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

Annotations already indicate the tool is non-destructive, idempotent, and not read-only. The description adds meaningful behavioral context beyond that: it creates one page per image and preserves the given file order, which explains how the output PDF is structured. It does not mention details like return behavior or side effects beyond creating the PDF, but the annotation profile covers safety.

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, front-loaded sentence that covers the tool's main behavior, input format, output format, and ordering with no wasted words. Every phrase carries meaning and nothing is redundant with the title.

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 tool with five well-documented parameters, an output format stated in the description, and annotations covering idempotency and destructiveness, this description is sufficiently complete. It does not describe the return value, but since the tool produces a PDF and there is no output schema, the key call-time information is already covered by the schema and description.

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 all five parameters are documented with their meanings and defaults. The description reinforces the 'files' ordering and the one-per-page layout but does not add substantial new parameter semantics beyond the schema, making the baseline of 3 appropriate.

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: converting JPG or PNG images into a single PDF, with the explicit behavior of one image per page in input order. This clearly distinguishes the tool from all listed siblings, which operate on existing PDFs rather than creating one from images.

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 clearly implies when to use this tool: when you have one or more JPG/PNG images and need a PDF. It also sets expectations about format support and ordering, giving an agent enough context to select it over PDF-only sibling tools, though it does not explicitly name alternatives or exclusion cases.

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