analyze_ad_video

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

Annotations already declare readOnlyHint and openWorldHint, and the description adds substantial behavioral context: it downloads and processes videos via Gemini, extracts specific narrative elements, notes that TikTok CDN URLs expire quickly, and explains the caching strategy for stability. This goes well beyond the annotations and gives the agent a clear model of what happens during invocation.

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 compact sentences, front-loaded with 'REQUIRED', efficiently convey purpose, extraction details, parameter guidance, and caching. Every sentence adds value with no redundancy or filler.

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 tool with no output schema, the description covers the core functionality, critical parameter usage, processing details, and caching behavior. The only notable gap is the roles of media_url and brand_name, which leaves some cross-parameter scenarios ambiguous. Overall, it is reasonably complete for an agent to invoke successfully.

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 schema has 0% description coverage, and the description compensates for only one of three parameters: ad_id is thoroughly explained with its signed-URL rationale. However, media_url and brand_name are left undefined, and the relationship between ad_id and media_url is not clarified. This partial coverage earns a mid-range score.

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 analyzes TikTok video ads, with a specific verb ('analyzing') and resource ('video ads from TikTok'). It enumerates the specific aspects extracted (hook, scene-by-scene storytelling, on-screen text, audio/voiceover, pacing, brand messaging), which distinguishes it from sibling tools like analyze_ad_image.

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 opening 'REQUIRED for analyzing video ads from TikTok' frames when to use the tool. It also gives a critical usage instruction ('ALWAYS pass ad_id') with a clear rationale. However, it does not explicitly mention when not to use it or name alternatives, though the scope restriction to video ads and the presence of analyze_ad_image imply the boundary.

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