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

The description adds rich behavioral context beyond the readOnlyHint annotation: the returned URL is short-lived (~15 minutes), shared-access means anyone with it can use it, and sharing should be deliberate. It also discloses that multiple matches will be listed for the user to pick, and clarifies that this tool does not send emails. This is exemplary transparency.

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 front-loaded with the core purpose, then systematically covers identification, return value, expiry, scope, and non-email behavior. Every sentence adds relevant information, and the structure makes the tool's behavior easy to parse for an agent.

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 there is no output schema, the description carries the full burden of explaining return values, and it does so explicitly: the signed URL, the document number, and expiration time are all mentioned. It also covers document coverage and disambiguation behavior, making the tool's behavior complete for an agent invoking it.

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?

With 100% schema description coverage, the schema already documents all three parameters clearly. The description reinforces the relationship between docId and docNumber ('give one') but does not add significant new semantics beyond what the schema provides. This meets the baseline but does not exceed it.

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 opens with a specific verb and resource: 'Get a shareable link to the ACTUAL PDF of one invoice, quote or credit note'. It clearly distinguishes the tool from generic document tools by emphasizing the real PDF artifact and explicitly noting it does not email anyone. This makes the purpose unmistakable.

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 when-to-use context: when you need to hand the user or their customer the actual document. It explains the two identification paths (docId from search_documents or printed docNumber) and the disambiguation behavior if multiple matches occur. It stops short of explicitly naming alternative tools for when not to use it, but the guidance is still strong.

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