get_video_info

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

No annotations are provided, so the description must carry the burden. It mentions the tool is 'cheap' (1 API unit) and metadata-only, implying read-only behavior. It does not mention error handling, rate limits, or what happens on failure, but for a simple lookup this is acceptable.

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?

Three short sentences with an extra 'Args' section for clarity. No redundant words, every sentence adds value.

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 simple parameters and lack of output schema, the description covers what the tool returns, how to pass parameters, and the cost implication. It could mention the return format, but the purpose is clear enough.

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 0%, but the description adds meaning beyond the schema: video_url can be a full URL or just the video ID, and min_duration_seconds has a default of 600 and is a threshold for an 'excluded_from_analysis' flag. This helps the agent understand usage.

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 it is a 'cheap metadata-only lookup for a single YouTube video' and lists the specific fields returned (title, duration, channel, publish date). It distinguishes itself from sibling tools that perform analysis or batch operations.

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 explicitly tells when to use this tool: to inspect metadata without burning Gemini tokens. It also explains the purpose of min_duration_seconds as a threshold for a flag. However, it does not explicitly mention alternatives or when not to use it, though sibling tools provide context.

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