sapiens_stock_video

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

Annotations already declare readOnlyHint and openWorldHint, and the description adds meaningful behavior beyond that: 'Leitura pública, sem auth', downloadable/free/internal status, and the exact return shape for list ({count, items} with fields). No contradiction with annotations.

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?

Dense but well structured: concept first, then auth, sub-actions, and usage guidance. Every clause carries operational value and there is no 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?

The tool has 3 actions, 9 parameters, and no output schema, yet the description covers all actions, the list return shape, filters, and concrete use cases. An agent has enough information to invoke it correctly without opening the schema.

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 baseline is 3. The description adds actionable semantics for key parameters: orientation maps to 9:16/16:9/1:1 and loopOnly maps to clean looping backgrounds for pages. Less central filters like mood, categoryId, and durationMax are left mostly to the schema, so a 4 is appropriate.

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?

Description opens by naming the resource ('Banco de clipe/B-roll stock') and the operation ('catálogo de vídeo curto pronto no CDN, baixável'), and enumerates the three sub-actions. It differentiates from sibling sapiens_video by positioning this as the ready-made B-roll source rather than a generator.

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?

Explicitly states when to use: 'Use pra puxar B-roll pronto em vez de gerar via sapiens_video' and lists concrete integration contexts (page background, ffmpeg B-roll, opening/closing frames). Also gives selection criteria such as orientation and loopOnly that help the agent choose the right clips.

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