analyze_ad_video

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

Annotations provide readOnlyHint=true, indicating safe read-only behavior. The description adds behavioral context beyond that: it downloads videos, uses Gemini's video understanding, employs intelligent caching, and provides comprehensive analysis. It doesn't mention rate limits, failure modes, or output format, but with no mutation risk and moderate added context, a 4 is appropriate.

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 brief and front-loaded with 'REQUIRED', immediately conveying importance. It's composed of two sentences with minimal fluff. However, the final phrase 'includes comprehensive video analysis' is somewhat redundant given the previous list of insights, making it slightly less concise than it could be.

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?

The tool analyzes videos from Google, which is a complex task with no output schema and sparse annotations. The description gives a good overview of capabilities and insights but lacks details about input prerequisites (e.g., what form media_url should take) and what exactly the output consists of. It does mention caching and specific analysis dimensions, but misses edge cases and more concrete usage guidance. Overall, it's functional but not fully complete.

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 has 0% description coverage, so the description must compensate by explaining the parameters. It only implicitly suggests that media_url is the video to download, but says nothing about ad_id or brand_name. The meanings of these optional parameters remain unclear, making it difficult for an agent to know what values to provide. This is a significant gap.

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 tool's purpose: analyzing video ads from Google using Gemini. It lists specific extractable insights (visual storytelling, audio, pacing, etc.), which distinguishes it from sibling tools like analyze_ad_image (images vs. videos) and get_google_ads (listing vs. analyzing). The verb 'analyze' and resource 'video ads' are specific and unambiguous.

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 explicitly states it is 'REQUIRED for analyzing video ads from Google', providing clear context for when to use this tool. It doesn't explicitly mention alternatives or when not to use it, but the strong 'REQUIRED' phrasing and the contrast with analyze_ad_image imply the appropriate use case. No exclusions or alternatives are named, so it's slightly below a perfect score.

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