aaddyy_pdf_merge

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

With no annotations, the description must carry the behavioral burden. It usefully adds constraints (2–10 files, 20MB each), which an agent cannot derive elsewhere, but omits return format, output handling, and any auth/permission context.

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?

Two tight sentences, front-loaded with the action and followed by constraints. No filler or repetition.

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 single-param utility with no annotations and no output schema, the count and size limits are valuable, but the missing input-format guidance leaves a real gap an agent needs in order to call it correctly.

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?

One parameter with 0% schema description coverage, so the description must compensate. It clarifies that multiple PDFs are expected and gives count/size limits, but never explains the input format — the schema oddly types 'pdfs' as a string, leaving the agent unsure whether to pass a list, comma-separated names, or URLs.

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+resource ('merge PDF files into a single downloadable PDF'), so the purpose is unmistakable. It does not differentiate from the nearest sibling, aaddyy_image_to_pdf, or note how it differs from other document generators in the set.

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 its use via 'Upload multiple PDF files', but gives no explicit when-to-use, when-not-to-use, or alternative (e.g. aaddyy_image_to_pdf). No prerequisites or routing guidance for the agent.

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