watermark_image

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

With no annotations, the description must disclose behavioral traits. It only states the action but does not mention whether the original image is modified or a new file created, requirements for input, or side effects. Critical information is missing.

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 a single sentence, which is concise but overly brief given the tool's complexity. Important information is omitted, so brevity is not a virtue here.

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 4 parameters, no annotations, and an output schema (whose content is unavailable but the description doesn't mention returns), the description is inadequate. It does not explain the output format, edge cases, or parameter constraints.

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 schema has 4 parameters with 0% description coverage, yet the description adds nothing about parameter meaning beyond their names. For example, 'theme' and 'watermark_text' have defaults but no explanation of valid values or format. The description fails to compensate for the schema's lack of documentation.

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's function: overlaying a brand banner and watermark onto an image. It uses a specific verb ('overlay') and resource ('graphic or photo'), distinguishing it from sibling tools that retrieve assets or palettes.

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 gives no guidance on when to use this tool versus alternatives (e.g., get_brand_asset_paths) or prerequisites such as input image format or permissions. An agent would have no context for appropriate invocation.

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