MCP PDF Reader

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It states what the tool does but doesn't describe how it behaves: there's no information on error handling (e.g., for invalid file paths or non-PDF files), performance characteristics, or what 'etc.' includes in the metadata. For a tool with no annotations, this leaves significant gaps in understanding its operational 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 a single, efficient sentence that front-loads the core purpose. It avoids unnecessary words and directly states the action and target. However, the vague 'etc.' at the end slightly reduces clarity, and it could be more structured by explicitly listing key metadata fields or separating usage 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?

Given the complexity of file operations and the lack of annotations and output schema, the description is incomplete. It doesn't specify what metadata is returned (beyond examples), how errors are handled, or any limitations (e.g., file size or encryption). For a tool that interacts with external files and has no structured output definition, more context is needed to ensure reliable use.

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 input schema has 100% description coverage, with the single parameter 'filePath' clearly documented as 'Absolute path to the PDF file'. The description adds no additional parameter semantics beyond what the schema provides, such as file format requirements or path validation rules. With high schema coverage, the baseline score of 3 is appropriate as the description doesn't compensate but doesn't need to.

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 purpose with a specific verb ('Extract') and resource ('metadata information from a PDF file'), and provides examples of what metadata is extracted ('title, author, creation date, etc.'). However, it doesn't explicitly distinguish this tool from sibling tools like 'read_pdf' or 'search_pdf', which might also involve PDF content processing.

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 provides no guidance on when to use this tool versus alternatives. With sibling tools like 'read_pdf', 'search_pdf', and 'extract_pdf_image', there's no indication of whether this tool is for metadata-only extraction or how it differs from tools that might extract content or images. No prerequisites or exclusions are mentioned.

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