download_paper

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

No annotations are provided, so the description must carry the full burden. It discloses that the tool saves to an output directory and returns download result info, but it does not mention potential issues such as access restrictions, network requirements, file overwrite behavior, or failure handling. This is insufficient for a file-downloading tool.

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 concise and front-loaded with the core purpose. It includes parameter and return documentation without any fluff or repetition. Every sentence contributes useful information.

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 tool with two parameters and no output schema, the description covers the purpose, parameters, and return value. It lacks explicit error-handling or edge-case context, but given the tool's simplicity, it is reasonably 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?

The description explicitly explains both parameters: doi is the paper's DOI identifier, and output_dir is the optional PDF output directory. This adds meaningful context beyond the schema, which only provides titles and defaults. The schema description coverage is 0%, but the description fully compensates.

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 clearly states the tool's action: download a paper's PDF based on DOI. It uses a specific verb (download) and resource (paper PDF), and distinguishes itself from the sibling tool search_papers by focusing on downloading rather than searching.

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 the tool is used when you have a DOI and want the PDF, but it does not explicitly mention when to use it versus alternatives, nor does it provide any exclusions or prerequisites. There is no comparison with the sibling tool search_papers.

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