veo_download_video

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

With no annotations provided, the description carries full responsibility for behavioral disclosure. It transparently notes the SDK limitation that downloads placeholder data and that the actual API requires allowlist access. It also lists return fields (file_path, file_size, success), giving the agent a clear picture of expected output. Could add more details about failure cases, but the key caveat is well covered.

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 well-structured with clear sections: main purpose, usage bullets, caveat, and return values. It is slightly verbose because the 'Use this tool to' list partly repeats the opening sentence, but every section adds useful context, and the critical placeholder-data caveat is effectively highlighted.

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 is moderately complex, involving a download operation with a major SDK limitation. The description covers the essential context: when to use it, what it returns, and the placeholder-data restriction. The output schema also helps, reducing the need for the description to explain return values in full. It does not cover error handling or prerequisites like session completion, but the sibling tools and schema infer most of this.

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 description coverage is 100%, so the input schema already documents all three parameters with descriptions. The tool description adds no parameter-specific meaning beyond reinforcing that video_index relates to multiple samples, which is already implied by the schema's 'Index of the video to download' text. The baseline of 3 applies because the schema does the heavy lifting.

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 downloads a generated video from a completed generation session, using the specific verb 'Download' and resource 'video'. It distinguishes from sibling tools by listing specific download-related use cases (downloading after generation, selecting from multiple samples, re-downloading).

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 provides clear context for when to use the tool via a bulleted 'Use this tool to' list, covering common download scenarios. It does not explicitly state when not to use it or point to alternatives, but the sibling tool names (e.g., veo_check_generation) make the intended use evident.

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