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

Annotations already include destructiveHint=true, indicating the tool may create a new resource. The description adds details on the return format and request structure but does not disclose additional behavioral traits like authentication needs or side effects. It neither contradicts nor significantly extends annotations.

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 concise and front-loaded: first sentence states the core purpose and output, followed by the REST endpoint, format-specific payloads, and return object. Every sentence adds value with no 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?

Given 3 parameters, 100% schema coverage, and no output schema, the description is complete. It explains return values (filename, byteLength, pdfBase64), covers both input types, and provides examples. No output schema is needed thanks to the clear return format.

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 each parameter. The description provides concrete examples (e.g., data structures for html and markdown) that clarify usage beyond the schema, earning a score above baseline 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 explicitly states it generates a brand-new PDF from HTML or Markdown, using a specific verb ('generate') and resource ('PDF'). It also distinguishes from sibling tools like anvil_fill_pdf by emphasizing 'brand-new', ensuring the agent can differentiate.

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 clear context on when to use this tool (generating new PDFs) and gives format-specific instructions. However, it does not explicitly state when not to use it or name alternatives, but the differentiation is implied.

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