pdf_fetch

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint, so the safety profile is covered. The description adds the key behavioral detail of falling back to HTML markdown when the URL is not a PDF, which goes beyond the annotations and clarifies expected behavior.

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 two sentences with no wasted words. It front-loads the primary action and then provides the fallback behavior, making it easy to scan.

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?

The description captures the core functionality and fallback, and the output schema covers return values. While it does not mention limitations like pagination behavior or timeouts, the rich schema and annotations make the description sufficiently complete for a tool of this complexity.

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%, and the parameter descriptions in the schema already explain url, pages, headers, and max_chars. The description itself does not add extra parameter semantics, so it rests at the baseline of 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?

The description clearly states the tool fetches a PDF URL and returns markdown text, with a specific verb ('Fetch'), resource ('PDF URL'), and output ('text content as markdown'). It also distinguishes itself from generic fetch tools by mentioning the PDF conversion and fallback behavior.

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 usage for PDF extraction but does not explicitly state when to use this tool over siblings like smart_fetch or browser_fetch. The fallback to HTML markdown is mentioned, but no exclusions or alternative recommendations are provided.

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