List shipments

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

Annotations already declare readOnly/idempotent/openWorld, so the bar is lower, and the description still adds real behavior: results are ordered newest-first, every label the account bought is included unless filtered, and total/limit/offset define the paging envelope. It doesn't mention limits on result volume or rate constraints, keeping it from a 5.

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?

Content is front-loaded with the resource and default ordering before the table/filter detail. The second block is dense and clause-heavy, but nearly every clause carries information an agent needs to build correct filters.

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 10-parameter read tool with no output schema, the description compensates by enumerating the returned fields and explaining the paging envelope (total/limit/offset). Only minor gaps remain, such as the semantics of the sort enum values, which the schema's defaults largely cover.

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 70% schema coverage the description goes well beyond the schema: it specifies what search actually matches (name, email, tracking number, order id), that dates filter on the label creation day in the caller's timezone with an inclusive end day, that status/tracking_status/carrier/batch accept the display values shown in the table, and how total/limit/offset interact.

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 opening sentence names the resource (labels bought in Pirate Ship) and the exact fields returned — recipient, tracking, cost, status — plus the default ordering, 'newest first'. A second sentence anchors it to the Reports > Shipments table, which tells an agent precisely what dataset this represents, distinguishing it from siblings like export_shipments or get_shipment.

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?

Usage is implied through the table analogy ('works like the table's search box') and the parameter walkthrough, but there is no explicit when-to-use/when-not guidance and no named alternative — an agent is left to infer that export_shipments covers CSV export and get_shipment covers a single label.

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