Download labels

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

Annotations already declare readOnly, idempotent, non-destructive, so the safety profile is covered. The description adds genuinely useful context beyond that: building takes a few seconds, labels use the account's configured size/format, and refunded or later-printing return labels are excluded. That exclusion rule is information an agent could not infer from annotations.

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 lead sentence delivers the core purpose immediately, followed by two short supporting sentences on mechanics and exclusions. Slight redundancy in restating 'Pirate Ship's Print Labels' and the tool title, but no filler beyond that.

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 properly explains what is returned (a link to a generated file), plus latency and exclusion rules. The remaining gap is the unaddressed empty-required-parameters situation: it never says at least one of batch_id or shipment_ids must be provided, nor how size limits affect behavior.

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 only 50% — shipment_ids has no inline description — so the description carries extra burden. It partially compensates by pairing batch_id with 'every printable label of this batch' and contrasting it against 'chosen shipments', but it does not clarify the either/or exclusivity, the 100-item cap, or what happens when no parameter is supplied.

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 first sentence gives a specific verb (download / build a file) and resource (printable labels), and scopes it to either a batch or chosen shipments. This clearly distinguishes it from sibling tools like get_batch, list_batches, and create_batch, which manage batch metadata rather than produce label files.

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 the selection model (batch_id OR shipment_ids) but never states when to prefer one over the other, nor names any alternative tool for related tasks. Usage is hinted at ('of a batch or of chosen shipments') rather than prescribed.

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