sign_pdf

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

With no annotations, the description must carry the burden; it discloses async 202 polling, saving to disk, and support for page ranges, alignment, size, margins, and opacity. However, it does not explain return values, error behavior, or whether the operation creates a new file or modifies the original in place.

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 three sentences, front-loaded with the primary action, then options, then output behavior. It contains no filler and every sentence contributes meaningful information.

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 18 parameters, no output schema, and no annotations, the description covers the core purpose and output location but omits return value details, async polling specifics, and parameter units. It is adequate for a quick overview but leaves notable gaps for a complex API wrapper.

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 only 44%, and the description adds semantic grouping for page ranges, alignment, size, margins, opacity, and output directory/file name. Yet it does not clarify units (mm vs px), boolean flag effects, or the relationship between paired margin/width/height parameters, so compensation is partial.

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 a specific verb ('Add') and resource ('signature image to a PDF'), and names the underlying PDF4me SignPdf API. This distinguishes it from sibling tools like add_image_stamp_to_pdf or add_text_stamp_to_pdf by focusing specifically on signing with an image.

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 the use case (signing a PDF with an image) and gives input requirements, but it does not explicitly state when to use this tool over alternatives or mention exclusions. There is no when-not or alternative guidance, so usage is only implied.

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