Extract from PDF

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

Annotations already declare readOnlyHint and openWorldHint, and the description adds substantial behavioral context: server-side retrieval via the fetch-url ladder, support for paywalled/bot-protected PDFs, and in-process text extraction without external converters. This enriches the annotations with actionable operational details.

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 that are front-loaded with the core action and each sentence provides distinct value: purpose and input types, retrieval/behavior details, and pairing recommendation. There is no filler or redundancy.

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 extraction tool with no output schema, the description covers input source types, retrieval mechanism, return value, and a follow-up tool suggestion. It is sufficiently complete for an AI agent to know what to expect and how to use the tool.

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 schema provides 100% coverage for both parameters, so the baseline is 3. The description adds meaning by explaining that URLs are retrieved server-side via a special ladder and that protected PDFs work, which goes beyond the schema's simple mention of 'retrieved server-side first' for 'source'. It does not discuss 'max_pages', but the schema fully covers it.

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 a specific verb-resource pair ('Extract text from a PDF') and clarifies the intended use case ('for appraisal or data extraction'). It differentiates from sibling tools like fetch-url by emphasizing PDF-specific extraction and mentions the in-process return behavior, making its purpose unmistakable.

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 states when to use the tool ('for appraisal or data extraction') and suggests pairing with appraise-evidence, providing clear contextual guidance. However, it does not explicitly state when not to use it or name alternative tools like fetch-url for non-PDF sources, so it lacks full exclusion guidance.

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