get_v1_media_video_download_by_url

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

Annotations already cover readOnly/openWorld/non-destructive, but the description adds valuable beyond-schema context: the return is a file URL plus headers (the file itself is not downloaded), watermark defaults to true, and requests are live and billed per call. This billing and return-format detail is exactly the kind of behavioral insight the annotation set does not provide.

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?

Front-loaded with the core purpose, then scoping rules, then routing alternatives, then cost model. Every sentence adds a distinct piece of information with no waste.

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 2-param read tool with no output schema, this covers the return shape (URL + headers, file not downloaded), parameter default behavior, sibling routing, and per-call billing. Nothing an agent needs to call it correctly is missing.

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 50%. The url parameter is richly documented in the schema itself (accepted forms, 400 behavior), so the description needn't repeat it. The description does add meaning for watermark ('default true' selects the watermarked version), which is not in the schema. Baseline 3 is appropriate given the schema does the heavy lifting on url.

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?

States a specific verb (Get a download link) and resource (TikTok video by URL), and explicitly distinguishes from siblings get_v1_media_video_download_by_id and get_v1_media_music_download_by_url by naming the condition that selects each.

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?

Explicit alternatives: use by_id when you have the video id, music tool for audio only. Clear when/when-not with no inference required.

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