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

No annotations, so the description carries the burden. It does disclose billing (1 credit per call), which is useful behavioral context not available elsewhere. It omits return format, edge cases (videos with no category), and auth needs.

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?

Very short and front-loaded, but the '**string**' prefix and 'Group: Specific video Info' are formatting noise rather than useful content, detracting from clarity without adding length problems.

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 single-parameter read tool with full schema coverage and no output schema, the core purpose and billing cost are stated. However, without annotations and with no output schema, there is no disclosure of what is returned (a category name? an object?) or edge-case behavior.

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%, and the single 'id' parameter is fully documented with a regex pattern and example. The description adds no parameter meaning beyond the schema, so baseline 3 applies.

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?

States a specific resource (YouTube video category) tied to a video, distinguishing it from siblings like get_info_title or get_info_duration. The 'Group: Specific video Info' phrase is filler, and the '**string**' prefix is a type annotation, not purpose.

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?

No guidance on when to use this versus alternatives. Sibling tools (get_info, get_info_title, etc.) imply a family but the description never says this retrieves one specific field only when a category is needed.

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