set-watermark

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

No annotations are provided, so the description carries the burden. It discloses the quota cost and the action of uploading from a local file, but it does not mention whether an existing watermark is replaced, any permission requirements, or side effects. This is a partial disclosure but leaves key behavioral traits unstated.

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 exceptionally concise: two short sentences. The first states the action and resource, and the second provides a cost note. There is no redundant or filler content; every word earns its place.

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 annotations and no output schema, the description is somewhat minimal. It covers the core function and cost but does not explain overwrite behavior, prerequisites (e.g., ownership), or what constitutes successful completion. For a 5-parameter tool with 2 required, this is adequate but not complete.

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 input schema has 100% coverage with all parameters described, so the baseline is 3. The description does not add new parameter-specific meaning beyond what the schema already provides, aside from reinforcing that the file is a local image for 'filePath'. No additional clarity on 'offsetMs', 'position', or 'durationMs' is offered.

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 uploads and sets a channel's video watermark from a local image file. It uses a specific verb ('upload and set') and resource ('channel's video watermark'), distinguishing it from the sibling 'unset-watermark' and other tools.

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 implies this tool is used to set a watermark, especially given the sibling 'unset-watermark' exists, but it does not explicitly state when to use it versus alternatives or any exclusions. The quota cost hint provides some context but not clear when/when-not guidance.

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