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

No annotations are provided, so the description carries the burden. It does disclose the return format (base64 of the extracted PDF), which is useful, but it does not describe error behavior (invalid ranges, out-of-bounds pages) or whether the original is preserved.

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 short sentences with zero waste; the action is front-loaded and the return value follows immediately.

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 simple two-parameter tool with fully documented schema and a stated base64 return, the description is largely complete. The main missing piece is error/edge-case behavior, but nothing critical blocks correct invocation.

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 both parameters (file, pages) are fully documented in the schema including the '1-3,5' format and default. The description adds no parameter detail beyond the schema, which is appropriate given full coverage — baseline 3.

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 ('Extract') and resource ('selected pages from a PDF') with clear output ('base64 of the extracted PDF'). It does not explicitly contrast with siblings like pdf_merge or pdf_info, so 4 rather than 5.

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?

Usage is implied by 'Extract selected pages' and the pages parameter, but there is no explicit when-to-use versus alternatives (e.g., pdf_merge for combining, pdf_info for metadata) and no exclusions or prerequisites.

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