watermark_pdf

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

No annotations are provided, so the description must fully disclose behavioral traits. It states the tool applies a watermark but omits critical details such as whether the original PDF is modified or a new copy is created, required permissions, or limitations on file size or supported formats. The lack of transparency increases risk for the agent.

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 two sentences, very concise, and front-loaded with the primary action. It avoids unnecessary words and is easy to parse. It could be slightly more structured (e.g., bullet points for conditional parameters) but remains highly efficient.

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 the tool's complexity (16 parameters, no output schema, no annotations), the description is too minimal. It fails to explain the output or side effects, lacks context for deciding between text and image watermarks, and does not address any potential pitfalls. A more complete description is warranted for such a parameter-rich tool.

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% description coverage, so each parameter already includes semantic meaning. The description adds a small conditional usage note ('For type='text' provide 'text'; for type='image' provide 'watermarkImagePath''), which aligns with the schema. This is adequate but not significantly additive beyond the schema.

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 action ('Apply a text or image watermark') and the target resource ('a PDF'). It specifies both the text and image variants, effectively distinguishing the tool's purpose from sibling tools that perform different PDF operations.

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 hints at conditional parameter usage based on type but does not provide guidance on when to prefer watermark_pdf over siblings like flatten_pdf or compress_pdf. There is no explicit 'when to use' or 'when not to use' guidance, leaving the agent to infer context from the tool name alone.

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