Get Invoice Pdf

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

Annotations already declare readOnly/idempotent/non-destructive, but the description adds material context beyond them: the PDF arrives as an embedded resource, the accompanying fields (filename, sizeBytes, downloadUrl), and crucially that downloadUrl is unauthenticated and expires in 15 minutes. The warning against re-emitting bytes is a genuine behavioral disclosure.

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?

Front-loaded with the core purpose, then layered with return-shape and expiry facts – all of which earn their place for a tool whose output has no schema. It runs slightly long with three dense clauses in one sentence, but nothing is filler.

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?

With no output schema, the description carries the full burden of the return contract and does so: embedded resource, field names, unauthenticated 15-minute link, and expiry field. An agent has everything needed to retrieve and hand off the file correctly.

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 single parameter has 100% schema description coverage, and the schema already states it is an 'Invoice (order) ID from `list_invoices`.' The description adds no parameter-level syntax or format detail, so the baseline 3 applies.

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?

States a specific verb+resource (get an invoice PDF) and anchors it to a concrete user-facing equivalent ('the same document as Download PDF on porkbun.com'), which removes ambiguity about what artifact is produced. It also differentiates from the sibling get_invoice by noting that tool only returns a link.

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?

Explicitly routes the agent: use this when you need the file, hand the user `downloadUrl`, and use `get_invoice` 'if you only need the link.' It also gives a direct instruction on what NOT to do (do not reproduce the file's bytes yourself), which is exactly the kind of when/when-not guidance that helps selection and invocation.

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