pdf_verify_signature

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

No annotations are provided, so the description carries the burden. It discloses the key behavioral limitation (no CA trust-chain validation) and the cost ($0.01), which is useful. It does not mention whether the tool requires network access or what happens with unsigned PDFs, but the core behavior is transparent.

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 compact and front-loaded: it states the action, the input, the outputs, the limitation, and the cost in two sentences. Every clause earns its place.

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 single-parameter tool with no output schema, the description covers the essential context: what it checks, what it returns conceptually, and its limitation. It could mention whether the tool verifies against a trusted timestamp or handles multiple signatures, but these are not critical for basic 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 0%, so the description must compensate. It explains the file parameter is a local path ('local path') and that it operates on a PDF, but it does not specify accepted file extensions, path formats, or error conditions. The description adds some meaning beyond the bare schema but not enough to fully compensate.

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 checks digital signatures of a PDF, specifying what it reports (who signed, when, whether unchanged) and explicitly notes it does not do CA trust-chain validation. This distinguishes it from sibling PDF tools like pdf_protect, pdf_unlock, and pdf_compare.

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 when to use it: to verify a PDF's signature integrity without needing full CA validation. It does not explicitly name alternatives or state when not to use it, but the scope is clear enough for an agent to select it among many PDF tools.

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