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

Annotations already declare readOnlyHint=true and idempotentHint=true, so the description does not need to restate these. It adds template syntax and feature options, but does not disclose processing behavior such as asynchronous execution or how the output file is returned. Since output schema exists, this is not a major gap, but it limits the score.

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 long, each serving a clear purpose: stating the action, listing capabilities, and providing a template example. No fluff, and the most critical information appears first.

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?

With 7 parameters, output schema, and annotations present, the description covers the core functionality and template syntax. It could mention whether the operation is asynchronous or returns a job ID (given check_job sibling), but the output schema likely covers return values. Overall, it is sufficiently complete for an agent to use.

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 100%, so the baseline is 3. The description adds value by giving a concrete template example ('Page {n} of {total}') and enumerating supported options that map to parameters (start_at, style, skip_first, etc.), enhancing understanding 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 opens with 'Stamp page numbers or footer text onto every page of a PDF,' which uses a specific verb and resource, clearly distinguishing it from sibling tools like pdf_to_markdown or redact_text. It also skims through main features, reinforcing the tool's purpose.

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 states 'the combination Acrobat cannot do without scripting,' which gives context on when to use this tool. However, it does not explicitly name alternatives or exclusions, so it stops short of a 5.

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