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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so the description only needs to add non-annotation context — and it does: the link is one-time (single use), internal-only, and triggers no outbound communication. Minor tension between 'one-time link' and idempotentHint, but it's a subtlety, not a contradiction. Link lifetime/expiry is not stated.

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?

Two compact clauses, front-loaded with the return value and followed immediately by the negative scope. No redundant restatement of the title or schema.

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 one-parameter, non-destructive read with rich annotations and no output schema, nothing essential is missing — the agent knows what it gets back and what it must supply. Only edge details (error behavior, link expiry) are absent, which are minor here.

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 coverage is 100%, so the baseline is 3, but the description adds genuine meaning beyond the schema: quoteId can identify an invoice or a document, not just a quote, and it should come from the quote tools. That resolves the main ambiguity an agent would have about where the ID originates.

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?

Specific verb + resource + scope: "Returns a one-time download link for the PDF of an existing quote, invoice or document." It also explicitly rules out two nearby behaviors (no customer-facing link, nothing sent), which distinguishes it from the sibling quote tools it references.

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?

States the trigger condition clearly (existing quote/invoice/document, identified by quoteId from the quote tools) and explicitly excludes the adjacent use case of sending a link to a customer. It doesn't name a concrete alternative tool for the customer-facing case, so it stops just short of full routing guidance.

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