download_video

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

No annotations are provided, so the description carries the full burden. It discloses that the tool returns a download URL and implies no destructive side effects, but does not specify URL expiration, authentication requirements, or whether it can be called multiple times. For a simple retrieval tool, this is adequate but not comprehensive.

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?

Two concise sentences: first states the primary action, second provides a critical usage hint. No filler 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 no output schema, the description explains the return value is a 'download URL' but lacks details like format, expiration, or access restrictions. However, for a simple download tool within a video creation context, this is likely sufficient for an agent to use correctly.

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 covers 100% of parameters with descriptions. The tool description adds value by clarifying that 'service' expects values 'heygen' or 'veo' and that 'job_id' should come from a completed video, supplementing the schema's generic descriptions.

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 clearly states 'Get the download URL for a completed video', specifying the verb ('Get') and resource ('download URL'). It distinguishes from sibling tools like creation and status checking by focusing on the download action.

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 instructs to call get_video_status first to ensure completion, providing a clear prerequisite. However, it does not mention when not to use this tool or offer alternatives, which is acceptable for a straightforward retrieval tool.

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