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

Annotations already declare readOnlyHint and idempotentHint, so the description adds value by specifying exactly which structural facts are reported (encryption, outlines, embedded files, JavaScript, etc.) and explicitly stating that text and field values are not extracted. This goes beyond the annotations, though it doesn't describe side effects or error 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 somewhat redundant, repeating the list of structural facts in two sentences, and starts with an unexplained 'Free.' which appears to be a typo or leftover fragment. It could be tightened to a single concise sentence without losing information.

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 presence of an output schema, the description need not detail return values. It covers the tool's purpose, the scope of reported facts, and explicitly excludes text and field values. It lacks usage guidance and has the confusing 'Free.' prefix, but overall it's adequate for a simple read-only inspection 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 has only one parameter (artifact_id) with 0% description coverage, so the description must clarify its meaning. It does by stating 'Structural facts about artifact_id', indicating artifact_id identifies the PDF to inspect. However, it doesn't specify the format or origin of artifact_id, but it's sufficient for a single-param tool.

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 states a specific action (report/inspect) on a specific resource (PDF structure) and enumerates exact facts (page count, sizes, rotations, encryption, form fields, annotations, etc.). It explicitly excludes text and field values, which differentiates it from content-extraction tools like read_form or fill_form, even without naming them.

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 structural inspection but does not explicitly state when to use this tool over alternatives. It notes what it does not do (no text, no field values), giving some guidance, but lacks explicit exclusions or alternative tool names, leaving the agent to infer the appropriate context.

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