Fetch Pdf

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

With no annotations, the description carries the full behavioral burden and does so well: it names the conversion engine (PyMuPDF 2.x), explains pagination, discloses the routing logic and rate-limit rationale, identifies the `source` value, and states the failure response shape.

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 front-loaded with the core action and conversion detail, then adds routing and failure behavior without unnecessary repetition. Every sentence contributes useful operational context.

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?

An output schema exists, so the description need not fully document return values, and it already covers routing and failure behavior. The main completeness gap is that parameter behavior is left almost entirely to an undocumented schema.

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 0%, and the description does not explain the `url`, `offset`, or `max_chars` parameters. The phrase "Paginated like fetch_page" gives only a weak hint about offset/max_chars and does not compensate for the missing parameter semantics.

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: "Download a PDF and convert it to markdown." It also differentiates the tool from fetch_page by noting pagination behavior and explains the arXiv-specific routing, so an agent can distinguish its role without opening the schema.

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?

It gives clear conditional guidance for arXiv paper PDFs: alphaxiv is the default extracted-text route, and direct download is used only when alphaxiv lacks the paper. However, it does not explicitly say when to choose fetch_pdf over siblings such as fetch_page, fetch_stealth, or alphaxiv_fulltext beyond the PDF conversion context.

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