get_video_metadata

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

With no annotations available, the description carries the behavioral disclosure burden. It credibly explains that the tool uses a no-auth endpoint, returns only a limited set of metadata, and does not expose upload date or full description. It could also mention error behavior or invalid inputs, but the core behavioral limitations are transparently disclosed.

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 compact and front-loaded with the main purpose. The limitation note is valuable context, and the Args section is minimal and directly useful. Every sentence contributes to correct invocation.

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 single-parameter metadata retrieval tool with a provided output schema, the description covers purpose, input format, expected returned fields, and key limitations. Nothing essential for selecting or invoking the tool is missing.

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?

The input schema provides only a bare string type with 0% description coverage, but the description fully compensates by defining accepted values: 'Full YouTube URL or bare 11-char video ID.' This gives the agent exactly what it needs to construct a valid argument.

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 uses a specific verb ('Fetch') and names the exact resources returned ('title, channel name, and thumbnail'), clearly distinguishing this from the transcript-focused sibling tools. It also names the mechanism ('no-auth oEmbed endpoint'), leaving no ambiguity about what the tool does.

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 clearly implies when to use this tool (when basic YouTube metadata is needed without authentication) and explicitly notes when it is insufficient (when upload date or full description is required, which 'require the official Data API + an API key'). It does not explicitly reference sibling tools, but the field-level exclusions provide solid guidance.

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