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

The description adds meaningful behavior beyond the sparse annotations: the input is never modified, ranges are 1-based and open-ended, and the free tier has a 30-page limit. It does not address overwrite safety, but that is already covered in the input schema.

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 with no fluff: it leads with the action, gives a concrete range example, then states safety and limits. Every sentence 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 detailed per-parameter schema descriptions, the tool description plus schema cover required inputs, range syntax, overwrite behavior, output naming, and download links. The main omission is explicit guidance about when to prefer this tool over siblings, but the core calling context is 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?

Schema description coverage is 100%, so the schema already documents all parameters with examples. The description reinforces the range syntax with an expanded example but does not add significant new parameter meaning beyond what the schema provides.

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 states a specific verb and resource: 'write one new PDF per range.' This clearly distinguishes the tool from siblings like pdf_merge or pdf_reorder, and the concrete range example makes the split behavior unambiguous.

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 opening phrase 'Call this tool to write one new PDF per range' gives a clear trigger condition. However, it does not explicitly name alternatives or state when not to use the tool, leaving some inference to the agent regarding the sibling tools.

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