PDF.co MCP Server

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

With no annotations provided, the description carries full burden for behavioral disclosure. It states what the tool does but doesn't mention authentication requirements (though api_key parameter hints at it), rate limits, error conditions, or output behavior. The description lacks crucial operational context like whether this is synchronous/asynchronous or how results are returned.

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 appropriately concise with two sentences: one stating the core functionality with specific format examples, and one providing a reference link. The format list could be more efficiently presented, but overall it's front-loaded with essential information without unnecessary verbiage.

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 tool with 7 parameters, no annotations, and no output schema, the description is insufficient. It doesn't explain what happens after conversion (how PDF is returned/stored), error handling, or operational constraints. The reference link partially compensates but doesn't substitute for a self-contained description that enables proper tool selection and invocation.

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%, so the schema already documents all 7 parameters thoroughly. The description adds no parameter-specific information beyond what's in the schema. It mentions supported formats but doesn't clarify parameter implications or relationships. Baseline 3 is appropriate when schema does the heavy lifting.

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: converting various document types to PDF. It specifies the verb 'convert' and lists 12 supported formats, making the scope explicit. However, it doesn't differentiate from sibling tools like 'csv_to_pdf', 'html_to_pdf', or 'image_to_pdf', which perform similar conversions for specific formats.

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 multiple sibling tools for specific format conversions (e.g., csv_to_pdf, html_to_pdf), there's no indication whether this is a general-purpose converter or when specialized tools might be preferred. The reference link is technical documentation, not usage guidance.

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