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

The annotations declare readOnlyHint=false, but the description frames the tool as a pure 'Get' retrieval and does not disclose what non-read-only behavior entails. This is a direct inconsistency between the description's implied read-only nature and the annotation.

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 front-loaded sentence with no wasted words. It is appropriately sized for a simple two-parameter retrieval tool.

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?

An output schema exists, so return details need not be explained, and the annotations carry some safety context. However, the description remains thin on usage context and contains no guidance about the non-read-only annotation.

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 both the url and language parameters are already documented with clear descriptions. The description mentions only the URL and adds no meaning beyond what the schema provides, which is adequate given high schema coverage.

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 states a specific verb (Get) and resource (YouTube video or Short details) plus the input selector (by URL). It is clear, though it does not explicitly differentiate this tool from sibling platform-media tools such as tiktok_video or x_tweet beyond the platform name.

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?

It gives no when-to-use or when-not-to-use guidance. There is no mention of alternatives, prerequisites, or exclusions, so the agent must infer that this tool applies only when a YouTube URL is present.

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