disclosure is adequate but not comprehensive.

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 appropriately sized and front-loaded with the core purpose in the first sentence, followed by parameter details. Every sentence adds value, with no wasted words, though the structure could be slightly improved by grouping related information more explicitly.

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 (3 parameters, no nested objects), no annotations, and the presence of an output schema (which handles return values), the description is reasonably complete. It covers purpose, cost, and parameters, but lacks usage guidelines and some behavioral details like error handling, making it good but not perfect.

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 compensate. It adds meaning by explaining each parameter: 'channel_id' is identified as 'The channel ID', 'max_results' specifies range and default, and 'order' lists possible values. This provides clear semantics beyond the bare schema, though it could be more detailed (e.g., explaining 'relevance' context).

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 verb 'List' and resource 'videos on a channel', making the purpose specific and understandable. However, it doesn't explicitly differentiate from sibling tools like 'list_playlist_items' or 'search_videos', which might also retrieve videos in different contexts, so it doesn't reach the highest score.

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 provides no guidance on when to use this tool versus alternatives like 'search_videos' or 'list_playlist_items', nor does it mention prerequisites such as needing a valid channel ID. It only lists parameters without contextual usage advice, leaving the agent to infer when this tool is appropriate.

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